The subject of this paper is the experimental determination of the flow characteristics of three-dimensional wall jets. The jets were produced from a diffuser with a rectangular outlet. The diffuser outlet size and flow rate were varied to produce both low and high outlet aspect ratios and Reynolds numbers. Velocity profile measurements were made to determine the centerline velocity decay and the extent of the lateral and vertical spread of the jet.
Thermal anemometers with omnidirectional sensors are recommended in the standards to be used for low-velocity measurements indoors. Requirements for the directional sensitivity of the velocity sensor are prescribed. However, a method for testing the directional sensitivity of low-velocity anemometers does not exist. A simple test procedure is used in practice to identify the so-called "yaw" and "roll" directional sensitivity of an omnidirectional velocity sensor.
The two-dimensional, transient numerical model of heat and water vapor convection and diffusion during air exfiltration within fiberglass insulation, presented in Part /, is validated in Part II, with experimental data for temperature, moisture and frost accumulation, and heat flux. With a few exceptions, the simulation results and experimental data agree within the experimental uncertainty. Exfiltration airflow in the two-dimensional space showed strong entrance and exit effects for temperature, moisture and frost accumulation, and heat flux on the cold side.
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