Heat transfer analysis of a water/lithium-bromide vapor generator system used for battery thermal development

Abstract

In this study a heat transfer analysis of water/lithium-bromide generator or desorber is performed based on a numerical technique to develop a battery performance. The considered generator is a battery as a shell and tube type heat exchanger with rectangular cross section where a hot water streams inside the tube side of the heat exchanger from left to right, while the Li–Br solution flushes uniformly from the top of the generator towards the shell side of the heat exchanger which contains pool of the solution which bathes the heat exchanger tubes. Thermal parameters of the generator such as temperature and concentration distribution of the streaming Li–Br solution in the shell side of the generator, as well as temperature profile of the heating hot water streaming inside the tube banks are presented in this study. The exit parameters of the generator such as mass flow rate, concentration and temperature of the strong solution leaving the generator as well as temperature and mass flow rate of the generated vapor skipping the generator are computed. The exit parameters of the heat exchanger are compared against EES (Engineering Equation Solver) software result. It found that the numerical result of this study is close to EES result. Moreover, the effect of inlet temperature of the hot water to generation of vapor is investigated and it is found that as the inlet temperature of the hot water decreases, the generated mass flow rate from the desorber decreases.