Modeling of fluid dynamics and the associated heat transfer induced by plasma between two parallel electrodes is investigated. In particular, we consider a capacitvely coupled radio frequency discharge plasma generator, where the plasma is generated on the surface of a dielectric circuit board with electrode strips on the top and bottom. The electrodes have a thickness of 100 μm, which is comparable to the height of the boundary layer. The regime considered is that the electron component is in the non-equilibrium state, and the plasma is nonthermal. Overall, due to the ion and large fluid particle interaction, the pressure is higher in the downstream of the electrode, causing the velocity structure to resemble that of a wall jet. Parameters related to the electrode operation, including the voltage, frequency, and free stream speed are varied to investigate the characteristics of the plasma-induced flow. Consistent with the experimental observation, the model shows a clear dependence of the induced jet velocity on the applied voltage and frequency. The heat flux exhibited a similar dependence on the strength of the plasma. The present plasma-induced flow concept can be useful for thermal management and active flow control.

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Glow discharge at atmospheric pressure using a dielectric barrier discharge can induce fluid flow, and operate as an actuator for flow control. In this paper, we simulate the physics of a 2-D asymmetric actuator operating in Helium gas using a high-fidelity first principles-based numerical modeling approach to help improve our understanding of the physical mechanisms associated with such actuators. Fundamentally, there are two processes in the two half-cycles of the actuator operation, largely due to the difference in mobility between faster electrons and slower ions, and the geometric configurations of the DBD/electrodes. The first half-cycle is characterized by the deposition of the slower ion species on the insulator surface while the second half-cycle by the deposition of the electrons at a faster rate. A power-law (cubic) dependence on the voltage for the resulting force is observed, which indicates that larger force can be generated by increasing the amplitude. Furthermore, one can enhance the effectiveness of the actuator, by either increasing the peak value of the periodic force generation or by increasing the asymmetry between the voltage half-cycles or both. Overall, the increase in the lower electrode size, applied voltage and dielectric constant tends to contribute to the first factor, and the decrease in frequency of applied voltage tends to contribute to the second factor. However, the complex interplay between the above factors determines the actuator performance.

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