Improvement of engineering methodology of design of shell-and-tube heat exchangers in MathCad mathematical system

Abstract

The problems of optimal design of shell-and-tube heat exchangers, widely spread in industry, acquire new aspects of relevance due to the rapid development of digital design technologies and computer mathematics systems. The review of works of domestic and foreign researchers in the field of design of shell-and-tube heat exchangers is carried out. The aim of the work is to increase the efficiency of shell-andtube heat exchanger design by applying the methods of optimal design. Materials and methods. The traditional method of calculation of shell-andtube heat exchanger is analyzed, on the basis of which the ways of its modernization are determined A new calculation scheme consisting of three parts is proposed. In the first part, formulas and reference data are used, the calculation and selection of which do not require the use of search procedures. The second part consists of a set of functions describing the design parameters of the heat exchanger, the arguments of which are control parameters. The third part of the method solves the optimization problem of obtaining the extremum of the target parameter under the action of a number of constraints on the structural parameters of the apparatus. To verify the efficiency of calculations, a parametric solid-state model of the heat exchanger is used, with the use of which the thermal-hydraulic calculations were carried out. The results of the research. On a concrete example it is shown that the proposed methodology of optimal design of shell-and-tube heat exchanger allows to obtain a design with minimum total weight of tubes. A number of calculations of the heat exchanger are carried out to illustrate that it is practically impossible to achieve the optimal parameters of the apparatus by methods of “manual counting”. Thermal-hydraulic calculation of the optimal design of the apparatus showed good adequacy of the results obtained by the proposed method and the data of thermal calculation with the help of CAD-system.