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Magnetic Field and Water Electrolysis Work

  1. Aug 26, 2014 #1
    Greetings everyone!

    I recently read a research paper on the effects of a magnetic field on redox potential of water (Magnetic Field Effects on Redox Potential of Reduction and Oxidation Agents), but the paper didn't include any of the equations related to the internal energy of the system.

    Another paper (Magnetohydrodynamic Propulsion for the Classroom) stated magnetohydrodynamic (MHD) force (on water) as F = qv x B, where qv = (qnAL)v. The n is the number of charges per volume and A and L are the cross-sectional area and length of the channel or container. The quantity qnAv will define the current I. The paper stated "This leads to the statement for the force imparted on a current in the presence of a magnetic field", which redefines the equation for force as F = LI x B, with B as the magnetic field.

    The work for the electrolysis of water is calculated as W = PΔV. Considering the listed equations, is there an equation to calculate the work done to the system within a magnetic field? Any help is greatly appreciated.
    Last edited: Aug 26, 2014
  2. jcsd
  3. Sep 4, 2014 #2
    I'm sorry you are not finding help at the moment. Is there any additional information you can share with us?
  4. Sep 4, 2014 #3
    Thank you for responding Greg!

    I'm trying to find an equation to calculate the change in internal energy for water electrolysis within a magnetic field perpendicular to the current; magnetohydrodynamics (MHD). The cross products of current I and magnetic field B generates a force F perpendicular to the magnetic field; Lorentz Force. Considering that the equation for the system work of water electrolysis is W = PΔV, how would I rewrite this equation to include a magentic field perpedicular to the current?

    I've uploaded 12 pages from the research paper "MHD Propulsion" - Sutcliffe & Neiser 2009. It includes an example of the equation for MHD thrust: F = IL X B. Any help is greatly appreciated.

    Attached Files:

  5. Sep 11, 2014 #4
    Magnetohydrodynamics, Internal Energy, and System Work


    I've only found 1 paper with equations for the internal energy: "Magnetohydrodynamic Electrochemistry in the Field of Nd−Fe−B Magnets. Theory, Experiment, and Application in Self-Powered Flow Delivery Systems" - Leventis & Gao 2001. I found it very confusing. I'll post the 3 pages that have the formulas. Any help is greatly appreciated.
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