Boundary layer(边界层) Although frictional effects in slightly viscous fluid are indeed present, they are confined to a thin layer near the surface of the body, and the rest of the flow can be considered inviscid (1904 PrandtL) 第三届国际数学大会 德国海登堡 (论性很小的流体运动) Ludwig Prandtl(1875-1953)3 Boundary layer (边界层) Although frictional effects in slightly viscous fluid are indeed present, they are confined to a thin layer near the surface of the body, and the rest of the flow can be considered inviscid. (1904, Prandtl) Ludwig Prandtl(1875-1953) 第三届国际数学大会 德国海登堡 （论粘性很小的流体运动）