离心机气动产热及其影响因素的理论研究

Theoretical study on aerodynamic heat generation of centrifuge and its influencing factors

为深入解析离心机气动产热的影响因素和变化规律,理论推导建立产热模型,并通过与文献中离心机的气动产热实验和仿真结果的对比,验证了理论模型的有效性。利用该模型对实际的离心机产热问题进行分析计算发现:在所研究的工况范围内,机室内空气的随流比随转子转速ω_(r)的增加而增加;产热总功率与转子转速呈指数上升关系,与机室压力呈正比例关系;机室侧壁的摩擦产热功率在离心机气动产热热源中的占比最大,且随着ω_(r)的增加而增加。建议将离心机的换热器布置在机室侧壁内表面并人为提高机室内空气的随流比,以利离心机散热控温。

In order to deeply analyze the influencing factors and their change laws of aerodynamic heat generation of centrifuge,a heat generation model was theoretically derived and established.The effectiveness of the theoretical model was verified by comparing the experimental and simulation results of the aerodynamic heat generation of centrifuge in the literature.The model was used to analyze and calculate the actual centrifuge heat generation.It is found that the air flow ratio in the chamber increases with the increase of rotor angular velocity ω_(r) in the range of working conditions studied.The total heat generation power increases exponentially with the rotor speed and is proportional to the chamber pressure.The friction heat generation power of the chamber side wall is the largest among all heat sources of the centrifuge and increases with the increase of ω_(r).It is suggested that the heat exchanger of the centrifuge be arranged on the inner surface of the chamber side wall to artificially improve the air flow ratio in the chamber,so as to facilitate the heat dissipation and temperature control of the centrifuge.