CB/T 3254.1-1994 Marine diesel engine bench test standard Environmental conditions and power fuel consumption and oil consumption verification CB/T3254.1-1994 standard download decompression password: www.bzxz.net

Shipbuilding Industry Standard of the People's Republic of China
CB/T3254.13254.3-94
Marine Diesel Engine Bench Test
1994-08-—22 Issued
China Shaobo Industry Corporation Issued
1995-05-01 Implementation
1 Main Content and Scope of Application
Shipbuilding Industry Standard of the People's Republic of China
Marine Diesel Engine Bench Test| |tt||Standard environmental conditions and calibration of power, fuel consumption and engine oil consumption
CB/T3254.1—94
Classification number: U44
Replaces CB*3255-85
This standard specifies the standard environmental conditions of marine diesel engines (hereinafter referred to as diesel engines), the calibration methods of power, fuel consumption and engine oil consumption, and the correction methods of power and fuel consumption rate under non-standard environmental conditions. This standard applies to marine main diesel engines (hereinafter referred to as main engines) and auxiliary diesel engines (hereinafter referred to as auxiliary engines). 2 Terminology
2.1. Auxiliary equipment
It refers to the equipment attached to the components of the diesel engine. Those equipment that cannot be operated at the rated power under any circumstances after being removed are not included in the auxiliary equipment (such as fuel injection pumps, exhaust gas turbochargers, air coolers, etc.). 2.2 Basic independent auxiliary equipment
It refers to the equipment that is indispensable for the normal and continuous operation of the diesel engine. Auxiliary equipment that is missing but not driven by the diesel engine, such as oil pumps, cooling water pumps, fuel supply pumps, etc. driven by electric motors.
2.3 Basic auxiliary equipment (hereinafter referred to as basic accessories) is an auxiliary equipment driven by the diesel engine and indispensable for its continuous operation. For example, oil pressure pumps, oil pumps, fuel supply pumps, cooling water pumps, seawater pumps, scavenging pumps, cylinder oil injection pumps, intake silencer filters and exhaust silencers driven by the crankshaft. 2.4 Non-basic auxiliary equipment Equipment (hereinafter referred to as non-basic accessories) is an auxiliary equipment driven by a diesel engine but is not necessary for the normal continuous operation of the diesel engine. For example, the starting air compressor, generator, bilge pump, fire pump, fuel delivery pump and thrust bearing driven by the diesel engine. 2.5 Rated power (or rated power)
The power that a diesel engine can generate under specified conditions as specified by the manufacturer according to its purpose and usage characteristics. 2.6 Indicated power
The total power of the gas in the cylinder acting on the working piston. 2.7 Effective power
The power or the sum of the powers measured at the power output end of one or more crankshafts of a diesel engine. 2.8 Continuous power
Continuous power is the power that a diesel engine can continuously generate under the conditions of specified speed and environmental conditions under the conditions of maintenance and maintenance specified by the manufacturer within the maintenance cycle specified by the manufacturer. Approved by China State Shipbuilding Corporation on August 22, 1994 and implemented on May 1, 1995
2.9 Overload power
CB/T 3254.194
The power greater than the continuous power that can be generated in a certain time limit and degree (according to the purpose of the diesel engine) immediately after continuous power operation under a short-term certain environmental condition.
2.10 Fuel-limited power
The power that can be generated by the diesel engine when the fuel injection quantity is limited by the fuel quantity limiter within the specified time limit under the specified speed and environmental conditions. 2.11 International standard power
The continuous effective power generated by the diesel engine with only basic accessories under the following conditions within the maintenance cycle specified by the manufacturer: measured on the manufacturer's test bench at the specified speed: e
b. Corrected to the specified standard environmental conditions: repaired and maintained according to the requirements specified by the manufacturer. c.
2.12 Standard power in use
The continuous effective power generated by the diesel engine with only basic accessories under the following conditions within the maintenance cycle specified by the manufacturer; measured under the use environment and operating conditions of the diesel engine at the specified speed! Corrected to the use environment and operating conditions; b.
c. Repaired and maintained according to the requirements specified by the manufacturer. 2.13 Power correction
In order to keep the thermal load and (or) engine load of the key chain components of the diesel engine basically unchanged, the power value under one environmental condition is corrected to the power value expected to be issued under another environmental condition. 2.14 Power conversion
The diesel engine does not make any adjustments, and the power value actually measured under test conditions is corrected to the power value expected to be issued under another operating environment.
2.15 Adjustable diesel engine
In order to adapt to different environmental conditions, the diesel engine is adjusted to change the position of the fuel limiter, re-match the turbocharger, change the injection timing and other actual adjustments to keep the thermal load and mechanical load similar to the diesel engine. This type of diesel engine is called an adjustable diesel engine.
2.16 Unadjustable diesel engine
An engine that has been pre-adjusted and therefore no longer requires actual adjustments to adapt to different environmental conditions. 2.17 Rated speed (rated speed)
Corresponds to the speed of the diesel engine at rated power. 3 Standard environmental conditions
When determining the power and fuel consumption rate of a diesel engine, the following standard environmental conditions are used:. Total atmospheric pressure P, 100KPa
b. Ambient temperature T, = 298K;
c. Relative humidity, = 30%;
d. Air cooler inlet water temperature T_=298K, Properties: When T, 298K, 0, = 30%, the water vapor partial pressure is 1KPa, so under standard environmental conditions The dry air partial pressure is 99KPs, 4 Power calibration
4.1 Purpose
The purpose of calibrating power mainly includes the following two points: 1. The manufacturer shall specify the calibrated power value of the diesel engine according to the purpose and usage characteristics of the diesel engine; b. Measure and verify the calibrated power value in the same environmental conditions as specified (or after correction under different conditions). 4.2 Method
4.2.1 The power category shall be stated during calibration and classified according to the following methods: a. According to the environmental conditions of power calibration, it is divided into: international standard power or use standard power. The international standard power is the basic required calibrated power value of the diesel engine, and the use standard power can be additionally stated. When the standard power is specified, the environmental conditions and operating conditions should be stated. For example, for main and auxiliary diesel engines installed on ships in unlimited navigation areas, the environmental conditions specified by the International Classification Society (IACS) should be adopted: total atmospheric pressure P,a100KPar
ambient temperature T,=318K,
relative humidity 0,=60%
air cooler water inlet temperature Ta-305K.
b. According to the power usage method, it is divided into: continuous power, overload power or fuel-limited power. Continuous power is the basic required calibrated power value of the diesel engine, and overload power and fuel-limited power can be additionally stated. For marine main engines equipped with fixed-pitch propellers, the manufacturer usually provides a power area diagram that allows continuous operation and short-term operation, see Figure 1. ①- Normal continuous operation area ②- Allowable short-term operation area ③- Overload operation area for special use 4.2.2 The corresponding speed of the diesel engine (rated speed) should be marked when calibrating the power. For diesel engines with reduction gearboxes, the speed calibration should include the crankshaft speed of the diesel engine and the speed of the power output shaft after the reduction gearbox. 4.2.3 If the diesel engine has non-basic accessories or requires independent auxiliary equipment and its power consumption is relatively large, the manufacturer should explain it separately. 4.2.4 The expression method of rated power is: \According to the provisions of CB/T3254.1, the rated power of the engine is ××××KW, which is XXXt/min\. The standard power in 4.2.1.a and the overload power and fuel limit power in 4.2.1.b can be additionally stated. 3
CB/T3254.1-94
Note: The rated power expressed in this way without additional explanation means the international standard power. 4.3 Tolerance of rated power
The manufacturer can specify the tolerance of rated power according to the needs. 5 Calibration of fuel consumption
The reference calorific value of fuel
When calibrating the fuel consumption rate, the reference diesel engine low calorific value of 42700KJ/Kg should be used as the basis. 5.2 Calibration of fuel consumption rate
5.2.1 The fuel consumption rate should be calibrated after the specified period. The unit is g/(KW.h) 5.2.2 The fuel consumption rate of the diesel engine under the following working conditions should be calibrated a Calibration working condition:
b. For diesel engines in special use occasions, the working condition shall be determined by the manufacturer and the user according to their use conditions. 5.2.3 When the lower calorific value of the fuel actually used in the fuel consumption calibration test does not conform to the lower calorific value of the reference fuel, the formula (1) shall be used for conversion: b-bxbzxz.net
Where, bs--the fuel consumption rate calibrated according to the lower calorific value of the reference fuel g/(KW.b), br--the fuel consumption rate actually measured during the calibration test, g/(KW.h), H--the lower calorific value of the fuel used during the calibration test, KJ/Kg! H--the lower calorific value of the reference fuel, KJ/Kg.
5.3 Tolerance of fuel consumption
Except for other Unless otherwise specified, the fuel consumption rate at rated power is allowed to have a deviation of no more than 10% for medium and high speed diesel engines, and no more than +3% for low speed diesel engines.
6 Calibration of engine oil consumption
6.1 Engine oil consumption is expressed as engine oil consumption rate, the unit is g/(KW.h) 6.2 Engine oil consumption rate should be calibrated under the rated working conditions. 6.3 Engine oil consumption rate should be calibrated after the meal period specified in the instruction manual. For diesel engines with separate cylinder fuel supply system, cylinder oil consumption should be calculated uniformly.
6.4 The oil discarded when changing the engine oil should not be included in the calibrated engine oil consumption. 6.5 The brand of engine oil used should be stated.
7 Adjustable diesel engine power and fuel consumption rate correction method 7.1 Power correction under non-adjustable environmental conditions shall be carried out in accordance with the following provisions: When the diesel engine is running under environmental conditions different from the standard environmental conditions specified in Chapter 4 and the power needs to be calculated, if the manufacturer does not provide any other calculation method, formula (2) (3) (4) can be used for calculation. P,aap.
a=K-0. 7(1-K)(元
P.-ao.Pe)
.....(2)
(宗)().
In formulas (2)~(4),
CB/T 3254.194
P,—Efficiency under on-site environmental conditions, KW; Power correction coefficient:
Effective power under standard environmental conditions, KW; -Indicated power ratio:
Energy efficiency:
Indicated power under on-site environmental conditions, KW; Pu-
Indicated power under standard environmental conditions, KW; .-Total atmospheric pressure under on-site environmental conditions, KPaP.
Relative humidity under on-site environment;
Saturated vapor pressure under on-site environmental conditions, KPatPSaturated vapor pressure under standard environmental conditions, KPa; T.
-Environmental temperature under on-site environmental conditions, K; T. Air cooler inlet water temperature under standard environmental conditions, K, T
Air cooler inlet water temperature under on-site environmental conditions, K. b. If the turbocharger speed, turbocharger turbine inlet pressure and cylinder maximum combustion pressure of the diesel engine have not exceeded the specified limits under the rated power, the manufacturer may propose an alternative reference environmental condition as the basis for power correction calculation. In this case, it is calculated according to formula (5)(6)(7). P,aP.
Formula (5)~(7) Where,
P. ——Total atmospheric pressure under alternative reference environmental condition, KPaT. —Environmental degradation under alternative reference environmental condition, K; T—Air cooler inlet water temperature under alternative reference environmental condition, K, P Effective power under alternative reference environmental condition, KW, \-Pressure ratio under standard environmental condition:
....(6)
Double--The maximum allowable pressure ratio under standard environmental condition determined by the manufacturer. Where the coefficient a and exponents m, a and s are shown in Table 2.
Note: ① The dry air ratio in formula (4) can be found by using the grids A1 and A2 in Appendix A (reference). For calculation examples, please refer to Appendix B (reference) ② When the test site environmental conditions are more favorable than the reference environmental conditions represented by the standard environmental conditions, the calibrated power under the environmental conditions can be limited to the calibrated power under the reference environmental conditions represented by the standard environmental conditions. ② Mechanical efficiency is determined by the manufacturer. Table 2 Coefficients and index values ​​for power correction calculation Non-supercharged diesel engine Low-medium speed four-stroke Turbocharged diesel engine Working conditions Power affected by excess air expansion Power affected by heat load limit Without intercooler With intercooler Working conditions CB/T 3254.194 Note: ① The efficiency and efficiency improvement coefficients given in the table are determined based on the test results of many generally representative diesel engines. If there are no other regulations in the manufacturer, they shall be adopted accordingly. For diesel engines not included in Table 2, the power correction formula shall be determined by the manufacturer. In the working condition code D, for diesel engines whose supercharged air is cooled by cylinder jacket water, the index S can be zero. 7.2 Correction of fuel consumption rate
: 7.2.1 When the aircraft needs to operate under the standard environmental conditions different from those specified in Chapter 3 and the manufacturer does not provide any other calculation method, the correction of fuel consumption rate can be calculated using formula (8) (9). b,pb
In the formula (8)~(9),
-fuel consumption rate under the on-site environmental conditions, g/(KW,b); (8)
b,-fuel consumption rate under the standard environmental conditions or alternative reference environmental conditions, /(KW.h); β-correction coefficient of fuel consumption rate.
7.2.2 When the corrected power is greater than the rated power and the power is not corrected, the correction of fuel consumption rate under equal power conditions can be based on the curve chart provided by the manufacturer after experimental verification, or refer to the formula or table in Appendix C (reference). 8. Conversion method of power and fuel consumption rate of unadjusted diesel engine This method is applicable to high-speed diesel engines with a speed of 2000r/min or above and whose fuel supply is not adjusted with the change of on-site environmental conditions. The manufacturer may also appropriately reduce the applicable speed range based on experience. 8.1. Conversion of effective power under irrelevant environmental conditions Based on the effective power measured under the test environment, the effective power under standard environmental conditions or on-site environmental conditions can be calculated using formula (10) (11):
P,-aXP,
g-(F,)
In formula (10)~(11):
...(10)
P. —Effective power under standard environmental conditions or on-site environmental conditions, KWP, —Measured effective power under test environmental conditions, KW, power conversion coefficient;
f, —Atmospheric factor effect;
Diesel engine characteristic index.
8.1.1 The atmospheric factor f represents the effect of environmental conditions (pressure, temperature and humidity) on the amount of air charged in the diesel engine. It varies with the type of engine. The atmospheric factors of various models are calculated as follows: a: Non-supercharged, mechanically supercharged and turbocharged diesel engines with bleed valves are calculated according to formula (12). P.-oP
Turbocharged diesel engines without intercooler or with air-to-air intercooler are calculated according to formula (13). Calculate, P.-o,P.
P,-@,P
For turbocharged diesel engines whose intercooler cooling medium is diesel engine cylinder liner cooling water, calculate according to formula (14). c.
P,-0,P
In formulas (12) to (14):
P,—total atmospheric pressure under test environment conditions, KPa; 6
...(12)
（14)
CB/T 3254.194
P.-saturated vapor pressure under standard environmental conditions, KPaP,-saturated vapor pressure under test environmental conditions, KPaT, intake ambient temperature under test environmental conditions, K, 9, relative humidity under test environmental conditions. 8.1.2 Diesel engine characteristic index. Depending on the type of engine and the combustion air-fuel ratio corresponding to the oil adjustment, the calculation of the characteristic index f. of various types of engines is as follows:
Four-stroke diesel engine is calculated according to formula (15)(16)(17). &
f_m0.036q1.14
Two-stroke diesel engine is calculated according to formula (18). Bx10
In formula (15)~(18):
Specific displacement cycle fuel supply, mg/(LC); q
B—Fuel consumption Kg/h
"Total cylinder displacement, L,
Oil engine speed during test, r/min;
....(16)
（18)
-Compression ratio under standard environmental conditions (for non-supercharged diesel engine-1, two-stage supercharged diesel engine is the total compression ratio). The applicable range of formula (15) (see Figure 2) is 37.23 Tolerance of fuel consumption rate
Unless otherwise specified, the fuel consumption rate at rated power is allowed to have a deviation of no more than 10 5% for medium and high speed diesel engines, and no more than +3% for low speed diesel engines.
6 Calibration of engine oil consumption
6.1 Engine oil consumption is expressed as engine oil consumption rate, the unit is g/(KW.h)6.2 Engine oil consumption rate should be calibrated under the calibrated working conditions.6.3 Engine oil consumption rate should be calibrated after the meal period specified in the instruction manual. For diesel engines with separate cylinder fuel supply system, cylinder oil consumption should be calculated uniformly.
6.4 The oil discarded when changing the engine oil should not be included in the calibrated engine oil consumption.6.5 The brand of engine oil used should be stated.
7 Adjustable diesel engine power and fuel consumption rate correction method 7.1 Power correction under non-adjustable environmental conditions shall be carried out in accordance with the following provisions: When the diesel engine is running under environmental conditions different from the standard environmental conditions specified in Chapter 4 and the power needs to be calculated, if the manufacturer does not provide any other calculation method, formula (2) (3) (4) can be used for calculation. P,aap.
a=K-0. 7(1-K)(元
P.-ao.Pe)
.....(2)
(宗)().
In formulas (2)~(4),
CB/T 3254.194
P,—Efficiency under on-site environmental conditions, KW; Power correction coefficient:
Effective power under standard environmental conditions, KW; -Indicated power ratio:
Energy efficiency:
Indicated power under on-site environmental conditions, KW; Pu-
Indicated power under standard environmental conditions, KW; .-Total atmospheric pressure under on-site environmental conditions, KPaP.
Relative humidity under on-site environment;
Saturated vapor pressure under on-site environmental conditions, KPatPSaturated vapor pressure under standard environmental conditions, KPa; T.
-Environmental temperature under on-site environmental conditions, K; T. Air cooler inlet water temperature under standard environmental conditions, K, T
Air cooler inlet water temperature under on-site environmental conditions, K. b. If the turbocharger speed, turbocharger turbine inlet pressure and cylinder maximum combustion pressure of the diesel engine have not exceeded the specified limits under the rated power, the manufacturer may propose an alternative reference environmental condition as the basis for power correction calculation. In this case, it is calculated according to formula (5)(6)(7). P,aP.
Formula (5)~(7) Where,
P. ——Total atmospheric pressure under alternative reference environmental condition, KPaT. —Environmental degradation under alternative reference environmental condition, K; T—Air cooler inlet water temperature under alternative reference environmental condition, K, P Effective power under alternative reference environmental condition, KW, \-Pressure ratio under standard environmental condition:
....(6)
Double--The maximum allowable pressure ratio under standard environmental condition determined by the manufacturer. Where the coefficient a and exponents m, a and s are shown in Table 2.
Note: ① The dry air ratio in formula (4) can be found by using the grids A1 and A2 in Appendix A (reference). For calculation examples, please refer to Appendix B (reference) ② When the test site environmental conditions are more favorable than the reference environmental conditions represented by the standard environmental conditions, the calibrated power under the environmental conditions can be limited to the calibrated power under the reference environmental conditions represented by the standard environmental conditions. ② Mechanical efficiency is determined by the manufacturer. Table 2 Coefficients and index values ​​for power correction calculation Non-supercharged diesel engine Low-medium speed four-stroke Turbocharged diesel engine Working conditions Power affected by excess air expansion Power affected by heat load limit Without intercooler With intercooler Working conditions CB/T 3254.194 Note: ① The efficiency and efficiency improvement coefficients given in the table are determined based on the test results of many generally representative diesel engines. If there are no other regulations in the manufacturer, they shall be adopted accordingly. For diesel engines not included in Table 2, the power correction formula shall be determined by the manufacturer. In the working condition code D, for diesel engines whose supercharged air is cooled by cylinder jacket water, the index S can be zero. 7.2 Correction of fuel consumption rate
: 7.2.1 When the aircraft needs to operate under the standard environmental conditions different from those specified in Chapter 3 and the manufacturer does not provide any other calculation method, the correction of fuel consumption rate can be calculated using formula (8) (9). b,pb
In the formula (8)~(9),
-fuel consumption rate under the on-site environmental conditions, g/(KW,b); (8)
b,-fuel consumption rate under the standard environmental conditions or alternative reference environmental conditions, /(KW.h); β-correction coefficient of fuel consumption rate.
7.2.2 When the corrected power is greater than the rated power and the power is not corrected, the correction of fuel consumption rate under equal power conditions can be based on the curve chart provided by the manufacturer after experimental verification, or refer to the formula or table in Appendix C (reference). 8. Conversion method of power and fuel consumption rate of unadjusted diesel engine This method is applicable to high-speed diesel engines with a speed of 2000r/min or above and whose fuel supply is not adjusted with the change of on-site environmental conditions. The manufacturer may also appropriately reduce the applicable speed range based on experience. 8.1. Conversion of effective power under irrelevant environmental conditions Based on the effective power measured under the test environment, the effective power under standard environmental conditions or on-site environmental conditions can be calculated using formula (10) (11):
P,-aXP,
g-(F,)
In formula (10)~(11):
...(10)
P. —Effective power under standard environmental conditions or on-site environmental conditions, KWP, —Measured effective power under test environmental conditions, KW, power conversion coefficient;
f, —Atmospheric factor effect;
Diesel engine characteristic index.
8.1.1 The atmospheric factor f represents the effect of environmental conditions (pressure, temperature and humidity) on the amount of air charged in the diesel engine. It varies with the type of engine. The atmospheric factors of various models are calculated as follows: a: Non-supercharged, mechanically supercharged and turbocharged diesel engines with bleed valves are calculated according to formula (12). P.-oP
Turbocharged diesel engines without intercooler or with air-to-air intercooler are calculated according to formula (13). Calculate, P.-o,P.
P,-@,P
For turbocharged diesel engines whose intercooler cooling medium is diesel engine cylinder liner cooling water, calculate according to formula (14). c.
P,-0,P
In formulas (12) to (14):
P,—total atmospheric pressure under test environment conditions, KPa; 6
...(12)
（14)
CB/T 3254.194
P.-saturated vapor pressure under standard environmental conditions, KPaP,-saturated vapor pressure under test environmental conditions, KPaT, intake ambient temperature under test environmental conditions, K, 9, relative humidity under test environmental conditions. 8.1.2 Diesel engine characteristic index. Depending on the type of engine and the combustion air-fuel ratio corresponding to the oil adjustment, the calculation of the characteristic index f. of various types of engines is as follows:
Four-stroke diesel engine is calculated according to formula (15)(16)(17). &
f_m0.036q1.14
Two-stroke diesel engine is calculated according to formula (18). Bx10
In formula (15)~(18):
Specific displacement cycle fuel supply, mg/(LC); q
B—Fuel consumption Kg/h
"Total cylinder displacement, L,
Oil engine speed during test, r/min;
....(16)
（18)
-Compression ratio under standard environmental conditions (for non-supercharged diesel engine-1, two-stage supercharged diesel engine is the total compression ratio). The applicable range of formula (15) (see Figure 2) is 37.23 Tolerance of fuel consumption rate
Unless otherwise specified, the fuel consumption rate at rated power is allowed to have a deviation of no more than 10 5% for medium and high speed diesel engines, and no more than +3% for low speed diesel engines.
6 Calibration of engine oil consumption
6.1 Engine oil consumption is expressed as engine oil consumption rate, the unit is g/(KW.h)6.2 Engine oil consumption rate should be calibrated under the calibrated working conditions.6.3 Engine oil consumption rate should be calibrated after the meal period specified in the instruction manual. For diesel engines with separate cylinder fuel supply system, cylinder oil consumption should be calculated uniformly.
6.4 The oil discarded when changing the engine oil should not be included in the calibrated engine oil consumption.6.5 The brand of engine oil used should be stated.
7 Adjustable diesel engine power and fuel consumption rate correction method 7.1 Power correction under non-adjustable environmental conditions shall be carried out in accordance with the following provisions: When the diesel engine is running under environmental conditions different from the standard environmental conditions specified in Chapter 4 and the power needs to be calculated, if the manufacturer does not provide any other calculation method, formula (2) (3) (4) can be used for calculation. P,aap.
a=K-0. 7(1-K)(元
P.-ao.Pe)
.....(2)
(宗)().
In formulas (2)~(4),
CB/T 3254.194
P,—Efficiency under on-site environmental conditions, KW; Power correction coefficient:
Effective power under standard environmental conditions, KW; -Indicated power ratio:
Energy efficiency:
Indicated power under on-site environmental conditions, KW; Pu-
Indicated power under standard environmental conditions, KW; .-Total atmospheric pressure under on-site environmental conditions, KPaP.
Relative humidity under on-site environment;
Saturated vapor pressure under on-site environmental conditions, KPatPSaturated vapor pressure under standard environmental conditions, KPa; T.
-Environmental temperature under on-site environmental conditions, K; T. Air cooler inlet water temperature under standard environmental conditions, K, T
Air cooler inlet water temperature under on-site environmental conditions, K. b. If the turbocharger speed, turbocharger turbine inlet pressure and cylinder maximum combustion pressure of the diesel engine have not exceeded the specified limits under the rated power, the manufacturer may propose an alternative reference environmental condition as the basis for power correction calculation. In this case, it is calculated according to formula (5)(6)(7). P,aP.
Formula (5)~(7) Where,
P. ——Total atmospheric pressure under alternative reference environmental condition, KPaT. —Environmental degradation under alternative reference environmental condition, K; T—Air cooler inlet water temperature under alternative reference environmental condition, K, P Effective power under alternative reference environmental condition, KW, \-Pressure ratio under standard environmental condition:
....(6)
Double--The maximum allowable pressure ratio under standard environmental condition determined by the manufacturer. Where the coefficient a and exponents m, a and s are shown in Table 2.
Note: ① The dry air ratio in formula (4) can be found by using the grids A1 and A2 in Appendix A (reference). For calculation examples, please refer to Appendix B (reference) ② When the test site environmental conditions are more favorable than the reference environmental conditions represented by the standard environmental conditions, the calibrated power under the environmental conditions can be limited to the calibrated power under the reference environmental conditions represented by the standard environmental conditions. ② Mechanical efficiency is determined by the manufacturer. Table 2 Coefficients and index values ​​for power correction calculation Non-supercharged diesel engine Low-medium speed four-stroke Turbocharged diesel engine Working conditions Power affected by excess air expansion Power affected by heat load limit Without intercooler With intercooler Working conditions CB/T 3254.194 Note: ① The efficiency and efficiency improvement coefficients given in the table are determined based on the test results of many generally representative diesel engines. If there are no other regulations in the manufacturer, they shall be adopted accordingly. For diesel engines not included in Table 2, the power correction formula shall be determined by the manufacturer. In the working condition code D, for diesel engines whose supercharged air is cooled by cylinder jacket water, the index S can be zero. 7.2 Correction of fuel consumption rate
: 7.2.1 When the aircraft needs to operate under the standard environmental conditions different from those specified in Chapter 3 and the manufacturer does not provide any other calculation method, the correction of fuel consumption rate can be calculated using formula (8) (9). b,pb
In the formula (8)~(9),
-fuel consumption rate under the on-site environmental conditions, g/(KW,b); (8)
b,-fuel consumption rate under the standard environmental conditions or alternative reference environmental conditions, /(KW.h); β-correction coefficient of fuel consumption rate.
7.2.2 When the corrected power is greater than the rated power and the power is not corrected, the correction of fuel consumption rate under equal power conditions can be based on the curve chart provided by the manufacturer after experimental verification, or refer to the formula or table in Appendix C (reference). 8. Conversion method of power and fuel consumption rate of unadjusted diesel engine This method is applicable to high-speed diesel engines with a speed of 2000r/min or above and whose fuel supply is not adjusted with the change of on-site environmental conditions. The manufacturer may also appropriately reduce the applicable speed range based on experience. 8.1. Conversion of effective power under irrelevant environmental conditions Based on the effective power measured under the test environment, the effective power under standard environmental conditions or on-site environmental conditions can be calculated using formula (10) (11):
P,-aXP,
g-(F,)
In formula (10)~(11):
...(10)
P. —Effective power under standard environmental conditions or on-site environmental conditions, KWP, —Measured effective power under test environmental conditions, KW, power conversion coefficient;
f, —Atmospheric factor effect;
Diesel engine characteristic index.
8.1.1 The atmospheric factor f represents the effect of environmental conditions (pressure, temperature and humidity) on the amount of air charged in the diesel engine. It varies with the type of engine. The atmospheric factors of various models are calculated as follows: a: Non-supercharged, mechanically supercharged and turbocharged diesel engines with bleed valves are calculated according to formula (12). P.-oP
Turbocharged diesel engines without intercooler or with air-to-air intercooler are calculated according to formula (13). Calculate, P.-o,P.
P,-@,P
For turbocharged diesel engines whose intercooler cooling medium is diesel engine cylinder liner cooling water, calculate according to formula (14). c.
P,-0,P
In formulas (12) to (14):
P,—total atmospheric pressure under test environment conditions, KPa; 6
...(12)
（14)
CB/T 3254.194
P.-saturated vapor pressure under standard environmental conditions, KPaP,-saturated vapor pressure under test environmental conditions, KPaT, intake ambient temperature under test environmental conditions, K, 9, relative humidity under test environmental conditions. 8.1.2 Diesel engine characteristic index. Depending on the type of engine and the combustion air-fuel ratio corresponding to the oil adjustment, the calculation of the characteristic index f. of various types of engines is as follows:
Four-stroke diesel engine is calculated according to formula (15)(16)(17). &
f_m0.036q1.14
Two-stroke diesel engine is calculated according to formula (18). Bx10
In formula (15)~(18):
Specific displacement cycle fuel supply, mg/(LC); q
B—Fuel consumption Kg/h
"Total cylinder displacement, L,
Oil engine speed during test, r/min;
....(16)
（18)
-Compression ratio under standard environmental conditions (for non-supercharged diesel engine-1, two-stage supercharged diesel engine is the total compression ratio). The applicable range of formula (15) (see Figure 2) is 37.21 Power correction under non-standard environmental conditions shall be carried out in accordance with the following provisions: When the diesel engine is operated under standard environmental conditions different from those specified in Chapter 4 and the power needs to be calculated, if the manufacturer does not provide any other calculation method, formula (2) (3) (4) can be used for calculation. P,aap.
a=K-0.7(1-K)(元
P.-ao.Pe)
.....(2)
(宗)().
In formulas (2)~(4),
CB/T 3254.194
P,—Efficiency under on-site environmental conditions, KW; Power correction coefficient:
Effective power under standard environmental conditions, KW; -Indicated power ratio:
Energy efficiency:
Indicated power under on-site environmental conditions, KW; Pu-
Indicated power under standard environmental conditions, KW; .-Total atmospheric pressure under on-site environmental conditions, KPaP.
Relative humidity under on-site environment;
Saturated vapor pressure under on-site environmental conditions, KPatPSaturated vapor pressure under standard environmental conditions, KPa; T.
-Environmental temperature under on-site environmental conditions, K; T. Air cooler inlet water temperature under standard environmental conditions, K, T
Air cooler inlet water temperature under on-site environmental conditions, K. b. If the turbocharger speed, turbocharger turbine inlet pressure and cylinder maximum combustion pressure of the diesel engine have not exceeded the specified limits under the rated power, the manufacturer may propose an alternative reference environmental condition as the basis for power correction calculation. In this case, it is calculated according to formula (5)(6)(7). P,aP.
Formula (5)~(7) Where,
P. ——Total atmospheric pressure under alternative reference environmental condition, KPaT. —Environmental degradation under alternative reference environmental condition, K; T—Air cooler inlet water temperature under alternative reference environmental condition, K, P Effective power under alternative reference environmental condition, KW, \-Pressure ratio under standard environmental condition:
....(6)
Double--The maximum allowable pressure ratio under standard environmental condition determined by the manufacturer. Where the coefficient a and exponents m, a and s are shown in Table 2.
Note: ① The dry air ratio in formula (4) can be found by using the grids A1 and A2 in Appendix A (reference). For calculation examples, please refer to Appendix B (reference) ② When the test site environmental conditions are more favorable than the reference environmental conditions represented by the standard environmental conditions, the calibrated power under the environmental conditions can be limited to the calibrated power under the reference environmental conditions represented by the standard environmental conditions. ② Mechanical efficiency is determined by the manufacturer. Table 2 Coefficients and index values ​​for power correction calculation Non-supercharged diesel engine Low-medium speed four-stroke Turbocharged diesel engine Working conditions Power affected by excess air expansion Power affected by heat load limit Without intercooler With intercooler Working conditions CB/T 3254.194 Note: ① The efficiency and efficiency improvement coefficients given in the table are determined based on the test results of many generally representative diesel engines. If there are no other regulations in the manufacturer, they shall be adopted accordingly. For diesel engines not included in Table 2, the power correction formula shall be determined by the manufacturer. In the working condition code D, for diesel engines whose supercharged air is cooled by cylinder jacket water, the index S can be zero. 7.2 Correction of fuel consumption rate
: 7.2.1 When the aircraft needs to operate under the standard environmental conditions different from those specified in Chapter 3 and the manufacturer does not provide any other calculation method, the correction of fuel consumption rate can be calculated using formula (8) (9). b,pb
In the formula (8)~(9),
-fuel consumption rate under the on-site environmental conditions, g/(KW,b); (8)
b,-fuel consumption rate under the standard environmental conditions or alternative reference environmental conditions, /(KW.h); β-correction coefficient of fuel consumption rate.
7.2.2 When the corrected power is greater than the rated power and the power is not corrected, the correction of fuel consumption rate under equal power conditions can be based on the curve chart provided by the manufacturer after experimental verification, or refer to the formula or table in Appendix C (reference). 8. Conversion method of power and fuel consumption rate of unadjusted diesel engine This method is applicable to high-speed diesel engines with a speed of 2000r/min or above and whose fuel supply is not adjusted with the change of on-site environmental conditions. The manufacturer may also appropriately reduce the applicable speed range based on experience. 8.1. Conversion of effective power under irrelevant environmental conditions Based on the effective power measured under the test environment, the effective power under standard environmental conditions or on-site environmental conditions can be calculated using formula (10) (11):
P,-aXP,
g-(F,)
In formula (10)~(11):
...(10)
P. —Effective power under standard environmental conditions or on-site environmental conditions, KWP, —Measured effective power under test environmental conditions, KW, power conversion coefficient;
f, —Atmospheric factor effect;
Diesel engine characteristic index.
8.1.1 The atmospheric factor f represents the effect of environmental conditions (pressure, temperature and humidity) on the amount of air charged in the diesel engine. It varies with the type of engine. The atmospheric factors of various models are calculated as follows: a: Non-supercharged, mechanically supercharged and turbocharged diesel engines with bleed valves are calculated according to formula (12). P.-oP
Turbocharged diesel engines without intercooler or with air-to-air intercooler are calculated according to formula (13). Calculate, P.-o,P.
P,-@,P
For turbocharged diesel engines whose intercooler cooling medium is diesel engine cylinder liner cooling water, calculate according to formula (14). c.
P,-0,P
In formulas (12) to (14):
P,—total atmospheric pressure under test environment conditions, KPa; 6
...(12)
（14)
CB/T 3254.194
P.-saturated vapor pressure under standard environmental conditions, KPaP,-saturated vapor pressure under test environmental conditions, KPaT, intake ambient temperature under test environmental conditions, K, 9, relative humidity under test environmental conditions. 8.1.2 Diesel engine characteristic index. Depending on the type of engine and the combustion air-fuel ratio corresponding to the oil adjustment, the calculation of the characteristic index f. of various types of engines is as follows:
Four-stroke diesel engine is calculated according to formula (15)(16)(17). &
f_m0.036q1.14
Two-stroke diesel engine is calculated according to formula (18). Bx10
In formula (15)~(18):
Specific displacement cycle fuel supply, mg/(LC); q
B—Fuel consumption Kg/h
"Total cylinder displacement, L,
Oil engine speed during test, r/min;
....(16)
（18)
-Compression ratio under standard environmental conditions (for non-supercharged diesel engine-1, two-stage supercharged diesel engine is the total compression ratio). The applicable range of formula (15) (see Figure 2) is 37.21 Power correction under non-standard environmental conditions shall be carried out in accordance with the following provisions: When the diesel engine is operated under standard environmental conditions different from those specified in Chapter 4 and the power needs to be calculated, if the manufacturer does not provide any other calculation method, formula (2) (3) (4) can be used for calculation. P,aap.
a=K-0.7(1-K)(元
P.-ao.Pe)
.....(2)
(宗)().
In formulas (2)~(4),
CB/T 3254.194
P,—Efficiency under on-site environmental conditions, KW; Power correction coefficient:
Effective power under standard environmental conditions, KW; -Indicated power ratio:
Energy efficiency:
Indicated power under on-site environmental conditions, KW; Pu-
Indicated power under standard environmental conditions, KW; .-Total atmospheric pressure under on-site environmental conditions, KPaP.
Relative humidity under on-site environment;
Saturated vapor pressure under on-site environmental conditions, KPatPSaturated vapor pressure under standard environmental conditions, KPa; T.
-Environmental temperature under on-site environmental conditions, K; T. Air cooler inlet water temperature under standard environmental conditions, K, T
Air cooler inlet water temperature under on-site environmental conditions, K. b. If the turbocharger speed, turbocharger turbine inlet pressure and cylinder maximum combustion pressure of the diesel engine have not exceeded the specified limits under the rated power, the manufacturer may propose an alternative reference environmental condition as the basis for power correction calculation. In this case, it is calculated according to formula (5)(6)(7). P,aP.
Formula (5)~(7) Where,
P. ——Total atmospheric pressure under alternative reference environmental condition, KPaT. —Environmental degradation under alternative reference environmental condition, K; T—Air cooler inlet water temperature under alternative reference environmental condition, K, P Effective power under alternative reference environmental condition, KW, \-Pressure ratio under standard environmental condition:
....(6)
Double--The maximum allowable pressure ratio under standard environmental condition determined by the manufacturer. Where the coefficient a and exponents m, a and s are shown in Table 2.
Note: ① The dry air ratio in formula (4) can be found by using the grids A1 and A2 in Appendix A (reference). For calculation examples, please refer to Appendix B (reference) ② When the test site environmental conditions are more favorable than the reference environmental conditions represented by the standard environmental conditions, the calibrated power under the environmental conditions can be limited to the calibrated power under the reference environmental conditions represented by the standard environmental conditions. ② Mechanical efficiency is determined by the manufacturer. Table 2 Coefficients and index values ​​for power correction calculation Non-supercharged diesel engine Low-medium speed four-stroke Turbocharged diesel engine Working conditions Power affected by excess air expansion Power affected by heat load limit Without intercooler With intercooler Working conditions CB/T 3254.194 Note: ① The efficiency and efficiency improvement coefficients given in the table are determined based on the test results of many generally representative diesel engines. If there are no other regulations in the manufacturer, they shall be adopted accordingly. For diesel engines not included in Table 2, the power correction formula shall be determined by the manufacturer. In the working condition code D, for diesel engines whose supercharged air is cooled by cylinder jacket water, the index S can be zero. 7.2 Correction of fuel consumption rate
: 7.2.1 When the aircraft needs to operate under the standard environmental conditions different from those specified in Chapter 3 and the manufacturer does not provide any other calculation method, the correction of fuel consumption rate can be calculated using formula (8) (9). b,pb
In the formula (8)~(9),
-fuel consumption rate under the on-site environmental conditions, g/(KW,b); (8)
b,-fuel consumption rate under the standard environmental conditions or alternative reference environmental conditions, /(KW.h); β-correction coefficient of fuel consumption rate.
7.2.2 When the corrected power is greater than the rated power and the power is not corrected, the correction of fuel consumption rate under equal power conditions can be based on the curve chart provided by the manufacturer after experimental verification, or refer to the formula or table in Appendix C (reference). 8. Conversion method of power and fuel consumption rate of unadjusted diesel engine This method is applicable to high-speed diesel engines with a speed of 2000r/min or above and whose fuel supply is not adjusted with the change of on-site environmental conditions. The manufacturer may also appropriately reduce the applicable speed range based on experience. 8.1. Conversion of effective power under irrelevant environmental conditions Based on the effective power measured under the test environment, the effective power under standard environmental conditions or on-site environmental conditions can be calculated using formula (10) (11):
P,-aXP,
g-(F,)
In formula (10)~(11):
...(10)
P. —Effective power under standard environmental conditions or on-site environmental conditions, KWP, —Measured effective power under test environmental conditions, KW, power conversion coefficient;
f, —Atmospheric factor effect;
Diesel engine characteristic index.
8.1.1 The atmospheric factor f represents the effect of environmental conditions (pressure, temperature and humidity) on the amount of air charged in the diesel engine. It varies with the type of engine. The atmospheric factors of various models are calculated as follows: a: Non-supercharged, mechanically supercharged and turbocharged diesel engines with bleed valves are calculated according to formula (12). P.-oP
Turbocharged diesel engines without intercooler or with air-to-air intercooler are calculated according to formula (13). Calculate, P.-o,P.
P,-@,P
For turbocharged diesel engines whose intercooler cooling medium is diesel engine cylinder liner cooling water, calculate according to formula (14). c.
P,-0,P
In formulas (12) to (14):
P,—total atmospheric pressure under test environment conditions, KPa; 6
...(12)
（14)
CB/T 3254.194
P.-saturated vapor pressure under standard environmental conditions, KPaP,-saturated vapor pressure under test environmental conditions, KPaT, intake ambient temperature under test environmental conditions, K, 9, relative humidity under test environmental conditions. 8.1.2 Diesel engine characteristic index. Depending on the type of engine and the combustion air-fuel ratio corresponding to the oil adjustment, the calculation of the characteristic index f. of various types of engines is as follows:
Four-stroke diesel engine is calculated according to formula (15)(16)(17). &
f_m0.036q1.14
Two-stroke diesel engine is calculated according to formula (18). Bx10
In formula (15)~(18):
Specific displacement cycle fuel supply, mg/(LC); q
B—Fuel consumption Kg/h
"Total cylinder displacement, L,
Oil engine speed during test, r/min;
....(16)
（18)
-Compression ratio under standard environmental conditions (for non-supercharged diesel engine-1, two-stage supercharged diesel engine is the total compression ratio). The applicable range of formula (15) (see Figure 2) is 37.2
——Environmental temperature under on-site environmental conditions, K; T. Air cooler inlet water temperature under standard environmental conditions, K, T
Air cooler inlet water temperature under on-site environmental conditions, K. b. If the turbocharger speed, turbocharger turbine inlet speed and cylinder maximum combustion pressure of the diesel engine under rated power have not exceeded the specified limits, the manufacturer may propose an alternative reference environmental condition as the basis for power correction calculation. In this case, calculate according to formula (5)(6)(7). P, aP.
In formula (5)~(7),
P. ——Total atmospheric pressure under alternative reference environmental conditions, KPaT. —Environmental degradation under alternative reference environmental conditions, K; T—Air cooler inlet water temperature under alternative reference environmental conditions, K, P—Effective power under alternative reference environmental conditions, KW, \-Pressure ratio under standard environmental conditions:
....(6)
双一—The maximum allowable pressure ratio under standard environmental conditions determined by the manufacturer. The coefficient a and the exponents m, a and s are shown in Table 2.
Note: ① The dry air ratio in formula (4) can be found by using the grids A1 and A2 in Appendix A (reference). For calculation examples, refer to Appendix B (reference) ② When the test site environmental conditions are more favorable than the reference environmental conditions of the standard environmental conditions, the calibrated power under the environmental conditions can be limited to the calibrated power under the standard environmental conditions that replace the reference environmental conditions. ② Mechanical efficiency is determined by the manufacturer. Table 2 Coefficients and index values ​​for power correction calculation Non-supercharged diesel engine Low-medium speed four-stroke Turbocharged diesel engine Working conditions Power affected by excess air expansion Power affected by heat load limit Without intercooler With intercooler Working conditions CB/T 3254.194 Note: ① The efficiency and efficiency improvement coefficients given in the table are determined based on the test results of many generally representative diesel engines. If there are no other regulations in the manufacturer, they shall be adopted accordingly. For diesel engines not included in Table 2, the power correction formula shall be determined by the manufacturer. In the working condition code D, for diesel engines whose supercharged air is cooled by cylinder jacket water, the index S can be zero. 7.2 Correction of fuel consumption rate
: 7.2.1 When the aircraft needs to operate under the standard environmental conditions different from those specified in Chapter 3 and the manufacturer does not provide any other calculation method, the correction of fuel consumption rate can be calculated using formula (8) (9). b,pb
In the formula (8)~(9),
-fuel consumption rate under the on-site environmental conditions, g/(KW,b); (8)
b,-fuel consumption rate under the standard environmental conditions or alternative reference environmental conditions, /(KW.h); β-correction coefficient of fuel consumption rate.
7.2.2 When the corrected power is greater than the rated power and the power is not corrected, the correction of fuel consumption rate under equal power conditions can be based on the curve chart provided by the manufacturer after experimental verification, or refer to the formula or table in Appendix C (reference). 8. Conversion method of power and fuel consumption rate of unadjusted diesel engine This method is applicable to high-speed diesel engines with a speed of 2000r/min or above and whose fuel supply is not adjusted with the change of on-site environmental conditions. The manufacturer may also appropriately reduce the applicable speed range based on experience. 8.1. Conversion of effective power under irrelevant environmental conditions Based on the effective power measured under the test environment, the effective power under standard environmental conditions or on-site environmental conditions can be calculated using formula (10) (11):
P,-aXP,
g-(F,)
In formula (10)~(11):
...(10)
P. —Effective power under standard environmental conditions or on-site environmental conditions, KWP, —Measured effective power under test environmental conditions, KW, power conversion coefficient;
f, —Atmospheric factor effect;
Diesel engine characteristic index.
8.1.1 The atmospheric factor f represents the effect of environmental conditions (pressure, temperature and humidity) on the amount of air charged in the diesel engine. It varies with the type of engine. The atmospheric factors of various models are calculated as follows: a: Non-supercharged, mechanically supercharged and turbocharged diesel engines with bleed valves are calculated according to formula (12). P.-oP
Turbocharged diesel engines without intercooler or with air-to-air intercooler are calculated according to formula (13). Calculate, P.-o,P.
P,-@,P
For turbocharged diesel engines whose intercooler cooling medium is diesel engine cylinder liner cooling water, calculate according to formula (14). c.
P,-0,P
In formulas (12) to (14):
P,—total atmospheric pressure under test environment conditions, KPa; 6
...(12)
（14)
CB/T 3254.194
P.-saturated vapor pressure under standard environmental conditions, KPaP,-saturated vapor pressure under test environmental conditions, KPaT, intake ambient temperature under test environmental conditions, K, 9, relative humidity under test environmental conditions. 8.1.2 Diesel engine characteristic index. Depending on the type of engine and the combustion air-fuel ratio corresponding to the oil adjustment, the calculation of the characteristic index f. of various types of engines is as follows:
Four-stroke diesel engine is calculated according to formula (15)(16)(17). &
f_m0.036q1.14
Two-stroke diesel engine is calculated according to formula (18). Bx10
In formula (15)~(18):
Specific displacement cycle fuel supply, mg/(LC); q
B—Fuel consumption Kg/h
"Total cylinder displacement, L,
Oil engine speed during test, r/min;
....(16)
（18)
-Compression ratio under standard environmental conditions (for non-supercharged diesel engine-1, two-stage supercharged diesel engine is the total compression ratio). The applicable range of formula (15) (see Figure 2) is 37.2
——Environmental temperature under on-site environmental conditions, K; T. Air cooler inlet water temperature under standard environmental conditions, K, T
Air cooler inlet water temperature under on-site environmental conditions, K. b. If the turbocharger speed, turbocharger turbine inlet speed and cylinder maximum combustion pressure of the diesel engine under rated power have not exceeded the specified limits, the manufacturer may propose an alternative reference environmental condition as the basis for power correction calculation. In this case, calculate according to formula (5)(6)(7). P, aP.
In formula (5)~(7),
P. ——Total atmospheric pressure under alternative reference environmental conditions, KPaT. —Environmental degradation under alternative reference environmental conditions, K; T—Air cooler inlet water temperature under alternative reference environmental conditions, K, P—Effective power under alternative reference environmental conditions, KW, \-Pressure ratio under standard environmental conditions:
....(6)
双一—The maximum allowable pressure ratio under standard environmental conditions determined by the manufacturer. The coefficient a and the exponents m, a and s are shown in Table 2.
Note: ① The dry air ratio in formula (4) can be found by using the grids A1 and A2 in Appendix A (reference). For calculation examples, refer to Appendix B (reference) ② When the test site environmental conditions are more favorable than the reference environmental conditions of the standard environmental conditions, the calibrated power under the environmental conditions can be limited to the calibrated power under the standard environmental conditions that replace the reference environmental conditions. ② Mechanical efficiency is determined by the manufacturer. Table 2 Coefficients and index values ​​for power correction calculation Non-supercharged diesel engine Low-medium speed four-stroke Turbocharged diesel engine Working conditions Power affected by excess air expansion Power affected by heat load limit Without intercooler With intercooler Working conditions CB/T 3254.194 Note: ① The efficiency and efficiency improvement coefficients given in the table are determined based on the test results of many generally representative diesel engines. If there are no other regulations in the manufacturer, they shall be adopted accordingly. For diesel engines not included in Table 2, the power correction formula shall be determined by the manufacturer. In the working condition code D, for diesel engines whose supercharged air is cooled by cylinder jacket water, the index S can be zero. 7.2 Correction of fuel consumption rate
: 7.2.1 When the aircraft needs to operate under the standard environmental conditions different from those specified in Chapter 3 and the manufacturer does not provide any other calculation method, the correction of fuel consumption rate can be calculated using formula (8) (9). b,pb
In the formula (8)~(9),
-fuel consumption rate under the on-site environmental conditions, g/(KW,b); (8)
b,-fuel consumption rate under the standard environmental conditions or alternative reference environmental conditions, /(KW.h); β-correction coefficient of fuel consumption rate.
7.2.2 When the corrected power is greater than the rated power and the power is not corrected, the correction of fuel consumption rate under equal power conditions can be based on the curve chart provided by the manufacturer after experimental verification, or refer to the formula or table in Appendix C (reference). 8. Conversion method of power and fuel consumption rate of unadjusted diesel engine This method is applicable to high-speed diesel engines with a speed of 2000r/min or above and whose fuel supply is not adjusted with the change of on-site environmental conditions. The manufacturer may also appropriately reduce the applicable speed range based on experience. 8.1. Conversion of effective power under irrelevant environmental conditions Based on the effective power measured under the test environment, the effective power under standard environmental conditions or on-site environmental conditions can be calculated using formula (10) (11):
P,-aXP,
g-(F,)
In formula (10)~(11):
...(10)
P. —Effective power under standard environmental conditions or on-site environmental conditions, KWP, —Measured effective power under test environmental conditions, KW, power conversion coefficient;
f, —Atmospheric factor effect;
Diesel engine characteristic index.
8.1.1 The atmospheric factor f represents the effect of environmental conditions (pressure, temperature and humidity) on the amount of air charged in the diesel engine. It varies with the type of engine. The atmospheric factors of various models are calculated as follows: a: Non-supercharged, mechanically supercharged and turbocharged diesel engines with bleed valves are calculated according to formula (12). P.-oP
Turbocharged diesel engines without intercooler or with air-to-air intercooler are calculated according to formula (13). Calculate, P.-o,P.
P,-@,P
For turbocharged diesel engines whose intercooler cooling medium is diesel engine cylinder liner cooling water, calculate according to formula (14). c.
P,-0,P
In formulas (12) to (14):
P,—total atmospheric pressure under test environment conditions, KPa; 6
...(12)
（14)
CB/T 3254.194
P.-saturated vapor pressure under standard environmental conditions, KPaP,-saturated vapor pressure under test environmental conditions, KPaT, intake ambient temperature under test environmental conditions, K, 9, relative humidity under test environmental conditions. 8.1.2 Diesel engine characteristic index. Depending on the type of engine and the combustion air-fuel ratio corresponding to the oil adjustment, the calculation of the characteristic index f. of various types of engines is as follows:
Four-stroke diesel engine is calculated according to for
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