液黏调速离合器中摩擦副间隙内流体传热分析

为了研究流体润滑条件下液黏调速离合器摩擦副间隙内流体主要传热方式的问题,分别建立等温、绝热及对流换热3种热边界条件下流体流场的简化数学模型,并考虑流体黏温特性的影响,采用商用计算流体动力学软件Fluent对流场进行求解,分别获得等温、绝热及对流换热条件下流场温度分布的数值解；在数值计算的基础上,利用液黏调速离合器实验装置分别测量不同输入转速及输入流量条件下摩擦副间隙内流体温度.研究结果表明等温边界条件下的数值计算结果与实验测试结果比较接近,绝热边界条件下的数值计算结果与实验结果之间偏差最大；流场温度随着摩擦副间隙或输入流量的增加而降低,随着输入转速的增加而增加.

Heat transfer in the gap of friction pairs in hydroviscous drive

The temperature distribution of the flow between friction pairs which run under condition of full fluid lubrication was researched in order to determine the main form of heat transfer in hydroviscous drive. The simplified mathematical model for the flow under isothermal, adiabatic and convective thermal boundary conditions were built, taking into account the effect of viscosity-temperature characteristics. The flow between friction pairs was solved by using the commercial computational fluid dynamics code FLUENT. Numerical temperature results were obtained accordingly. Based on the numerical simulations, temperature distributions under different condition of input rotational speed and input flow rate were measured on the hydroviscous drive test rig. It is shown that experimental data are close to numerical results under isothermal thermal boundary condition and deviate badly from that under adiabatic boundary condition. In addition, it is found that temperature decreases as either the gap or input flow rate increases, but it increases as input rotational speed increases．