Boundary Layers Teaching Equipment Fluids Mechanics Lab Equipment

SR225.02 Boundary Layers Teaching Equipment Fluids Mechanics Lab Equipment

1.Description

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.

The experimental unit – used in the aerodynamics trainer – 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 equalise 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.

The experimental unit is attached to the trainer, simply and precisely with quick release fasteners.

2.Technical details

Specification

investigation of boundary layers on a flat plate with flow along the plate

accessories for the aerodynamics trainer

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 for displaying the dynamic pressures

Technical data

Pitot tube

diameter: 0,7mm

movable: 0,35…50mm

Plate, movable: 0…250mm

LxW: 260x55mm, thickness: 5mm

chamfer: 30°

smooth surface: 25µm

rough surface: 400µm

2 side bodies, removable

inclination: 1:12,5