A Standard Method for Measuring Fuel System Pulse Damper Attenuation

Fuel injection systems are pressurized to 100 kPa and higher. As injection pressures increase there is also an increase in the potential for flow induced pressure pulsations. Fuel flow instabilities, especially at cold temperatures, can adversely affect driveability. Issues of noise and driveability caused by fuel flow ripple in fuel injection systems can be resolved by using the correct pulse damper. For comparing pulse dampers and for calibration purposes, it is important that standard methods are used to measure performance.

This paper presents a standard method for measuring fuel system pulse damper attenuation at low frequencies. The paper presents fundamental acoustic considerations, reviews the performance required for pulse dampers in fuel systems, reveals a standard test method, shows attenuation data obtained with the standard procedure and analyzes the test results.

The data includes repeatability and damper population performance information. An insertion loss based procedure is shown to provide better discrimination than a classical transmission loss approach. Recommendations are made for extending the test frequency range and enhancing the procedure.