Test for heat transfer performance of a plate heat exchanger

Abstract

The objectives of the present study are to find a suitable heat transfer correlation for a pilot-scale plate exchanger and to develop a computer program to aid in the design of plate heat exchangers using the correlation obtained. The pilot-scale plate heat exchanger studied has a plate sap of 0.00313 m, a width of 0.1125 m., a length of 0.445 m, it has chevron corrugations (angle = 50 degrees), and a surface area of 0.05 m2. The exchanger tested has three sections. The range of products tested includes water, syrup (sucrose solution of 20 wt%, 30 wt% and 40 wt% concentration), and glycerine (glycerine in water at 40 vol%, 50vol% and 60 vol% concentration). Their flow rates were varied to yield Reynolds numbers ranging from 100 to 4,000. The Prandtl numbers of the products ranged from 2.11 to 40. One of the heat transfer correlations for the tested plate heat exchanger is Nu = 0.2 0 Re0.87 Pr0.78 The proposed correlation is found to correlate the experimental data resonably well with a standard deviation of 0.081. To aid in the design of plate heat exchangers a computer program has been developed, using the obtained correlation and incorporating the physical properties of all the tested liquids. The program is coded in TURBO BASIC and uses the effectiveness-NTU approach design procedure. The design and calculation results of the program are found to agree well with experimental results as well as with actual HTST processes.