Investigation of Heat Transfer Rate of Thermosiphon Pipe for Low Temperature Application

Abstract

This research aims to study towards the heat transfer rate of Thermosiphon t pipe for low temperatureapplication. Copper is being used as the material to make the straight shape of the pipe which being appliedto be used in the heat emission system at the low temperature as to figure out the functional work fluid and theappropriateness in the quantity of the work fluid to be used in the installation of the Thermosiphon pipe bystudying 1) the types of functional work fluid at R-12, R-22, R-134a, R-404a, and R-406a , respectively, and 2)the quantity of proper work fluid at 20, 40, 60, and 80 percent of heat pipe capacity respectively by using hotwater to inject the heat for the pipe. In the part of the evaporator section, the heat of hot water was changed at40, 50, 60, 70, and 80 degrees Celsius, respectively.From the experiment, it was found that work fluid R-404a at 20 percent of the capacities of the heatpipe was best for heat emission at the heat transfer rate approximately about 2.1 watt / minute, the next workfluid to be used was the R-134a at 60 percent of the capacities of heat pipe, and the third work fluid to beused was R-406a at 80 percent of the capacities. When the building budget was limited, the use of the heatpipe is considered another reasonable application to be used for decreasing the heat from the walls of thebuilding. The budget used for producing the Thermosiphon pipe was relatively reasonable at approximatelyat 119 Baht/meter Thermosiphon pipe.