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A one-dimensional full fluid moment model is developed to study shear-induced electron transport in low-temperature, partially magnetized plasmas. Ions and electrons are treated as two different fluids that interact with each other through collisions and electromagnetic fields. Conservation of mass, momentum, and energy is solved for both the fluids and the Poisson equation is solved to obtain the electrostatic electric field. A global Lax–Friedrichs flux splitting scheme with a monotonic upwind scheme for conservation laws is used for the inviscid flux calculation. Moments of a shifted Maxwellian distribution that is constructed from the fluid quantities are taken to calculate fluxes at the boundaries, henceforth called the kinetic fluxes. Two full fluid moment models are developed based on the treatment of the electron energy: (i) the total energy and (ii) the internal energy, i.e., temperature. A DC low-temperature magnetized plasma in a Hall effect thruster is modeled using the full fluid moment model and the results are compared with drift-diffusion models that are commonly used for low-temperature plasmas, providing insights into nonclassical electron transport driven by the electron shear in cross-field devices.

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A model is developed for a collisionless plasma sheath assuming isentropic electrons in contrast to the standard isothermal electron assumption. This approach is enabled by the approximation of a Maxwellian electron velocity distribution function across the sheath, which is justified by near wall measurements. The conservation of entropy leads to a modified Boltzmann relation and a modified Bohm criterion. The predicted floating sheath potential is in excellent agreement with experimental data. Takamura's model for a space-charge limited plasma sheath near an emissive surface is also modified for isentropic electrons and with that modification agrees well with numerical results from a full fluid plasma model.