Notes on performance correction - AH00.10-P-2010-01A

Engine 104, 111, 112, 113, 119, 120, 137, 166, 601, 602, 603, 604, 605, 606

General

The weather station's barometer must be calibrated to the air pressure specified by the local meteorological office.

The measured performance value must be corrected with correction factors.

There are two 2 correction factors:

Performance correction formula N _eo = N _e x K _H

N_eo = Performance in reference to normal operating conditions in kW.

N_e = Performance measured on the output dynamometer in kW.

K_H = Correction for intake air temperature, barometer level and altitude of the relevant test location.

Calculation example

Read air pressure, altitude and intake air temperature of the test location off at the weather station.
In the example:

Air pressure of the test location =955 hPa (mbar)

Altitude of the test location = 400 m

Intake air temperature of the test location =+20 °C
Determine the performance on the output dynamometer = 100 kW
In the altitude correction Table, the altitude value of the test location = 400 m, results in a height correction factor of 46 hPa (mbar).
The air pressure of the test location minus the height correction factor results in an air pressure value (p) of: 955 hPa (mbar) - 46 hPa (mbar) = 909 hPa (mbar)
In order to be able to insert the air pressure (p) into the Table, it must be rounded. In the example, to 910 hPa.
On the basis of the air pressure (p) = 910 hPa, we read a correction factor (KH) of 1.0787 off from the performance correction Table with an intake air temperature (t) of 20 °C.
The performance data in relation to normal operating conditions results in the following:
N_eo = N_e x K_H

N_eo = 100 kW x 1.0787 = 108 kW

Output on the dynamometer: Ne = 100 kW

Air pressure value of the test location: P = 955 hPa (955 mbar)

Air-charge temperature of the test location: t =+20 °C

Altitude of the test location: 400 m above sea level

Units: hPa = Hecto Pascal

1 hPa = 1 mbar

1 Pa = 0.01 mbar