Thermal Diffusion Phenomena in Vertical Free Jet Using Two-Dimensional Channel Counterflow
Shuichi Torii
A numerical analysis is performed to investigate thermal diffusion phenomenon in vertical free jet using the counterflow formed with the two-dimensional channel, in which the hot-fluid jet is injected from the inner channel and the surrounding fluid is sucked in the outer channel. Emphasis is placed on the effects of suction flow rate and Reynolds number on thermal diffusion. It is found that (i) the flow pattern and isotherms in a laminar jet are affected by the velocity ratio of the injection to suction fluids and the Reynolds number, (ii) the thermal diffusion is amplified with an increase in the Reynolds number, and (iii) as the velocity ratio is increased, the streamwise velocity gradient near the nozzle tip is intensified, resulting in an amplification in the thermal diffusion in the downstream region.