Experimental and Numerical Investigation of Flash Evaporation in a Wickless Heat Pipe With a Jet Nozzle for Thermal Distillation Applications

ABSTRACT The impact of flash evaporation on the thermal performance of a wickless heat pipe utilized in desalination applications is examined experimentally and numerically in this study. Injecting water through a jet nozzle into a wickless heat pipe at high temperatures (between 373 and 393 K) causes it to become superheated. Using a jet nozzle with a small diameter (0.4 mm), the rapid evaporation process was started. The study looks at the main factors that affect how effective quick evaporation is, such as the cooling water flow rate, the input temperature, and the feeding water's mass flow rate. A constant liquid mass flow rate of 0.00138 kg/s was used for the experiments. The two‐phase flow and related heat transfer processes, such as evaporation, condensation, and phase change events, inside the straight heat pipe were modeled using computational fluid dynamics simulations. To more accurately reflect these intricate interactions, a nonhomogeneous multistage model was employed. The findings demonstrate that raising the liquid's inlet temperature increases the production of steam by excessive evaporation, which raises the condensate flow rate. It was found that the condenser's maximum output happened at 388 K. Higher condensate flow rates and inlet temperatures also increased the evaporation efficiency, which peaked at 86% at 393 K. The effectiveness of the thermal system and the validity of the numerical model were confirmed by the good connection between the experimental data and the temperature models predicted by computational thermodynamics.