Numerical and experimental study of inlet-outlet locations effect in horizontal storage tank of solar water heater

摘要

A good thermal stratification in the storage tank of the solar water heater is an effective process to increase the efficiency of the solar system. This study investigates numerically and experimentally the effect of varying the inlet and outlet location of the fluid in the horizontal cylindrical storage tank for optimizing the thermal stratification process. While the location of the outlet fixed, the inlet was varied and vice versa. A model based on an energy balance was introduced. Simulated temperature profile for each case was compared with the experiment, which indicated maximum deviation of up to 7%. In an experimental case at 1 p.m., the three average temperatures on the vertical line in the middle of the tank recorded 49.9, 48.7, and 48.4 °C with an average of 49 °C while the simulation result was obtained 47.1 °C. Hence, the experimental and numerical temperature difference of 1.9 °C with the error 3.9% was noticed. An appropriate location for the hot water inlet resulted in better thermal stratification in the storage tank. In addition, an appropriate location for the cold water outlet resulted a better collector efficiency, which both increased the performance of solar water heater system.