Research On Parametric Modeling Of Irregular Buildings And Its Wind Carrier Coefficient

AutoCAD is currently the main channel for building irregular building models,and its powerful graphics processing functions provide support for building complex models.However,as the complexity of the model increases,the modeling time continues to increase.At the same time,there is little research on model quality control.Poor model quality can easily lead to distortion or non-convergence of calculation results.To this end,starts from the two aspects of model quality control and model efficiency improvement,the main research contents include:1.Classify buildings according to modeling characteristics.The limitations of traditional modeling methods are summarized from the modeling process based on various buildings.There are many control points for irregular building models,AutoCAD can only process a single control point at a time,so the modeling efficiency is low;the model regularity caused by the compatibility problems of drawing and analysis software complicates the modeling process;Some of AutoCAD’s plane drawing functions can not be used directly in three-dimensional space,and other commands are needed to assist,resulting in fragmentation of the modeling process.2.Deducing modeling control parameters that can form a higher quality grid based on variables such as control point spacing,layer spacing,interlayer variation status,etc.,and providing corresponding triangle grid drawing and optimization programs for point sets with special distributions that can easily form poor quality grid Programs.3.Regarding the limitations of traditional modeling methods,Autolisp language is used for secondary development based on AutoCAD software.In the steps of point set screening,leveling uniformity,contour drawing,interlayer stitching,etc.,with batch processing of point sets as the core,one or more shortcut functions have been developed to improve modeling efficiency;The vertex area rendering scheme is developed to simplify the modeling steps.4.Analyze the factors that affect the accuracy of the calculation results during the numerical wind tunnel simulation.The analysis shows that the division of the grid has a greater impact on the calculation results than the choice of the turbulence model.The surrounding encryption grid division method can form a denser grid at the place where the pressure gradient is larger,and the number of grids is reasonable,which guarantees the reliability of the calculation results and has high calculation efficiency.5.Taking the King Saar statue as an example,the parametric modeling method is used for modeling,and the wind carrier type coefficient and surface wind pressure distribution law are analyzed.In the convex or concave parts with a large wind bearing area on the windward surface,it is easy to form a high wind pressure area,and the outward pressure of the high pressure area gradually decreases.