الفهرس 
Heat Exchangers OvervieOnly 14 pages are availabe for public view
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Abstract
Heat exchangers used to have variety in its definition along time and according to the principle of work and the need of it. Condensers,evaporators, boilers, heaters, coolers ….etc are heat exchangers.Generally, heat exchanger is the device used to transmit heat from one fluid to other one or more fluids.Now, it is clear that heat exchangers have a lot of applications which gives the reason to get a variety in its types (Double pipe, shell and tube, shell and coil, plate type, regenerative …..) , so it is a good chance to discuss briefly every type of heat exchangers. Shell and coil heat exchanger considered compact shell and tube approach, its heat transfer rate is significantly greater because of the secondary flow pattern in planes normal to the main flow. Basically, shell and coil heat exchanger consists of several layers of coiled tubes within a closed shell.In this research, it is known that all shell and coil heat exchangers have their characteristics. At the same time, heat exchangers industry and researches have a new added value every day and this research will try to give a push in that. Numerical investigations will be held to study the improvement of the efficiency of shell and coil heat exchanger by developing its geometry. Conventional shell and coil heat exchanger firstly evaluated and then, four new shell and coil heat exchangers with new and advanced geometrical parameters are investigated. The effect of working conditions on the performance of each heat exchanger is studied.Effectiveness to NTU curve for each coil are obtained and correlated.Numerical results verified. The results show that modified shell and coil heat exchangers had higher heat transfer effectiveness than that for conventional shell and coil heat exchanger by rate varied from 12% and up to 145%. Effect of changes on pressure DROP also investigated. No noticeable changes in pressure DROP recorded along shell side or per coil unit length.