چكيده به لاتين
Due to unique characteristics and various applications, synthetic jets have always been a notable subject for researchers and have dedicated a lot of numerical and experimental studies to themselves. One of the most prominent features of synthetic jet, is the fact that no injection of external fluid is required. Therefore, it can be applied for cooling in places where the injection of fluid is not possible. In comparison to forced convection with conventional methods, synthetic jets demonstrate a more effective cooling performance. Due to the complex nature of turbulence flow, selecting appropriate turbulence model is considered of high importance. The majority of the studies in this field are done with URANS models. In previous studies conducted in heat transfer laboratory of IUST, the behavior of synthetic jet in presence of cross flow is investigated with URANS and LES models. The purpose of this thesis is to investigate the ability of DES and SAS models since they have lower computational complexity compared to LES and DNS and are more precise in comparison to URANS models to simulate the problem. Initially, after the simulation and validation of the problem with kw/sst , SAS and DES models, the results of simulation is compared to existing experimental results. All of the mentioned models have failed to accurately predict the heat transfer coefficient in downstream of the target plate. Later, the effect of contributing parameters, i.e., frequency of synthetic jet and the velocity of cross flow are studied in the problem. The results seem to suggest that there is an optimum value of cross flow velocity in which the heat transfer of the synthetic jet is maximized. In the last part of the thesis, the role of a new parameter known as K which indicates the ratio of suction time to blowing time, is assessed. The optimum value of heat transfer coefficient has an inverse ratio with the parameter K, therefore it decreases as the parameter K increases. On the other hand, with higher values of K, the distribution of heat transfer coefficient on the target plate becomes more uniform.
