Measurement of velocity distribution and turbulence in a special wind tunnel using a laser Doppler velocimeter
Abstract
The flow behavior in a jet mixing visualization chamber for turbulent fuel spray mixing with air under compression, e.g., at top dead center in diesel engines, was investigated with a laser Doppler velocimeter. The measurements were performed in two cuts in the profile perpendicular to the flow direction. The range of flow conditions in the measuring chamber was tested. The measurements were conducted with and without turbulence grids and shear flow grids behind the inlet nozzle. Wire grids did not enhance the turbulence in the measuring chamber. One of the tested shear flow grids produced shear flow as expected. A turbulence grid whose design was based on experimental results, produced a turbulence degree of up to 30% over the whole measuring cross section.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- June 1981
- Bibcode:
- 1981STIN...8222466M
- Keywords:
-
- Diesel Engines;
- Flow Characteristics;
- Jet Mixing Flow;
- Shear Flow;
- Turbulent Flow;
- Data Reduction;
- Flow Visualization;
- Laser Doppler Velocimeters;
- Turbulent Mixing;
- Velocity Distribution;
- Fluid Mechanics and Heat Transfer