Development Of Visual CAD System Of Radial Gate Under UNIX

Radial Gate is one of type of gate used widely in Hydraulic Structure Engineering. Whereas more gates are applied and their design work is more and more burdensome,this paper studies and develops visual CAD system of radial gate based on CAD technique under UNIX platform (HMVCAD System). In this paper,key method is that it takes mixed programming means and human-machine mutual mode to develop CAD system;gives priority to C as master programming language in UNIX graphics workstation;puts to use Fortran working out structure's computing program;adopts OSF/Motif scheming out friendly GUI;utilizes OpenGL function library achieving visualization of design calculation. The CAD system bears biggish theoretical worth and practical application values.Firstly,it introduces the system's developing environment with its correlative method. The system invokes X Window/Motif function library to realize Graphics User Interface on workstation and recommends peculiarity and function of X Windows/Motif. At the same time,it invokes OpenGL graphics library to come true the visualization of data brought out by FEM Pre-processing and Post-processing and introduces OpenGL's performance characteristics and key art in the process of the programming.Secondly,on the base of the analyzing design characteristic,this paper presents theoretical basis according to 'design specification about steel gate in Water Conservancy and Hydropower Engineering '(thereinafter for short specification). It introduces module design means of HMVCAD system. In the light of this means,it develops the module that can design the gate according to original data and specification automatically,the module of making the original design by user's experience,the module of majorized adjustment,the module of alarm device. In succession,this paper recommends the method and operating process of the design of a radial gate with HMVCAD system in detail. In order to raise the system's efficiency,this paper puts forward self-proposed function library,blended data process etc.Finally,this paper adopts advanced spatial thin-walled structure FEM to analyze and compute the designed gate structure,hereby to check initial design's reasonableness by specification and to conduct majorized design. It introduces visualization technique of FEM and makes a visual analysis of the designed gate with HMVCAD. For a project instance,it computes and analyzes the structure of MaDian radial gate with FEM,which achieves the result of gate's structural stress,stiffness and surpport-bar's stability and gives comparative analysis. The computational result suggests this system can solve practical engineering problem rightly and efficiently and owns the biggish applied value.