During incident flow of bodies fluids such as air “stick” to the surface of the body and form the so-called boundary layer. The kind of flow within the boundary layer – laminar or turbulent – significantly affects the drag. The findings from studying the boundary
layer are taken into consideration when designing aeroplanes, vessels and
turbomachines. This experimental unit – used in the aerodynamics trainer FM-1849-56; allows the boundary layer on a flat plate to be studied. For this purpose, air flows along the plate, parallel to the surface. The plate has two different surfaces so as to study the effect of surface conditions on the boundary layer. Side bodies can be used in the measuring section. Thus, the boundary layer phenomena can experience interference with a degressive or progressive pressure curve and, for example equalize the friction loss of the flow.
A horizontally movable Pitot tube, adjusted using a micrometer screw, measures the total pressures at various distances from the plate surface. The plate can be moved vertically to enable the recording of total pressures in the direction of flow. The velocity can be determined from the pressures read off the tube manometers in FM-1849-56.
The experimental unit is attached to the FM-1849-56 trainer, simply and precisely with quick release fasteners.
Experiments
- Investigation of the boundary layer on the flat plate
- Influence of surface roughness on the formation of a boundary layer
- Boundary layer interference with degressive/progressive pressure curve
- Internal friction of gases
Specification
- Investigation of boundary layers on a flat plate with flow along the plate
- Accessories for the aerodynamics trainer FM-1849-56
- Plate with two different rough surfaces
- Moveable plate, along the direction of flow
- Pitot tube for measuring the total pressure at the plate
- Adjustment of the pitot tube to the plate using micrometer screw Removable side bodies for interference of the boundary layer with degressive or progressive pressure profile
- 16 tube manometers of FM-1849-56 for displaying the dynamic pressures
