An experiment to evaluate the thermal performance of an oil-heating copper spiral coil

An experimental setup to evaluate the thermal performance of an oil-heating copper spiral coil heat exchanger is presented. The thermal performance is evaluated in terms of energy and exergy analyses. Results obtained while increasing the flow-rate of the fluid through the coil show an increased heat transfer rate, resulting in a reduction in the temperature difference between the outlet and inlet temperatures of the coil. An increase in the flow-rate is found to increase the rate of heat gained by the oil for a limited range of the flow-rate since heat losses are also increased. The average rate of heat gained by the oil is found to be around 350 W, while the average thermal efficiency of the coil is found to be around 0.25. The rate of exergy delivery and exergy factor results show that lower flow-rates result in a greater rate for the exergy delivered to the oil during the initial stages of the experiments. The heat loss factor is found to increase with an increase in the flow-rate. Due to the simplicity of the experimental setup, it can be used to introduce experimentally the concepts of energetic and exergetic performance of a thermal process or device to senior undergraduate students taking courses in applied thermal physics or applied thermodynamics.