4827 - Comparison of SPIV Measurements for Different Test Room Air Inlet Nozzle Configurations PDF

The effect of varying inlet air velocity due to a corresponding change in inlet nozzle slot size to achieve a constant slot Reynolds number was investigated in a benchmark room. The primary objective of the project was to evaluate the dependence of turbulence intensity levels in the room upon the air inlet nozzle slot geometry. A stereoscopic particle image velocimetry (SPIV) system was used to measure airflow characteristics for two different air inlet nozzle slot sizes in an irregularly shaped test room. The inlet Reynolds number of 2,226 based on inlet nozzle slot opening was the same for the two air inlet nozzle slot configurations. The SPIV measurements were taken at five measurement locations along the center plane of the test room for both configurations. For each measurement location and air inlet nozzle configuration, a series of SPIV data were collected and averaged to determine a grid of threedimensional average velocities and normalized turbulence intensities over a 304.8 × 304.8 mm (12 × 12 in.) region. A comparison was made for the average velocities and normalized turbulence intensities at the five measurement locations for the two inlet configurations. It was found that there was a substantial shift in the center of rotation of overall airflow pattern due to a change in air inlet nozzle configuration. However, the turbulence levels in the room do not appear to be strongly dependent upon the inlet nozzle velocity because the inlet slot Reynolds number is not changed.

Units: Dual