三维屋面积雪分布的数值仿真与风洞试验研究

发布时间：2018-01-11 10:07

本文关键词：三维屋面积雪分布的数值仿真与风洞试验研究　出处：《西南交通大学》2017年硕士论文　论文类型：学位论文

【摘要】：突如其来的风雪灾害会给人们的生产生活带来巨大的威胁,屋面上大量的不均匀雪荷载会致使房屋结构坍塌。本文回顾了国内外的相关研究,归纳、总结了风致雪漂移的基础理论,从数值仿真和风洞试验两方面入手,着重研究屋面积雪分布特征,提出了一种数值模拟方法。本文主要完成了如下几个方面的工作:(1)建立了一种基于FLUENT提供的Mixture两相流模型和准静态方法的数值模拟方法,并同时考虑了积雪预铺和休止角的影响。使用文献中的二维平屋面模型做二维模拟,对这种数值仿真方法进行验证。(2)对三维平屋面进行数值仿真,分析平屋面屋面粒子深度分布特征和模型高宽比对模型屋面粒子深度分布的影响。(3)对三维双坡屋面进行数值仿真,分析双坡屋面粒子深度分布特征和屋面坡度对屋面粒子深度分布的影响。(4)从几何、启动条件、运动以及时间等方面,分析研究风致雪漂移风洞试验应该满足的相似率。(5)使用石英砂作为雪模型的粒子,对三个不同高宽比的三维平屋面和两个不同坡度的双坡屋面进行风洞试验。试验中分别测定了不同名义风速下的流场特征和石英砂的休止角,对两组模型进行了若干组工况下的屋面积雪分布的风洞试验,分别测定了不同风速、不同时间的屋面粒子深度分布,分析不同高宽比对平屋面屋面粒子深度分布的影响和屋面坡度对双坡屋面粒子深度分布的影响。(6)将积雪分布的数值仿真结果与风洞试验的相关结果进行对比分析。
[Abstract]:Sudden snow disasters will bring a great threat to people's production and life, and a large number of uneven snow loads on the roof will lead to the collapse of the housing structure. This paper reviews the relevant studies at home and abroad, summarized. The basic theory of wind-induced snow drift is summarized in this paper. From the aspects of numerical simulation and wind tunnel test, the characteristics of snow cover distribution in roof are studied emphatically. A numerical simulation method is proposed in this paper. The main work of this paper is as follows: 1). A numerical simulation method based on Mixture two-phase flow model and quasi-static method provided by FLUENT is established. At the same time, the effects of snow prelay and angle of repose are considered. The 2D flat roof model in literature is used to do two-dimensional simulation, and the numerical simulation method is verified. 2) the three-dimensional flat roof is numerically simulated. The characteristics of particle depth distribution in flat roof and the influence of model height to width ratio on the depth distribution of roof particles are analyzed. The characteristics of particle depth distribution on double slope roof and the influence of roof gradient on the depth distribution of roof particles are analyzed. (4) from geometry, starting condition, motion and time, etc. The similarity rate to be satisfied in wind drift wind tunnel test is analyzed. 5) the quartz sand is used as the particle of snow model. Wind tunnel tests were carried out on three three dimensional flat roofs with different aspect ratios and two double sloping roofs with different slopes. The flow field characteristics and the angle of repose of quartz sand under different nominal wind speeds were measured respectively. Wind tunnel tests of snow cover distribution on roof under several working conditions were carried out in two groups of models, and the depth distribution of roof particles with different wind speed and time was measured respectively. The influence of height to width ratio on particle depth distribution of flat roof and the influence of roof slope on particle depth distribution of double slope roof are analyzed. The numerical simulation results of snow cover distribution are compared with those of wind tunnel test.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU312.1

【参考文献】