Heat Transfer Visualization of the Application of a Cooling Pipe in Sand with Flowing Pore Water.

The authors introduce an experimental method that focuses on the flowthermal relation and the visual observation of heat distribution around a cooling pipe in sand under the flow condition. This experiment aims to understand the effect of seepage flow on the heat transfer behavior of sand under cooling and freezing conditions due to a vertically buried heat exchanger pipe. This method combines a flow test, cooling or freezing processes, and the visual observations of temperature profiles with saturated Toyoura sand as the heat transfer medium. Avertical copper pipe inserted into the sand medium is used as the thermal exchanger, while an infrared thermograph is used to measure and visualize the surface-temperature profile of the specimen. The heat transfer distribution behavior is investigated by conducting a series of cooling and freezing experiments on the specimens with variation of the flow rate condition, initial condition, and pipe depth. The thermograph observation results show how water flow obviously affects the shape and intensity of the heat distribution. [ABSTRACT FROM AUTHOR]