Engineering Applications of Computational Fluid Mechanics

If the actuator of the plasma synthetic jet (PSJ) operates continuously under a high frequency, the performance of the actuator will become worse than it is in single pulse test. This is because the air in the cavity cannot fully recover to the original state before the next cycle starts. Therefore, the characteristics of the plasma synthetic jet during continuous operation, rather than during a single pulse, need to be studied carefully. In this paper, simulated flow fields of the continuously working PSJ are analyzed. It is found that the time-averaged results of the PSJ are self-similar, however, the instantaneous results are only self-similar when y is less than y0.5. Moreover, the effects of the dominant parameters, such as the maximum temperature, cavity shape and the operating frequency, on the performance of the PSJ actuator under stable operating condition are discussed. The maximum temperature is the most important parameter for the PSJ actuator. Actuator performance improves when the maximum temperature increases. In contrast, the frequency has little influence on performance, and the PSJ actuator is shown to perform well under a wide range of frequencies. This is more beneficial for active flow control compared with the synthetic jet actuator driven by the piezoelectric patch. The shape and the volume of the cavity can also influence the performance of the actuator. As the volume of the cavity becomes smaller, the duration of the spurt period is reduced.