This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Analysis of Flow Phenomena on an Acoustic Roller Dynamometer in Order to Analyze the Flow Through the Engine Compartment and on the Underbody for Thermal Applications
Technical Paper
2007-04-0057
Sector:
Language:
English
Abstract
Testing times in climatic wind tunnels are rare and expensive.
In the development process of vehicles virtual testing and road
tests are essential to reduce development costs. MAGNA STEYR runs a
four-wheel-drive acoustic roller dynamometer with wind simulation
up to 135 km/h which could also be used for thermal testing.
It is definitely not the goal to have the right cp
distribution on the upper side of the vehicle or the right drag
coefficient as this would not be possible with the dimensions of
the same as in a climatic wind tunnel. For thermal applications
especially the flow towards the radiator, through the engine
compartment and on the underbody (up to the B-column) are of
special interest.
The current work focuses on the differences in the flow when
looking on the roller dynamometer compared to an climatic wind
tunnel and road tests focusing on the flow towards the radiator,
through the engine compartment and on the underbody (up to
B-column).
The differences are shown on a thermal model of a full vehicle.
This model is run under typical testing conditions (e.g., 35 km/h
hill with trailer). To perform these simulations a conventional CFD
is used. Three environmental testing conditions are simulated and
compared to each other. These are the acoustic roller dynamometer,
the climatic wind tunnel and the road simulation. The aim is to
show whether the acoustic roller dynamometer can be used for
thermal investigations and where the limits of the wind simulation
are.