Fluid mechanics is concerned with the physical behaviour of fluids. An important branch of fluid mechanics is the analysis of air flow in the incompressible range in order to be able to determine the pressure distribution and the velocity profile of a flow. In practice, the findings from these experiments are necessary when devising and designing turbomachines.

With its extensive range of accessories, the HM 220 unit offers a variety of experiments in the field of steady, incompressible flow. The external Pitot tube is used to measure free jets; the inner Pitot tube allows investigation of the air flow within the pipe section. A low-loss inlet and the length of the pipe section realize an optimal formation of the air flow. The air flow can optionally be studied via a nozzle or orifice plate. An iris diaphragm allows the diameter of the air flow to be varied. Pipe friction losses on various pipe fittings can be investigated. Up to 20 pressure measuring points mean the pressure conditions along the measuring section can be determined. The pressures that are read off the tube manometer make it possible to determine the pressure distribution and flow velocity.

In addition to the extensive accessories supplied, there is the optional Venturi tube HM 220.01 for practical verification of the continuity equation and the conservation of energy during a change in cross-section of the air jet.

As an additional optional accessory, HM 220.02 offers boundary layer
measurements on a flat surface in longitudinal flow. The experiment results are used to determine velocity distributions within the boundary layer and to represent the boundary layer thickness.