Hall Current Effects on Unsteady MHD Flow in a Rotating Parallel Plate Channel Bound-ed by Porous Bed on the Lower Half—Darcy Lapwood Model

We discussed the unsteady flow of an incompressible viscous fluid in a rotating parallel plate channel bounded on one side by a porous bed under the influence of a uniform transverse magnetic field taking hall current into account. The perturbations are created by a constant pressure gradient along the plates in addition to the non-torsional oscillations of the upper plate. The flow in the clean fluid region is governed by Navier-Stoke’s equations while in the porous bed the equations are based on Darcy-Lapwood model. The exact solutions of velocity in the clean fluid and the porous medium consist of steady state and transient state. The time required for the transient state to decay is evaluated in detail and ultimate quasi-steady state solution has been derived analytically and also its behaviour is computationally discussed with reference to different flow parameters. The shear stresses on the boundaries and the mass flux are also obtained analytically and their behaviour is computationally discussed.

赖朴吾与中国

笔者通过文献档案勾勒还原出赖朴吾的生平,对他的学术成就、在中国的活动包括各个历史时期在燕京大学的工作、抗战时期赴解放区的旅行、与路易·艾黎在"工合"的工作、对成都民主学运的支持,以及推进中英友谊等几方面进行了细致的梳理。展现了赖朴吾与中国的友谊和他的国际主义精神。