A general and rapid method for performance evaluation of enhanced heat transfer techniques

Evaluation of the comprehensive performance of different heat transfer technologies and selection the best enhanced surface to meet the requirements are of great significance for efficient energy recovery. In this paper, based on the previous research results from our group, a rapid multi-criterion comprehensive evaluation method of enhanced heat transfer surfaces was first proposed; it realizes the rapid evaluation of heat transfer performance under the condition of equal flow rate, equal pressure drop and equal pump power constraints. Three baselines divide evaluation plot into six zones, namely zone 1 (non-energy-saving zone), zone 2 (relative energy-saving zone), zone 3 (value-added energy-saving zone), zone 4 (ideal energy-saving zone), zone 5 (pure energy-saving zone), and zone 6 (simple energy-saving zone). A simplified evaluation plot was then developed to overcome the dependence on the correlations of the reference surface. Next, the prediction results of the evaluation plot under the condition of variable minimum flow cross-section area, variable total heat transfer area, variable equivalent diameter, and variable tube bundle arrangement were compared with the traditional method to verify the applicability and accuracy of the evaluation plot. Finally, numerical simulations and engineering application of typical heat transfer surfaces were conducted to compare the energy-saving effectiveness of different enhanced surfaces and to analyze the effect of geometry and operation parameters on comprehensive performance. The results showed that the evaluation chart established in this paper can be successfully applied to the comprehensive comparison of multiple evaluation criteria and has a high prediction accuracy. Compared with the common evaluation methods, this method has excellent practicability and visualization, and contributes to the rapid development of new enhanced surfaces and efficient utilization of energy.