Simulation Study On The Windproof Effectiveness Of The Larch Windbreak Forest Structure

My country's forest coverage is low and vulnerable to wind damage,and windbreaks can reduce wind speed behind forest belts.The structure of windbreak forest belt is the main factor affecting windbreak efficiency.At present,wind speed measurement after windbreak forest belts is inefficient,susceptible to factors such as time or weather,and the analysis of windbreak effectiveness is mainly based on qualitative analysis,which has certain limitations.In order to provide scientific and reasonable guidance for the construction of windbreaks quickly and accurately,computer analysis technology and intelligent algorithms were used to study the windbreaks.This is of great significance for the construction of windbreaks.The main work of the paper is as follows:(1)Based on the image processing technology,a method for calculating porosity of the windbreak is designed.Digital cameras were used to obtain images of different structures of artificial larch forest belts with white background boards,and then the images were preprocessed.Through comparative analysis,Otsu threshold segmentation was used to segment windbreak forest images.Furthermore,the calculation of the windbreak forest permeability was completed.(2)Established a dominant relationship model between windbreak forest porosity and forest belt structural factors.First,through linear correlation analysis,the structural factors of forest belts that are significantly correlated with porosity are the number of forest belt rows,the number of trees,the proportion of under branches,the spacing between trees,and the density.Then,a stepwise linear regression method was used to establish the dominant factor model for the porosity,number of rows,and density.The results show that dominance factor model of windbreak forest belt has a higher fitting accuracy,R2 reaches 0.96,the average relative error is 10.04%,and the accuracy is higher.(3)The models of wind protection effectiveness of windbreaks with different structures were established.A statistical model for the windproof effectiveness of windbreaks with different structures was established by the curve parameter estimation method,and a model selection method based on goodness of fit was proposed.The results shows that Fourier model had the best effect on fitting the windbreak effect relationship model of different width forest belts,and R2 was above 0.98.SSF model had the best effect on fitting the windbreak effect relationship of different spacing forest belts,with the lowest coefficient of determination(R2)being 0.89.According to the constructed statistical model,a windbreak forest structure with two rows and one belt or a tree spacing of 8m×8m was recommended.(4)Establish wind speed simulation models of forest belts with different structures and display them visually.The windbreak forests of different structures are clustered by the improved K-Means++clustering algorithm,and the windbreak forest belts are divided into 3 categories,category ?(1,2,5),category ?(3,4,7)and category ?(6,8).Use Matlab to call Surfer8.0 to visually display the wind field of forest belts of different structural categories.