Print

Fuel Consumption Measurement for Diesel Engines.

KRAL flowmeters are the basis for maximum system precision.

A complete system from one source.
The benefit of the screw spindle principle is its insensitivity to vibration. There is no loss of precision.

High precision flowmeters.
Thanks to their high measurement precision of ±0.1%, KRAL flowmeter ensure system measurement precision of as high as ±0.4% at full load. The system precision increases with the circulation rate.

Measurement independent of direction.
To detect the direction of flow, an additional flow direction sensor is required besides the flow sensor. A correct consumption value is only possible in this way.

Measurement of mass.
The KRAL BEM 500 electronic unit can read in the measured values from temperature sensors. With density conversion, the KRAL flowmeter becomes a mass flow measuring system.

Measurement with pressure pulsation.
Injection pumps cause pressure pulses in low pressure fuel lines, resulting in short term changes of the fuel’s direction of flow. KRAL flowmeter in principle measure in both flow directions. Reverse flows are detected correctly and taken into account in the formation of measured values. The result is a very precise, variance-corrected measured value.

High system precision.

Measurement errors in differential measurement.
Idling Full load              
Single flow
measurement
SystemSingle flow
measurement
System
0.1 % 2.2 %0.1 %0.4 %
0.3 % 6.2 %0.3 %1.0 %
0.5 % 10.3 %0.5 %1.8 %
1.0 % 20.5 %1.0 %3.6 %
3.0 % 61.0 %3.0 %10.8 %
 

Where one measured value is calculated from several individual measured values, the error of the individual measurements is propagated according to the Gaussian error propagation law. The table shows the measurement errors of a system depending on the precision of the individual meters. The table values are calculated according to the error propagation law for two engine states: „idling“ and „full load“.

The calculated results show that the system error, for mathematical reasons, rises sharply even at a slight deterioration of the precision of the individual meters. Flowmeters with a measurement precision of 0.5 % and up are unsuitable for consumption measurements on engines which may be idled. A 10.3 % system error is not worth spending money on. In contrast, KRAL flowmeters, because of their high measurement precision of 0.1 %, achieve optimum system measurement precision for both idle and full load.

KRAL Volumeter® - Precise flowmeters.

With a measurement precision of ±0.1%, reproducibility of 0.01%
and a measurement range of up to 100:1, calibration and testing institutes assess KRAL flowmeters as the most precise displacement meters for industrial applications. The KRAL flowmeter measures independently of the direction of flow. These unique properties mean that the KRAL flowmeter is ideal for fuel consumption measurement. Some system suppliers describe only their electronic system, without giving information about flowmeters. We at KRAL are convinced that precise meters are important, because they provide the input for the electronic system.

Single line measurement and differential measurement.

The measurement precision of fuel consumption measurement is determined by the number of flowmeters used. Where only one flowmeter per engine is required, the high precision of the KRAL flowmeter can be fully exploited. Where two flowmeters are required, system measurement precision is reduced according to Gaussian error propagation. One KRAL flowmeter will be sufficient if the fuel supply behind the tank branches into a ring line. Two flowmeters will be required if the return line leads directly into the tank, or each engine of a multi-engine system is measured.

 


The KRAL fuel consumption measurement in the industries.

 

Oil & Gas

The right fuel balance in multi-engine systems.
To ensure low fuel consumption, the diesel engines have to run at their optimum operating point...
Read more >>

 
 
 

 

Marine

 
 
 

 

Power Generation

Fuel consumption measurement for diesel engines.
KRAL fuel consumption measurement takes into account the effects of the engine system and...
Read more >>

Fuel consumption measurement for turbines.
It is now possible to measure fuel consumption precisely and reliably, directly in the fuel line...
Read more >>

 
 
 

 

Mechanical Engineering

 
 
 
 

KRAL - USA, Inc. | P.O. Box 2990 | Matthews NC 28106 | 901A Matthews-Mint Hill Road | Matthews NC 28105 | USA