An Experimental of Enhancement Heat Exchanger (Shell And Coil) by Different Types of Soil

Abstract

Abstract Soil is one of the sources of energy conservation, accordingly, the present work aims to enhance the thermal storage efficiency and the thermal behavior for a heater system integrated with a helical coil cylindrical system. The helical coil, combined with a tank having a cylindrical shape, has a diameter of (250) mm and a height of (600) mm, placed under the electric heater. In the experimental study, latent heat storage materials (soil, sand and their mixture) having a high specific heat were used to raise the thermal storage. Different cases under a constant temperature hot water (80 0C) from an electric heater with 100 W/m2 were considered. In the first case, the helical coil was immersed in pure sand in the cylindrical tank, and in second case, the helical coil was immersed in compound (50% sand and 50% soil) in the cylindrical tank, while in third case, the helical coil was immersed in pure soil in the cylindrical tank. These cases were verified for both natural and forced convection with different mass flow rates (0.008 and 0.016 kg/sec). For the forced convection with (0.008 kg/sec), the results indicated that the compound (sand and soil) compared with pure sand gave the best thermal storage duration by approximately (36.84%). There was an increase in the outlet water temperature by (8%), and an increase in the mass flow rate to (0.016 kg/min). The duration was (37%), with an increase of (5.84%) in temperature. The increase of the rate of mass flow led to a reduction in time of the outlet water temperature of discharge process.