为保证微型轴流式血泵的稳定、可靠运行,必须对大间隙磁力传动系统电磁发生装置的温升进行研究和控制.文中通过对磁力驱动系统各部件的温度分布、热量损失、热流密度以及热梯度等热物理参数进行分析,建立了系统电磁发生装置的热场仿真模型;通过有限元仿真及实验研究,得到了系统温度场的分布和变化规律;为保证人体适应性及电磁体的长时间运行,以控制电磁体温升为目标,对电磁驱动系统的电磁参数、运行环境参数等进行了仿真和优化设计.结果表明:减少电磁体损耗和改善电磁体散热条件能够有效降低电磁体温升,当电磁体单个线圈通电电流小于0.56 A、空气流速大于3.5 m/s时,电磁体最高温度不超过50℃.
In order to guarantee stable and reliable operation of micro axial-flow blood pumps,the temperature rise of electromagnet in the large-gap magnetic drive system should be investigated and accurately controlled.In this paper,the temperature distribution,heat loss,heat flux and thermal gradient of various components of the system were analyzed,and a simulation model of the thermal field of the electromagnet was established.Then,the distri-bution and variation law of the system temperature field were obtained via finite element simulation and experiment investigation.Finally,to meet the requirements of human body adaptability and long-term running of the electro-magnet,the electromagnetic and environmental parameters of the electromagnetic drive system were simulated and optimized by taking a suitable temperature rise of the electromagnet as the target.The results show that the tempera-ture rise of the electromagnet can be effectively reduced by decreasing the loss and improving the heat emission con-dition of the electromagnet;and that the highest temperature of the electromagnet does not exceed 50℃ when the current of electromagnet coils is lower than 0.56 A and when the air velocity is higher than 3.5 m/s.