【作者】 李辉；

【导师】 周本谋； 刘宗凯；

【作者基本信息】 南京理工大学 ， 流体力学， 2017， 硕士

【摘要】 本文利用电磁体积力可控制流体边界层来研究其对对流换热的影响。对于电磁体积力边界层控制是流动控制研究中极具特色的控制方法,与其它控制方法相比,它更为简便,操作更为灵活。而本文结合对流换热特性、电磁流体控制和随机穿越模型,展开如下研究:1.本文研究了电磁体积力作用于圆柱周围对对流换热的影响。利用圆柱绕流对流换热经验公式、商业软件fluent计算结果与本文数值计算结果进行对比验证了数值方法的正确。研究结果表明平均努塞尔数随电磁体积力增大表现出先增大后减小最后再增大的作用效果。2.本文研究了流向电磁体积力对弹体对流换热作用效果。研究分两种壁面受热情况进行的。一是弹体整体壁面受热,二是弹体局部壁面受热。研究结果表明随着电磁体积力增大弹体壁面对流换热被逐渐强化。3.针对不稳定热源,本文引入了随机穿越模型来描述此类不稳定热源。数值计算结果表明给定热源随机穿越周期,其对流换热的传热速率也成周期性变化。在弹体边界层施加流向电磁体积力后,计算结果表明流向电磁体积力仍能强化弹体局部受随机穿越热源的对流换热,且随着时间的推移,强化效果越明显。对于流向电磁体积力的增大,弹体局部壁面对流换热传热速率也越来越大,但传热速率增大的幅度越来越小。更多还原

【Abstract】 In this paper,the effect of electromagnetic force on the convective heat transfer is studied.The boundary layer control of electromagnetic force is a special control method in the study of flow control.Compared with other control methods,it is more convenient and flexible.In this paper,combined with the characteristics of convective heat transfer,electromagnetic fluid control and random crossing model,the following research:1.The effect of electromagnetic force on the convective heat transfer around a cylinder is studied.The numerical results are compared with the results of numerical calculation by using the empirical formula of convection heat transfer around the cylinder and the calculation results of commercial software fluent.The results show that the average Nusselt number with the electromagnetic force increases showed first increased and then decreased and finally increased the effect.2.The effect of electromagnetic force on the convective heat transfer is studied.The study is divided into two kinds of wall heating.The first one is that the whole wall of the missile body is heated,and the two is heated by the local wall of the missile body.The results show that the convective heat transfer is enhanced gradually with the increase of electromagnetic force.3.For the unstable heat source,this paper introduces the random crossing model to describe this kind of unstable heat source.The numerical results show that the heat transfer rate of the convective heat transfer in a given heat source is changed periodically.The flow of electromagnetic force applied in the body boundary layer,the calculation results show that the flow of electromagnetic force still can strengthen the body of local convective heat exchange through random,and with the passage of time,the strengthening effect is more obvious.With the increase of the streamwise electromagnetic force,the heat transfer rate of the heat transfer coefficient of the local wall is larger and larger.更多还原