Determination of mean and dynamic skin friction, separation and transition in low-speed flow with a thin-film heated element

摘要: The application of a heated thin metallic film to the measurement mean skin friction in laminar and turbulent flow on flat plate, circular cylinder an annular tunnel is described. manner which transition separation are detected with this instrument illustrated by reference tests cylinder. influence ambient air temperature gauge behaviour analysed it shown that reliable element can be constructed, capable being moved from one location another, while retaining its calibration. An element, calibrated oscillating used obtain spectral density boundary layer.