格库铁路HDPE板沙障孔隙率与有效防护距离关系

Relationship between Porosity and Effective Protection Distance of HDPE Board Sand Barrier on Golmud—Korla Railway

以格库铁路路基风沙防护为背景,基于ANSYS软件中欧拉双流体非定常模型,运用数值模拟方法,研究HDPE板沙障孔隙率与有效防护距离的关系。结果表明:HDPE板孔隙率较小时,在HDPE板沙障周围气流分别形成减速区、加速区、高速区、回流区、速度突增区和消散恢复区;随着孔隙率的增大,气流的高速区、速度突增区和回流区的面积减小并逐渐消失;孔隙率小于50%时,随着HDPE板孔隙率的增大,有效防护距离逐渐增大,有效防护距离与孔隙率呈一元二次函数分布,孔隙率大于50%时,随着HDPE板孔隙率的增大,有效防护距离逐渐减小,有效防护距离与孔隙率呈指数函数分布,因此HDPE板沙障最优孔隙率在50%左右。

With the wind and sand protection for the subgrade of Golmud-Korla Railway as background, based on the Euler two-fluid unsteady model in ANSYS software, the relationship between the porosity and the effective protection distance of HDPE board sand barrier was studied by numerical simulation. Results show that when the porosity of the HDPE board is small, the airflow around HDPE board sand barrier forms deceleration zone, acceleration zone, high-speed zone, recirculation zone, velocity sudden increase zone and dissipation recovery zone respectively. With the increase of porosity, the area of high-speed zone, velocity sudden increase zone and recirculation zone decreases and gradually disappears. When the porosity is less than 50%, the effective protection distance increases gradually with the increase of the porosity of HDPE boards, and the effective protection distance and the porosity show a quadratic function distribution. When the porosity is greater than 50%, the effective protection distance decreases gradually with the increase of the porosity of HDPE boards, and the effective protection distance and the porosity have an exponential function distribution. Therefore, the optimal porosity of HDPE board sand barrier is about 50%.