纳米流体轴向旋转热管砂轮成型磨削弧区换热机理研究

To solve the problem of the grinding heat and its damage in the profile grinding of difficult-to-machine materials, a research of the heat transfer mechanism in the grinding zone based on nanofluid rotating heat pipe technology will be conducted. The research intends to adopt lattice Boltzmann method coupled with internal energy distribution function to build the simulation model for the fluid flow behavior and the temperature distribution in the nanofluid rotating heat pipe grinding wheel. Through the numerical calculation and the related experiments, two coupling models for the grinding heat distribution and the surface heat flux on the workpiece related to the parameters of the nanofluid rotating heat pipe will be built respectively. The heat transfer enhancement mechanism and the performance will be studied under different rotational speed, filling ratio and different kind of nanofluids with different nanoparticle kinds, radiuses and volume fractions. Finally, experiments on profile grinding of Ti-6V-4V will be performed using the nanofluid rotating heat pipe grinding wheel and a normal profile grinding wheel. The advantage of controlling the grinding heat in the profile grinding by the nanofluid rotating heat pipe grinding wheel will be evaluated by the grinding temperature, the temperature difference along the workpiece surface, surface integrity, contour accuracy of the workpiece and the quality of the grinding wheel. The research will finally provide a new idea for the controlling of the grinding heat in the profile grinding process.

针对航空航天高强韧难加工材料成型磨削加工中磨削热及其引起的热损伤问题，本项目拟开展纳米流体轴向旋转热管砂轮成型磨削弧区换热机理研究，拟采用格子玻尔兹曼流场计算方法耦合内能分布函数，建立纳米流体轴向旋转热管砂轮内部的流场与温度场计算模型，通过数值计算以及相关换热试验分别建立成型磨削热量分配、工件轮廓热流密度分布与纳米流体轴向旋转热管参数的耦合模型，探明砂轮转速、充液率、纳米流体种类、浓度和粒子大小等对纳米流体轴向旋转热管砂轮强化换热机理与性能的影响机制。最后通过钛合金TC4成型磨削试验，以磨削弧区温度值和型面温差、工件表面完整性与轮廓精度、砂轮表面形貌及磨损等为指标评价其强化磨削弧区换热效果，并与同等条件下普通成型砂轮磨削的结果对比，验证纳米流体轴向旋转热管对成型磨削热的控制优势，为实现成型磨削热的控制提供新的思路。

针对成型磨削加工中磨削热及其引起的热损伤的控制问题，本项目开展了纳米流体轴向旋转热管砂轮的研制、纳米流体轴向旋转热管砂轮的换热机理及性能评价、难加工材料成型磨削试验验证等几个方面的研究，取得的主要创新研究成果如下：.1）揭示了典型成型面磨削加工热损伤机理，提出了针对典型成型面磨削热控制的纳米流体轴向旋转热管砂轮的设计方法。.2）建立了轴向旋转热管砂轮换热性能分析仿真和试验平台，探究了热流密度、砂轮转速、工作介质充液率和纳米流体特性（包括纳米粒子种类、粒径等）对轴向旋转热管砂轮换热性能的影响规律和换热机理，优化了纳米流体轴向旋转热管砂轮的参数。.3）通过钛合金TC4的成型磨削试验验证并评价了轴向旋转热管砂轮的强化换热能力，与同等条件下无热管砂轮成型磨削的结果对比，验证了其对成型磨削弧区热量的控制优势。.该项目通过开展纳米流体轴向旋转热管砂轮成型磨削弧区换热机理研究，完成了成型面磨削烧伤及局部烧伤的控制的目标，并为进一步拓宽热管强化换热技术在难加工材料成型面的绿色制造中的应用提供了重要的理论与技术支撑。.