EFFECT OF ORIENTATION OF SHELL AND TUBE LATENT HEAT STORAGE UNIT ON MELTING PHENOMENA OF PHASE CHANGE MATERIAL
Solar thermal energy is very vital in applications such as solar water heating, solar air heating, solar dryer etc. But due to unpredictable nature of solar energy, effective utilization of solar energy remains unsuccessful. Compared to other techniques of energy storage, latent heat storage is an efficient way to store solar thermal energy using different Phase Change Materials (PCMs). This is because of its features such as high storage density, constant operating temperatures during phase alteration. From the literature, it was found that during melting of PCM, natural convection heat transfer is dominant. Natural convection heat transfer depends on the orientation of the test section. The objective of the present paper is to numerically establish thermal performance of PCM filled in vertical, horizontal and inclined (45°) shell and tube type LHSU. Simulations are carried out using enthalpy porosity approach. A 2-D slice of LHSU is modeled in order to reduce the computational time. After validation, the effect of orientation of test unit on melting process is analyzed numerically. Effect of orientation on total melting time is analyzed to identify the best suited orientation of the test unit. The effect of fluid inlet temperature on the thermal performance of LHSU is also established. It is found that inclined shell and tube configuration takes less time for melting of PCM. It is also noted that effect of HTF temperature is significant toward reducing the melting time.