화학공학소재연구정보센터
International Journal of Heat and Mass Transfer, Vol.84, 990-997, 2015
Experimental investigation on performance comparison for shell-and-tube heat exchangers with different baffles
An improved structure of ladder-type fold baffle is proposed to block the triangular leakage zones in original heat exchangers with helical baffles. The numerical results showed that the distribution of shell-side velocity and temperature in improved heat exchanger are more uniform and axial short circuit flow is eliminated. The experimental results showed that the shell-side heat transfer coefficient alpha(0) and overall heat transfer coefficient K are improved by 22.3-32.6% and 18.1-22.5%, respectively. The increment in shall-side pressure drop is about 0.911-9.084 kPa, while the corresponding pumping power penalty is about 2-80W. The thermal performance factor TEF enhances by 18.6-23.2%, which demonstrates that the ladder-type fold baffles can effectively improve the heat transfer performance of heat exchangers with helical baffles. The results of this paper are of great significance in the optimal design of the heat exchanger. (C) 2015 Elsevier Ltd. All rights reserved.