SANDEEP REDDY LEKKALA

PALASH DESERT AIR COOLER

Abstract

This paper presents performance analysis of two new evaporative cooling pad materials. Now-a-days evaporative cooling pads are commonly made from regular pads (aspen and khus fibers). These two materials along with new materials namely coconut fibers and palash fibers have been tested in a laboratory using suitably fabricated test set up. Air flow rate was kept constant. Evaporative cooling effectiveness was obtained and compared with that of regular pads (aspen and khus fibers).. The effectiveness of pad with palash fibers was found to be 13.2% and 26.31% more than that of regular pads(aspen and khus fibers) respectively.

Introduction

 India is a tropical country in which most of the regions experience very low temperatures during the winter and very high temperatures during the summer seasons. That is, the temperature range between summer and winter seasons is very large. Hence, it is not a very pleasant experience and highly uncomfortable. Though cheaper methods of heating are available during the winter season, methods of cooling down the hot temperatures during the summer do not have wide variety of options. Air conditioners have high initial and running costs, which cannot be afforded by all the people in a developing country like India. Air coolers are relatively cheap, but provide unsatisfactory results; there is a need for developing a cheaper room cooling system.

Idea

 Testing results after analysis would determine the best material with respect to performance .Literature reveals the manufacturing of conventional desert coolers expecting a single entry for a modern desert cooler. The experiment results obtained so far after analysis would suffice parametric conditions for a modern desert cooler. This natural evaporative cooling is otherwise known as perspiration which secrets from body to cool itself. The heat transfer from the body depends on the water evaporation rate of water. This rate of evaporation of water purely depends on the temperature humidity of the air as well as the pressure of the particular place. Hence, sweat accumulates more on hot humid days in which the perspiration is impossible to evaporate.

Experimental test set up was developed and fabricated as shown below to determine the saturation effectiveness of cooling pads.

The set up includes a tunnel, a blower, rigid pad media, a recirculating

pump, a sprinkler and a water collecting tank.

A connecting piece of rectangular cross section connects the test section to the blower

whereas other end of the test section connects the diffuser. Ambient

air was forced to circulate through the tunnel by blower. Cooling

water was sprayed from above the test section by sprinkler onto

the top surface of cooling pad. The falling water was collected in

the water collecting tank and was re-circulated through the pump.

A provision was made for easy changing of cooling pad of different

materials and thicknesses.