
[Sponsors] 
May 27, 2001, 23:35 
MHD Benchmark

#1 
Guest
Posts: n/a

Sponsored Links


Sponsored Links 
May 31, 2001, 17:07 
Re: MHD Benchmark

#2 
Guest
Posts: n/a

I solved some 2D and 3D MHD problems in my PhD using CFX.
Some details follow, please feel free to contact me if you want to know more. Title "Coupled heat/species transfer and buoyancydriven magnetohydrodynamic convection" Author Duncan Maclean, Department of Engineering, University of Cambridge, December 2000. Abstract: This thesis presents a numerical and analytical study of the effects of a steady magnetic field on thermal and solutal buoyancydriven convection in liquid metals and liquid semiconductors of electricity. Of particular interest is the coupling between the heat/species transfer and the magnetohydrodynamic equations when the magnetic field is strong. Numerical simulations with commercial CFD codes which are modified to account for the electromagnetic effects are used to validate all of the analysis. The work on solutal buoyancydriven convection relates specifically to longcapillary methods for determining coefficients of molecular diffusion. The work on thermal buoyancydriven convection is fundamental and may have applications where convective effects are dominant such as semiconductor crystal growth and the design of nuclear fusion reactors. An effective diffusivity model is developed for mass transport by molecular diffusion and unsteady solute buoyancydriven convection in a horizontal capillary by a method similar to that used for Taylor dispersion in forced flow. A 1D nonlinear diffusion equation is obtained and an analytical asymptotic solution is found for dominant convective mass transport. A scaling analysis clarifies the boundary between dominant molecular diffusion and dominant convective mass transport. The use of a steady vertical magnetic field for liquid metals and semiconductors is found to damp the convective mass transport by a factor of $H\!a^{4}$ where $H\!a$ is the Hartmann number. Thermal buoyancydriven convection in a tall cavity is studied for cases where there is a strong magnetic field and heat transfer is predominantly convective, this requires respectively that $H\hspace{0.05cm}a$ and $Ra/H\hspace{0.05cm}a^{2}$ are large where $Ra$ is the Rayleigh number. A 3D analytical model is developed for conditions of uniform heat flux on two opposite sidewalls with the magnetic field parallel to the imposed thermal gradient. In the asymptotic limits the core is stationary and thermally stratified with all the flow passing through thin boundary layers. Analytical solutions are obtained for velocity and temperature fields and a Nusselt number based on the temperature difference between the heated walls is found asymptotically to approach $\frac{1}{2}\left( Ra/H\hspace{0.05cm}a^{2}\right) ^{2/5}$. An idealistic 2D model of the same cavity is considered but with uniform and different temperatures on the sidewalls. The core is again thermally stratified and has only a horizontal component of velocity. Approximate analytical solutions are obtained for velocity and temperature and an average Nusselt number is found to be $\sqrt{LRa/H\hspace{0.05cm}a^{2}H}$ where $H$ and $L$ are the height and width of the cavity respectively. Numerical results are presented for a 2D square cavity which is tilted at some angle and subject to a vertical magnetic field with uniform heat flux through two opposite sidewalls. These results confirm asymptotic analytical solutions by Cowley (1996)\ for velocity, temperature and Nusselt number, the latter being a function only of the angle of tilt. 

June 24, 2010, 11:03 
Mhd

#3 
New Member
Paul Rodriguez
Join Date: Jun 2010
Posts: 4
Rep Power: 9 
Dear Duncan Maclean,
I am trying to find your published paper on "Coupled heat/species transfer and buoyancydriven magnetohydrodynamic convection" but I have had no luck in finding it. I also had another question regarding MHD, where can I find tutorials specifically on MHD. Thanks 

August 29, 2011, 21:36 

#4 
New Member
Habib
Join Date: Aug 2011
Posts: 2
Rep Power: 0 
i am very interested to have a copy of your work thak u in advance


August 29, 2011, 21:37 

#5  
New Member
Habib
Join Date: Aug 2011
Posts: 2
Rep Power: 0 
Quote:


Thread Tools  
Display Modes  


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
MHD BPISO etc  Dr B.M. Smith (Smith)  OpenFOAM Running, Solving & CFD  8  November 14, 2012 11:23 
B vector in mhd module.  adamo  Fluent UDF and Scheme Programming  7  May 22, 2012 06:26 
Euler3d Benchmark  Verdi  Hardware  2  May 26, 2011 06:21 
SIG HPC Benchmark  jens_klostermann  OpenFOAM  0  October 1, 2009 18:20 
benchmark test case for MHD RT instability  cou  Main CFD Forum  0  May 7, 2007 09:38 
Sponsored Links 