The energy storage ability and temperature arrangement of a concrete bed which was charged and discharged at the same time was examined mathematically in this research. This was carried out by modeling a single globe-shaped concrete which was utilized to simulate a series of points along the concrete bed axis. Charging and discharging mode of the system were compared for 0.0094, 0.013, and 0.019 m3/s air flow rates. Higher change in temperature response was detected between the charging and fluid to solid heat transfer process at the inception of the concrete bed and the heat gain by the cool air flowing inside the copper tube was fairly high. The analysis of energy storage efficiency was also carried out and it was noticed that the globe-shaped concrete of 0.11 m diameter has the highest storage efficiency of 60.5% at 0.013 m3/s airflow rate.
Part of the book: HVAC System
Thermoelectric devices use the Peltier effect that creates a heat flux between the junctions of two different types of materials. The thermoelectric module also referred to as a heat pump transfers heat from one side to the other when a DC current is applied. This study carried out the theoretical analysis of a thermoelectric air conditioning system. A prototype thermoelectric air conditioner of 286 W cooling capacity was built and a testing enclosure made from plywood and Styrofoam was also constructed in order to validate the theoretical result with an experimentation. It was discovered that thermoelectric air conditioning took 4 minutes to reach its desired temperature of 22°C, whereas the standard air conditioning system (refrigeration cycle) took 20 minutes to cool to a room temperature. Economically, it was also discovered that thermoelectric air conditioning system is 50% cheaper than the refrigeration cycle air conditioning systems. The thermoelectric air conditioner has cheaper maintenance and greater estimated life span of 7 years more than the refrigeration air conditioner. This is because the air conditioner that operates on the refrigeration cycle uses a rotating compressor, while the thermoelectric air conditioner uses thermometric module.
Part of the book: Low-temperature Technologies