In view of the development status of high-reliability and low-cost cooling technology for radial turbine of micro-gas turbine or vehicle turbocharger, the impingement cooling technology of the radial turbine back disc was proposed, and the improvement of the cooling efficiency and thermal stress of the turbine back disc was numerically simulated. The results show that the impingement cooling technology can greatly improve the cooling efficiency of the turbine back disc and reduce the stress level. When the relative cooling flow is 1.0%–3.0%, the average cooling efficiency of the lower part of the turbine back disc is increased by 258%–486% compared with no cooling, which can reduce the thermal stress at the fillet of the back disc by 140–216 MPa. Both the average cooling efficiency and the fillet stress of the back disc increase slightly as the relative position of the jet hole moves outward. When the relative cooling flow is controlled within 2.0%, the effect of this cooling technology on the performance of the turbine can be ignored.

鉴于微型燃气轮机或车辆涡轮增压器径向轮机的高可靠性，低成本的冷却技术的发展现状，提出了径向轮机背盘的冲击冷却技术，提高了冷却效率和热效率。对涡轮后盘的应力进行了数值模拟。结果表明，冲击冷却技术可以大大提高涡轮后盘的冷却效率，降低应力水平。当相对冷却流量为1.0％–3.0％时，与不进行冷却相比，涡轮机后盘下部的平均冷却效率提高了258％–486％，这可以减少后部圆角处的热应力盘在140–216 MPa之间。随着喷射孔的相对位置向外移动，后盘的平均冷却效率和圆角应力都会略有增加。当相对冷却流量控制在2.0％以内时，可以忽略这种冷却技术对涡轮机性能的影响。