Abstract
Numerous passive heat transfer enhancement techniques (including various types of turbulators) have been proposed before for heat exchangers by many researchers. Their thermal/frictional behaviors have been reported in-detail in term of Nu number, friction factor and so on. However, their economic characteristic has been always immature which is because of lack of an explicit economic criterion (with clear economic unit i.e. dollar per unit of time etc.) applicable for any passive technique through any type of heat exchanger. Hence, this research aims to propose an explicit economic criteria (with a final clear formula) to evaluate the production cost rate of heated/cooled fluid through any type of heat exchanger (with or without passive technique) taking into account all effective parameters (such as capital cost, pumping power, exergy related costs, electricity price of the region, thermal and fluid flow condition through the heat exchanger, ambient condition and so on) and without dependency of other equipment that may work in-line with heat exchanger. The model is developed based on the general standard Specific Exergy Costing theory. The proposed model is a strong economic criterion tool, optimization tool and also comparison tool between different passive heat transfer enhancement methods. Case study as an example application of the model is provided at the last part of the paper.
•A novel explicit strategy is proposed for passive techniques of heat exchangers.•The model is based on standard Specific Exergy Costing Theory.•The final outcome of the model is an interesting explicit formula.•All effective parameters on economic parameters are considered.•A case study is presented as an example application of the model.