Transient heat transfer measurements for planar and circular wall jet using liquid crystal thermography

The objective of this study is to compare the fluid flow and the heat transfer characteristics between a 2-D planar and a 3-D circular wall jet along the stream wise direction. The experiments are performed at a Reynolds number of 5540 for nondimensional streamwise distance ranging from 0 to 40. The hot wire anemometer is used to quantify the velocity distribution on the jet spread and the local maximum velocity decay along the stream wise direction. Liquid Crystal Thermography (LCT) technique is used to map the surface temperature and the semi-infinite approximation methodology is used for extracting the heat transfer coefficient. From the results it is observed that, the 2-D planar wall jet shows lesser distribution of RMS values in the near field and better heat transfer performance than that of the 3-D circular wall jet.