This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Development and Use of LDV and Other Airflow Measurement Techniques as a Basis for the Improvement of Numerical Simulation of Engine Compartment Air Flows
Annotation ability available
Sector:
Language:
English
Abstract
Modern vehicles require a low aerodynamic drag to minimize fuel consumption. A not negligible share of the overall CD-value of a vehicle is produced by the engine compartment air flow. Therefore this share has also to be optimized. Furthermore, customer wishes for higher powered engines as well as for more safety and comfort result in more tightly packed engine compartments. Even the reduction of pass-by-noise required by legal reasons is often achieved with the help of underbody covers which in turn affect the engine compartment flow.
All these items may lead to rising underhood temperatures. To reduce the development time of new vehicles, numerical simulations of engine compartment air flow are more and more used to predict high temperature fields and to show ways to develop suitable remedies in the concept phase of the vehicle development. The experimental basis for such codes is provided by aerodynamic investigations in a wind tunnel. At least the three components of local velocities and the volumetric air flow at the inlet and the outlet plane have to be determined.
This paper first reports the development and the use of a modern aerodynamic “Test Radiator” for the investigation of velocity distribution and for the volumetric air flow measurements through a car cooling package. For this purpose air vanes of small diameter, able to detect even reverse flows, are used.
Furthermore, the development of various LDV-techniques, suitable for the investigation of complex flow fields, for instance behind a rotating fan are reported. And a newly developed 3-D miniature-probe is shown.
The influence of various cooling configurations, with/without condenser in front of the radiator, and with stationary/rotating puller fan and with/without vehicle speed is also shown.
Recommended Content
| Technical Paper | Cooling Inlet Aerodynamic Performance and System Resistance |
| Technical Paper | Three Dimensional Bluff Body Aerodynamic Analysis for Automotive and Automotive Racing Applications |
Authors
Topic
Citation
Berneburg, H. and Cogotti, A., "Development and Use of LDV and Other Airflow Measurement Techniques as a Basis for the Improvement of Numerical Simulation of Engine Compartment Air Flows," SAE Technical Paper 930294, 1993, https://doi.org/10.4271/930294.Also In
References
- Emmelmann H.J. Berneburg H. “Aerodynamic Drag and Engine Cooling -Conflicting Goals?” FISITA paper 905128 May 1990
- Cogotti A. “A Two-component Fibre - optic LDV System for Automotive Aerodynamics Research” SAE paper 880252 February 1988
- Cogotti A. Berneburg H. “Engine Compartment Air Flow Investigations Using a Laser-DopplerVelocimeter” SAE paper 910308 February 1991
- Bonis B. Cogotti A. Vitali D. “Numerical and Experimental Flow Field Survey of an Aerodynamically Efficient Passenger Car” ATA 1992
- Ashmawey M. et al. “A Numerical Evaluation of the Thermal Effects of the New V6 Engine on the Underhood Environment of the 1993 OPEL Vectra” Int'l SAE Congress March 1993