Abstract. The negative pressure valve EGR bears thermal load for a long period, thus its heat transfer characteristics have an important impact on the stability of the engine. The fluid solid coupling method was employed to analyze the contact heat transfer between the inner cavity of the valve and the cooling water as well as the high temperature gas based on CFD. As a result, the characteristics of the internal fluid velocity field, pressure field and temperature field were obtained. Besides, the heat transfer capability of the valve was also improved by adding the annular cooling water channel. The test results showed that the calculation method has a high calculation accuracy providing an important basis for the optimization design of valves.

The type of disc brake has excellent efficiency and strong heat dissipation, which are beneficial to the transport capacity for mining motor vehicles. To ensure the reliability of the brake, the two-dimensional heat transfer differential equation model of disc brake is established, considering the dynamic change of convective heat transfer coefficient. The heat boundary conditions are established through the characteristics of brake disc structure and air condition, which is more accuracy than the traditional simplified method. Based on the PDE module in MATLAB, the mathematical model of heat transfer is solved and the transient temperature field is obtained. The calculation results are verified by the temperature field of the brake disc Link3900 NVH test platform. The results show that the research scheme has high computation accuracy, and can provide important basis, new ideas and advanced methods for the brake of mining motor vehicle in related fields.