Experimental and Numerical Study of the Flow Through Helical Passage Heat Exchanger Used for Solar Air Refrigeration System

Producing compact and high effective heat exchanger system is always a challenge. These heat exchanger systems can effectively be used in many application starting from cooling electrical circuits, absorbing and storing heat from say solar ducts/panels, etc. It has been seen that the heat transfer will be more for the turbulent flows or flows where mixing dominates with higher heat transfer coefficient values. In this paper, we have developed such a small concentric annulus heat exchanger having a helical flow passage. This compact heat exchanger is utilized to replace electric heat source supplied to the Electrolux refrigerator. The helical flow is produced by providing a helical rubber baffle between the two concentric annulus pipes. Presently only one helix is studied. The flow through helical passage concentric annulus heat exchanger is simulated for various Reynolds numbers. The pressure drop, local and average heat transfer coefficient is studied and presented here. Due to the helix, the flow is very complex as well as interesting. The mushroom-shaped temperature contours are observed. At the last, the simulated results are validated with experimental values and their matching is found good.