Enhancement of Heat Transfer in Straight Pipes

Kumar, Sanjay

Enhancement of Heat Transfer in Straight Pipes by Sanjay Kumar - IIT Jodhpur Department of Mechanical Engineering 2019 - xix,68p. HB

Heat exchangers are widely used devices byindustries in today’s time. Almost every type of industry needs heat exchanger to remove heat from machinery. The efficiency of heat exchanger should be high so that we can perform the task using minimum power uses. There are many techniques usedto increases the efficiency of heat exchanger. The main aim of heat transfer enhancement is reducing the size and operating cost of the system. Swirl generator is the most commonly used devices to heat transfer enhancement due to low cost and easy installation. Numerical simulation for enhancement of heat transfer in horizontal pipes with twisted tapes and perforated twisted tapes of differenttwist ratio are performed. Local and overall Nusselt Number and friction factor across the length for fully developed turbulent flow is obtained. The working fluid inside the pipe was water. Simulation wasperformed in AnsysFluent using k–ω-(SST) model for pipe with twisted tape. All results were performed for smooth pipe, pipe with twisted tapes and pipe with perforated twisted tapes for Reynolds number range 8000 < Re < 50,000, different twist ratios, different heat flux and fixed temperature difference. Results of inserts pipe are compared with results of without inserts pipe flow for same boundary conditions. The thermal-hydraulic performance was calculated for all inserts. Average Nusselt number and pressure drop across length increase with a decreasein twist ratio. The pipe with twisted tapes gives better performance compare to the pipe without twisted tapes. Perforated twisted tapes give better performance compare to twisted tapes. The comparison of thermal-hydraulic performance results helpsto select optimum geometry for shell tube heat exchanger according to their applications.



Heat Transfer in Straight Pipes
MTech Theses
Department of Mechanical Engineering

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