Three-dimensional MHD simulations of the electromagnetic flowmeter for laminar and turbulent flows

●CFD simulations were performed to study the behavior of a cylindrical electromagnetic flowmeter for both laminar and turbulent flows.●Numerical results show that induced electric potential difference at the electrodes agreed with the theoretical values.●Simulations also render the detailed distributions of induced electric field, current density, electric potential and induced magnetic field.●The numerical methods are useful especially for those complex magnetic field configurations over the analytical methods.

The interaction between an electrically conducting fluid and an external magnetic field in an ideal cylindrical electromagnetic flowmeter is numerically investigated for both laminar and turbulent flows. Induced electric potential in the fluid, and the difference in potential at the measuring electrodes are directly obtained by including MHD effects in the CFD simulations. Fully developed laminar and turbulent flows are simulated. The computed electric potential difference on the electrodes agrees with analytical values for small Hartmann number cases, where the induced Lorentz force is small. Turbulent flow produces a more uniform electric potential distribution in the flow meter cross-section than laminar flow. These integrated MHD/CFD simulations couple the MHD effect with flow dynamics without deriving a weighting function with an assumed velocity profile, which will be necessary for electromagnetic flow meters when the Hartmann number is not small.