Experimental Study on Heat Transfer Characteristics and Pressure Drops for Water Flowing in Spiral Coil Heat Exchanger

Abstract

The heat transfer and pressure drop characteristics for water flowing in four spiral coils with different shapes and different sizes were experimental studied. Reynolds number range from 4000 to 9000, volume flow rate range from 200 to 350 L/h and heating power range from 80-350 W. Based on the experimental results, the regularity of Reynolds number and heating power influencing on heat transfer and pressure drop characteristics was analyzed and discussed. The results indicate: the Nu increases with increasing Re, the greatest average heat transfer coefficient appears in the smaller circular spiral coil. The heat transfer coefficients increase with increasing heating power, the greatest average heat transfer coefficient also appears in the smaller circular spiral coil. The pressure drops increase with increasing Re, the pressure drop in big ellipse spiral coil is greatest. The resistance coefficients gradually decrease with increasing Re. The resistance coefficient of small circular spiral coil is always greatest, and the resistance coefficient of big circular spiral coil is smallest.

Numerical investigation of heat transfer characteristic of fixed planar elastic tube bundles

“…Helical coil heat exchanger with electric heating system was investigated in experimental stage. Details of schematic diagram of the experimental apparatus can be found in their research [22]. They presented the experimental correlation of circular tube-side turbulent convective heat transfer in the helical coil heat exchanger as follows,…”