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Control of flow separation is a great issue to deal with a moving body to ensure its proper aerodynamic characteristics. To achieve this, various methods including active and passive control are suggested depends upon the flow characteristics and the surface in which control is necessary. To make the better use of both active and passive method of flow control this article proposed a new type of Double Sided Plasma Actuator (DSPVG) to overcome the drag penalty of conventional vortex generators (VGs) that commonly used in controlling flow and to use actively control. In this regard, the effectiveness of DSPVG has been numerically and experimentally investigated in a separated flow region of a 20 diffuser of an open type tunnel. DSPVG is placed at the upstream of separation location normal to the surface as like as conventional VG except zero angle with flow direction. Both numerical and experimental results of DSPVG are compared with that of VG and baseline flow and better agreements are found. Moreover, DSPVG has shown better separation supression ability than conventional VGs due to its dual vortices. It is found that DSPVG significantly delay the separation. A freestream flow of 4 m/s is used for experiments and numerical computations.

In hot climatic regions, some kind of cooling system is necessary to avoid warmth and humidity. Many of the available cooling systems are not economic and sustainable. In this study, sustainable and feasible space/room cooling systems have been experimentally analyzed. A solar operated cooling system with two options have been designed and their performances are compared. Phase Change Material (PCM) is proposed to store thermal energy instead of a costly battery. A 1200-watt compressor and fin-type condenser are used to construct the vapor compression system. When the incoming air is passed through the cooling coil, it gets cool. For this cooling coil, 50 feet copper tube is used. The front side copper tube diameter of the fan is 3/8 inch and the backside tube diameter is 1/2 inch. It took about 35 minutes and 5 minutes to minimize the room temperature at the desired level in the case of the stand fan and duct fan, respectively. Furthermore, the stand fan and duct fan systems reduced 3 ℃ and 6 ℃ of the outside temperature, respectively.

Flow control is an important issue in fluid mechanics and aerodynamics as separated flow introduce undesirable impact on overall system performance. Several active and passive techniques have been used to control the flow when necessary. But in passive control techniques, the actuator has to be fixed on the surface so that it can create vortices along streamline to enhance the mixing in the separated region to delay or suppress separation. Among passive flow control system vortex generators (VGs) are generally used but it control the flow with the cost of drag increase. It would be advantageous by combining both active and passive flow techniques together. In this regard plasma actuator (PA, active flow control device) and VGs are combined together with a view to not only suppress the separation but also minimizing the drag that could arise by using conventional passive control techniques. The combination flow control device is named as Plasma Vortex Generator (PVG) which proves its effectiveness to control separation as conventional VGs do but without any drag penalty.