Monday, October 14, 2019

Dimpling the intake ports has them picking up 8% more flow and and 5% more velocity


That's why golf balls are dimpled, and why Nascar outlawed dimpling the hoods, roofs, and trunks of race cars

https://beautifullyengineered.tumblr.com/post/116131933473/ls3-intake-port-with-kelford-cams-dimple

8 comments:

  1. so why dont they dimple the skin of airplanes?

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    1. airplanes probably use the skin as the stress bearing material that would possibly fail with dimples, as the forces on the skinf durin take oo and landing, and emergency banking, dive and pull up, etc might fail with the dimples

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    2. There are two types of drag; base drag and skin friction drag. Base drag is the drag created when airflow separates from a body creating a low pressure area behind the body. Skin friction drag is the drag generated by airflow rubbing against the body. Golf balls take advantage of dimples to create small vortices that energize the flow, which keep it attached to the body longer. This energized flow creates more skin friction drag, but reduces base drag. In the case of a round body, like a golf ball, the base drag is so much bigger than the skin friction drag, that even though the dimples increased the friction drag, they reduced the base drag so much that the net effect is a reduction in total drag.

      Airplanes use much more streamlined shapes, so they already have really low base drag. If airplanes use dimples to energize flow, they will increase skin friction drag, but won't gain much in terms of their already low base drag. So the net effect will be an increase in total drag. (Unless your airplane is shaped like a ball).

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  2. Rough surfaces for airplanes are common and very effective by the way.

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  3. Cars looking like golf balls will be interesting

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  4. ... also ships use this technology on their friction with water, fluid dynamics

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  5. I would think a big trucking firm would be all over this.

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  6. I'm just going back to old school when the train of thought was port and polish. Who knew?

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