Practical Study to Improvement the Performance of Heat Exchanger Using Passive Techniques

Abstract

The aim of this study to improve the performance of heat exchanger by using the medium integral fins on the cross flow heat exchanger practically, so, two the heat exchangers from copper were manufactures with eight passes for comparison under different boundary conditions. The water flow rate flow inner the tubes with (2, 3, 4, 5, 6) L/min with inlet temperatures (50, 60, 70) oC, as for the air flow rate were passed outer the tubes by speeds (1, 1.7, 2.3) m/sec. The results show that the medium integral finned tube gives more improvement the heat transfer than the smooth tube about 203.97% and 205.1% was enhancement factor. Motivation: The aim is improvement the heat transfer coefficient for cross flow heat exchanger by using medium integral finned tube. Study the effect of various water stream rate, air speed and inlet water temperature on heat transfer coefficient for them, Finding the cases which enhanced heat transfer for various ranges of air and water as well as inlet temperatures and the speed at the entrance. Develop the empirical correlations for (Nua) of smooth and medium integral finned tubes as function of (Pra) and (Rea).

Enhancement Thermal Transmission for Cross Flow Heat Exchanger by Using Triangular Fins Experimentally

“…PVC pipes insulated by Polyurethane foam insulator. Figure (5) shows the test section. Electrical AC motor drive centrifugal water pump, with head of pump (24m), electric power (370W) and flow rate (30L/min).…”

“…The rate of heats transfers of finned tubes increases when the Reynolds number is increases. Taher and Kadhim [5] investigate practically the enhancement of heats transfers coefficient of cross-flow heat exchanger using medium fins. Using different water flow rate ("2, 3, 4, 5, 6") L/min, air velocity ("1, 1.7, 2.3") m/sec and inlet water temperature ("50, 60, 70 °C").…”