{"id":20540,"date":"2018-12-14T16:01:35","date_gmt":"2018-12-14T16:01:35","guid":{"rendered":"http:\/\/sitepourvtc.com\/?page_id=20540"},"modified":"2023-02-15T13:08:25","modified_gmt":"2023-02-15T13:08:25","slug":"skin-friction-friction-drag","status":"publish","type":"page","link":"https:\/\/sitepourvtc.com\/nuclear-engineering\/fluid-dynamics\/what-is-drag-air-and-fluid-resistance\/skin-friction-friction-drag\/","title":{"rendered":"Skin Friction – Friction Drag"},"content":{"rendered":"
As was written, when a fluid flows over a stationary surface<\/strong>, e.g., the flat plate, the bed of a river, or the pipe wall, the fluid touching the surface is brought to rest<\/strong> by the shear stress<\/strong> at the wall. The boundary layer<\/strong><\/a> is the region in which flow adjusts from zero velocity at the wall to a maximum in the mainstream of the flow. Therefore, a moving fluid exerts tangential shear forces on the surface because of the no-slip condition<\/strong> caused by viscous effects. This type of drag force<\/strong>\u00a0depends especially on the geometry, the roughness of the solid surface (only in turbulent flow<\/a>), and the type of fluid flow<\/a>.<\/p>\n