 Missile inlet in the VMK vertical free jet test section. |
Design and components of the VMK vertical free jet test section. |
Operating area of the VMK vertical free jet test section. |
Description
VMK is a “blow-down” wind tunnel with a vertical free jet test section for the simulation of the flow in the Mach number range from 0.5 to 3.2. In this facility, the air flows via a total pressure control valve to a contoured axial-symmetrical nozzle. Downstream the nozzle it enters the test section. It has a concrete tower with overpressure protection, in which the model is either mounted on an angle of attack adjustment device or a special support, depending on the application.
The design and the size of the test chamber enable tests with solid propolents and/or with hydrogen combustion. By means of its heater capacity for total temperatures up to 700 K VMK allows to simulate sea level flight conditions up to a Mach number of 2.8 with a correct duplication of the corresponding pressure and temperature. On average, up to 10 tests a day are carried out at this facility, with a typical run time of approx. 60 seconds.
Application areas
- Simulation of aerothermodynamic loads on missile components during flight at sea level conditions.
- Investigation of nozzle flows and/or control of missiles via solid propellants or hydrogen combustion.
- Measurements on ram engines.
- External combustion with hydrogen.
Measurement techniques
- Flow visualisation with Schlieren optics and oil flow methods.
- Schlieren optics and oil flow method (up to 150 kHz).
- Steady and unsteady pressure distribution measurements.
- Temperature and heat flux measurements with thermocouples and infrared technology.