Vehicle road load which must be simulated on a chassis dynamometer for exhaust emission and fuel economy tests is usually determined by on-road coastdown tests. In this study, we divided vehicle road load into rolling resistance and aerodynamic drag, and measured these forces in laboratory tests, using a high-precision chassis dynamometer and a full scale wind tunnel. However two problems arise. One of tham is that tire loss measured on the curved drum of a chassis dynamometer is larger than on the road. Another is that aerodynamic drag measured in a closed-throat wind tunnel, which has blockage effects, is larger than on the road. To determine vehicle road load from laboratory tests, we therefore have to establish how to obtain a correction coefficient for tire loss between the actual road and the drum, and a correction coefficient for aerodynamic drag between the actual road and a wind tunnel. How we get these coefficients is described in this paper. (Wassmann)
A new approach to measuring road load by chassis dynamometer and wind tunnel tests
Ein neues Verfahren zur Messung der Strassenbelastung durch Fahrgestelldynamometer- und Windkanalversuche
SAE-Papers ; 1-9
1982
9 Seiten, 9 Bilder, 11 Tabellen
Aufsatz (Konferenz)
Englisch
A New Approach to Measuring Road Load by Chassis Dynamometer and Wind Tunnel Tests
SAE Technical Papers | 1982
|A New Approach to Measuring Road Load by Chassis Dynamometer and Wind Tunnel Tests
Kraftfahrwesen | 1982
|Road rating with chassis dynamometer
Engineering Index Backfile | 1956
|Road rating with chassis dynamometer
Engineering Index Backfile | 1955
|Chassis Dynamometer Simulation of Road Load Using Coastdown Techniques
SAE Technical Papers | 2014