高速土工离心机温升的数值模拟

Numerical Simulation on Temperature Rise of High-speed Geotechnical Centrifuge

目的数值计算高速土工离心机机室温度分布,研究不同真空度和侧壁温度对机室温升的影响,并为高速土工离心机提出温控方案。方法针对一款在建的高速土工离心机,采用SRF方法和RNG k-ε湍流模型对其进行数值计算,对比不同转速下离心机的温升。针对加速度为1500g的运行工况,对比不同机室压力和侧壁温度对机室温升的影响。结果高速土工离心机以1500g加速度运行时,机室最高温度可达83℃。运行压力从100 kPa降至3 kPa,机室最高温度下降约15℃,侧壁温度每降低10℃,机室最高温度降低约5℃。另外,真空度配合侧壁冷却无法满足散热要求时,可考虑在机室顶部靠侧壁布置面积不小于顶部面积1/4的冷却环。结论利用CFD数值计算方法,定量得到了高速土工离心机机室温度随转速、真空度和侧壁温度的变化,为其冷却方案的设计提供了参考。

The work aims to conduct numerical calculation of the temperature distribution in the machine room of high-speed geotechnical centrifuges,study the effects of different vacuum degree and side wall temperature on the temperature rise of the machine room,and propose a temperature control scheme for high-speed geotechnical centrifuges.In this work,the SRF method and the RNG k-ε turbulence model were adopted to conduct numerical calculation and compare the temperature rise of the centrifuge at different speed.Under the working condition with an acceleration of 1500 g,the effects of different machine room temperature and side wall temperature on the temperature rise of the machine room were compared.The results revealed that the maximum temperature in the machine room could reach 83℃ when the high-speed geotechnical centrifuge ran at an acceleration of 1500 g.The maximum temperature in the machine room dropped by about 15℃ when the operating pressure was reduced from 100 kPa to 3 kPa,and every time the temperature of the side wall decreased by 10℃,the maximum temperature of the machine room decreased by about 5℃.In addition,a cooling ring with an area not less than 1/4 of the top area could be arranged on the top of the machine room against the side wall when the vacuum degree and side wall cooling cannot met the requirements of heat dissipation.Based on CFD numerical calculation method,the changes of machine room temperature of high-speed geotechnical centrifuge with speed,vacuum degree and side wall temperature are quantitatively obtained,providing a reference for design of cooling schemes.