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ISSN: 2375-3897

American Journal of Energy and Power Engineering

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A Thermal Assessment for Vertical Helical Immersion Coil Evaporator in a Water Chiller

American Journal of Energy and Power Engineering
Vol.2 , No. 5, Publication Date: Sep. 2, 2015, Page: 62-73

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Authors

[1]	Ali Hussain Tarrad, Private Consultant Engineer, Mechanical Engineering, Copenhagen, Denmark.
[2]	Fouad Alwan Saleh, Mechanical Engineering Department, College of Engineering, Al-Mustansiriya University, Baghdad, Iraq.
[3]	Deyaa M. Mahmood, Technical Training Department, Technical Institute, the Foundation of Technical Institutes, Baghdad, Iraq.

Abstract

The present investigation represents a mathematical model for the steady state thermal rating of immersed coil evaporator type. A new computation method implemented the segment-by-segment technique to simulate the shell and coil heat exchanger. The evaporator helical coil is divided according to this technique into a number of small elements to be accommodated by the surrounding shell zone. Each element and its surrounding treated as a single tube heat exchanger and modeled one by one along the refrigerant flow direction. Experimental data obtained from a water chiller of the immersed coil and shell (ICHE) type was used for the simulation process. Four different refrigerants were used for the verification of the present model namely R22, R134a, R404A and R407C for water entering temperature range of (10-21) ºC and (400) l/hr flow rate. The model predicted the experimental values of the water chiller capacity and evaporator exit water temperature within (12%) and (4%) respectively.

Keywords

Immersion Coil, Evaporator, Rating, Modeling, Heat Exchanger

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