A systematic study of the influence of process variables on the overall heat transfer coefficient in a shell and tube heat exchanger

  • Naveed ul Hasan Syed Department of Chemical Engineering, University of Engineering and Technology Peshawar, Pakistan
  • Qurat-ul- Ain Department of Chemical Engineering, University of Engineering and Technology Peshawar, Pakistan
  • Muddasar Habib Department of Chemical Engineering, University of Engineering and Technology Peshawar, Pakistan
  • Naseer Ahmed Khan Department of Chemical Engineering, University of Engineering and Technology Peshawar, Pakistan
  • Sultan Ali Department of Chemical Engineering, University of Engineering and Technology Peshawar, Pakistan
Keywords: Energy conservation, Heat flux, Modeling, Segmental baffles, Thermal boundary layer

Abstract

A systematic experimental study was carried out on a shell and tube heat exchanger (STHx) to examine the influence of process variables such as hot and cold water flow rate, and the hot water inlet temperature on the overall heat transfer coefficient (U). The results show that the U increased with increasing the hot water and cold water flow rates. Similarly, the increase in hot water inlet temperature, improved heat transfer rate. It was observed that the increase in the U by increasing the cold water flow rate was significantly higher than with increasing the hot water flow rate. Under similar process conditions, at 36 oC hot water inlet temperature, the U increased from 709.96 to 1045.50 W/(m2.oC) with the increasing cold water flow rate from 0.75 to 2.5 L/min. While for the hot water case, the U increased from 709.96 to 940.43 W/(m2.oC) for the corresponding hot water flow rate. An empirical model correlating the outlet temperature of the STHx fluids with the inlet conditions has also been proposed. The proposed model was used to calculate the outlet temperatures of the hot and cold water and the heat flux. The model predictions were compared with the experimental results and a good agreement was found.

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Published
2018-12-31
How to Cite
Syed, N. ul H., Ain, Q.- ul-, Habib, M., Khan, N. A., & Ali, S. (2018, December 31). A systematic study of the influence of process variables on the overall heat transfer coefficient in a shell and tube heat exchanger. JOURNAL OF ENGINEERING AND APPLIED SCIENCES, 37(2), 53-60. https://doi.org/https://doi.org/10.25211/jeas.v37i2.2895