FACULTY OF TECHNOLOGY
Permanent URI for this communityhttps://repository.ui.edu.ng/handle/123456789/269
Browse
3 results
Search Results
Item Numerical investigation of the concave-cut baffles effect in shell-and-tube heat exchanger(2019) Petinrin, M. O.; Dare, A. A.In this paper, the performance of shell-and-tube heat exchangers with single-segmental baffle and varying configurations of concave-cut baffles (10, 15 and 20 %) was investigated. The study was carried out for a heat exchanger having either engine oil, water and air as shell-side fluid. For each configuration of the baffles, the results of both the k-ε and RNG k-ε turbulent models were in very close agreement. The heat exchangers with concavecut baffles had higher pressure drops and lower performance factors than that of single-segmental baffle at the same range of mass flow rates for all fluid cases. Also, the concave-cut baffle heat exchangers had lower shell-side heat transfer coefficients at the same pressure drop against that of single-segmental baffles. Thus, the use of concave-cut baffles did not exhibit desirable performance in heat exchanger as compared with the segmental baffles.Item Numerical investigation of shell-and-tube heat exchanger with parabolic segmental baffle cut(2019-01) Ikpotokin, I.; Uguru-Okorie, D. C.; Osueke, C. O.; Dare, A. A.; Petinrin, M. O.An investigation was carried out on the effect of the use of a parabolic baffle at different baffle cuts on the performance of shell and tube heat exchangers. The numerical study was performed on a personal computer with 12 GB RAM and Intel® Core™ i7 2.50GHz CPU using a CFD software Comsol Multiphysics. The modeled heat exchanger had 37 tubes, shell internal diameter of 200 mm, 6 baffles with baffle spacing of 100 mm. The results from the effect of mass flow rate and baffle cut on heat transfer rate and pressure drop in the shell side of the heat exchanger were compared with the circular segmental baffle cut of 25% and that of the parabolic baffle cut of 25 and 30% of the inner shell diameter. At 25% of the shell diameter baffle cut, the parabolic cut had an improved heat transfer rate compared to that with the circular segmental baffle cut with a drawback of higher pressure drop. As the parabolic baffle cuts increased, there was a decrease in heat transfer rates and pressure drops at the various mass flow rates considered. At 30% of shell diameter cut, the performance of the parabolic segmental baffle cut gave results similar to the circular segmental baffle cut at 25% of the inner shell diameter. The investigation showed that for a parabolic baffle cut, 30% of the shell diameter is recommended for optimum performance.Item Numerical modelling of effect of baffle orientation offset on shell-and-tube heat exchanger performance(2018-02) Petinrin, M. O.; Dare, A. A.The performance of a shell-and-tube heat exchanger (STHE) is largely dependent on the type, orientation and offset arrangement of the baffles employed. In this paper, the thermal-hydraulic characteristics of STHEs with 90°, 120° and 180° offset arrangements of baffles were studied numerically. The study was performed on 19-tube and 31-tube heat exchangers, and also for three shell-side working fluids: air, water and engine oil. The numerical analyses were carried out using the k-ε model with imposed realizability constraint, and were solved with COMSOL Multiphysics. The STHE with 180° had higher pressure drop than other STHEs for all the ranges of mass flow rate. STHE with 120° showed better performance for shell-side heat transfer coefficient at the same pressure drop while STHE with 90° had much higher performance factor at the same mass flow rate. It is concluded that baffle offset arrangements significantly affected the shell and tube heat exchanger performance.