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This research aimed to evaluate spray humidifiers as evaporation processes. The tube in evaporation processes in this research was designed in the form of a venturi tube. Venturi tubes have been employed as devices for gas and liquid flow measurement using Bernoulli's theorem or differential pressure. Venturi tube equipment mainly consists of three sections. The first is a converging conical entrance, comprised of a convergent cone with a diameter of 30 centimeters. The second section is a cylindrical throat, which is a constant cross-sectional area region with a diameter of 9 centimeters. The third section is a diverging conical section consisting of a divergent cone. Increasing or decreasing cross-sectional area of a venturi tube affects fluid velocity and pressure inside such a tube. In this research, a set of spray nozzles in the first section at the inlet side of the venturi tube and two variables, distance between nozzles inside the venturi tube (Xs) as well as the angle between the nozzle and venturi tube (θ), were studied. According to relevant research studies, the angle of the nozzle installed in a venturi tube is commonly used in tests of the direction of gas flow. Absorption testing of fine particles or mixing between the liquid injected from the nozzle and the particles flowing into the tube should be homogeneous. Therefore, the angle of the test spray is usually set against the direction of gas flow. The angles to the venturi tubes were 30°, 60° and 90°. The distance between the two nozzles were 5, 10 and 15 cm from the center of the venturi tube, decreasing the temperature while increasing the relative humidity, humidifying performance, and the amount of evaporated water spray. The results of this research showed that spray water could decrease the temperature and increase the relative humidity. Furthermore, a nozzle distance of 15 cm from the center was the most effective distance between two nozzles with respect to increased relative humidity. Also, a 30° angle between the nozzle and venturi tube with a 15 cm distance between the nozzles resulted in the highest relative humidity as water spray contacted air entering the venturi tube over a wider area that increase humidification by water droplets. [ABSTRACT FROM AUTHOR]

This research studied the performance of a Micro Vertical Axis Savonius Wind Turbine with wind boosters. An S-shaped Micro Vertical Axis Savonius Wind Turbine was tested in a wind tunnel. Wind boosters were built in front of the turbine at different angles (10° to 90°) and numbers (2 to 6). The highest and lowest rotating speed, voltage, current, output power (electrical power), tip speed ratio and power coefficient were observed for 3 wind boosters at an angle of 80° and 5 wind boosters at 10°. The results indicate that the most suitable amount and angle of wind boosters for this research were 80° with 4 boosters because at a high wind booster angle (90°), the wind booster partially blocked the airflow and for the low wind booster angle, the wind boosters were almost parallel to the airflow and accelerated airflow speed was lower than the high wind booster angles. For the larger wind booster number, the wind booster partially blocked the airflow and, for the small wind booster number, the wind booster accelerated airflow speed, lower than the large wind booster number. The results from this research can be applied for the efficient performance of novel wind boosters for Micro Vertical Axis Savonius Wind Turbine designs, which will be beneficial for the use of wind energy. [ABSTRACT FROM AUTHOR]