The Research And Development Of High Temperature Air Preheat Exchangers CAD System

High temperature air preheat exchanger, as an important heat exchanger equipment of waste heat recovery and enhancing thermal efficiency , is widely used in industry of metallurgy, machine, light industry, petro-chemistry, energy power and so on, So the research and development of High temperature air preheat exchanger has being paid more and more attention. Although the design method and standard of high temperature air preheat exchanger is improving day by day, its design have to individuate according to its differently working conditions and user need. The traditional design way of high temperature air preheat exchanger could hardly meet the market need because of its long design period and low design accuracy. So it has important significance for engineering application that the design software system which can realize the functions of technological design calculation, price estimation and CAD parametric automatism drawing was developed.In this thesis, the design software system with automatic design calculation and automatic CAD drawing which can realize the integration of technological design, price estimation and parametric drawing was developed for tubular radiation preheat exchanger, jet preheat exchanger, convection preheat exchanger and their complex air preheat exchangers. Major research results are as follows:(1) Based on the principle of Object-Oriented software and modularized program, the design proposal of the CAD system of high temperature air preheat exchanger including technological design calculation subsystem, price estimation subsystem, parametric drawing subsystem and results export subsystem was brought forward;(2) Based on the principle of design of high temperature air preheat exchanger, the technological design subsystem was developed, which could realize the automatic calculation of thermodynamic parameters and resistance parameters. Especially, a new method which conjunct design calculation and verifying calculation was took in complex air heat exchanger to improve its design precision. (3) According to the results of thermodynamic parameters and resistance parameters, combined the density and unit price of the material of the high temperature air heat exchanger, the price estimation subsystem was developed.(4) Using the new method of positive design calculation and reverse design calculation, a calculation subsystem of the temperature each row pipe at the scoured direction of smoke is founded. It can provide temperature parameter to select material of the pipe.(5) Using AutoCAD 2006 as platform and taking the secondary development, the CAD parametric drawing was achieved, which could carry out the parts drawing and assembly drawing automatically.With widely applicability and friendly interface, this system has run successfully in Hangzhou Meibao Furnace Engineering Co., Ltd. The running results indicate that the system could improve the design efficiency and quality of high temperature air preheat exchanger and it is practicable in engineering applications.