A novel design approach of plate heat exchangers considering the economic impact of chevron angles

Abstract

This work introduces a novel design approach for plate and frame heat exchangers for single and multi-stream units. Chevron-type plate corrugations are commonly used in these exchangers. When the plate length and width are fixed, the corrugation angle becomes a degree of freedom that can be modified to meet a specific heat load. The fact that chevron angles are commercially available at discrete values can limit design options, but this can be overcome by treating the corrugation angle as a design parameter. For the design of a two-stream heat exchanger, using plate dimensions of 0.661 × 0.21 m the best design is obtained for a corrugation angle of 46° and 166 thermal plates. In the case of heat recovery networks, it is shown how five single-phase heat exchangers can be replaced by a single minimum cost multi-stream unit with a plate dimension of 0.661 × 0.21 m and chevron angles for the different process and cold utility streams of: 30°, 38°, 54°,58° and 60° In this application, surface area can be reduced by 95 % and the annualised total cost by $1,283.30 USD, equivalent to 55 % reduction.