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Peter7307 · 08-19-2011, 10:38 AM

[QUOTE=mort;256699]Hi lunarhighway,
Before 1974 there were no full size automotive wind tunnels. Before then and still today published drag figures for real cars are derived from coast down tests. The drag numbers should be exactly comparable. Some prototype work publishes drag numbers based on wind tunnel tests on models.
-mort[/Q

Sorry but not so.

The St Cyr wind tunnel in Paris was in use in the 1920's and is still used today especially by Citroen and Peugeot.

Coast down tests are probably still used by some makers but most have moved on the CFD and wind tunnel data.

German universities also had auto wind tunnels in the 1930's to help with the aero work on the Audi and Mercedes cars of the mid and late 1930's (usually referred to as Silver Arrows)

Peter.

08-19-2011, 10:38 AM	#16 (permalink)
Peter7307 Master EcoModder Join Date: Jan 2008 Location: Victoria , Australia. Posts: 499 Thanks: 20 Thanked 46 Times in 33 Posts	[QUOTE=mort;256699]Hi lunarhighway, Before 1974 there were no full size automotive wind tunnels. Before then and still today published drag figures for real cars are derived from coast down tests. The drag numbers should be exactly comparable. Some prototype work publishes drag numbers based on wind tunnel tests on models. -mort[/Q Sorry but not so. The St Cyr wind tunnel in Paris was in use in the 1920's and is still used today especially by Citroen and Peugeot. Coast down tests are probably still used by some makers but most have moved on the CFD and wind tunnel data. German universities also had auto wind tunnels in the 1930's to help with the aero work on the Audi and Mercedes cars of the mid and late 1930's (usually referred to as Silver Arrows) Peter.