Budi Kristiawan

Effect of Blade Curvature Angle of Savonius Horizontal Axis Water Turbine to the Power Generation

The water energy is one of potential alternative in creating power generation specifically for the picohydro energy. Savonius is a kind of wind turbine which now proposed to be operated utilizing the energy from low fluid flow. Researches about the utilization of Savonius turbine have been developed in the horizontal water pipelines and wave. The testing experimental on the Savonius Horizontal Axis Water Turbine (HAWT) by observing the effect of the blade curvature angle (ψ) of 110°, 120°, 130°, and 140° at the debit of 176.4 lpm, 345 lpm, 489.6 lpm, and 714 lpm in order to know the power output was already conducted. The optimal result in every debit variation was obtained in the blade curvature angle of 120°. In the maximum debit of 714 lpm with blade curvature angle of 120° the power output is 39.15 Watt with the coefficient power (Cp) of 0.23 and tip speed ratio (TSR) of 1.075.

The Effect of Deflector Angle in Savonius Water Turbine with Horizontal Axis on the Power Output of Water Flow in Pipe

Savonius turbine is one type of turbines with simple design and low manufacture. However, this turbine has a relatively low efficiency. This condition can be solved by installing fluid deflectors in the systems circuit. The deflector is used to direct the focus of the water flow, thus increasing the torque working moment. In this study, a single stage horizontal axis Savonius water turbine was installed on a 3 inch diameter pipeline. This experiment aims to obtain optimal deflector angle design on each water discharge level. The deflector performance is analyzed through power output, TSR, and power coefficient generated by the turbine. The deflector angles tested are without deflector, 20°, 30°, 40°, and 50° with a deflector ratio of 50%. The experimental results at 10.67x10−3m3/s discharge show that turbine equipped with 30° deflector has the most optimal performance of 18.04 Watt power output, TSR of 1.12 and power coefficient 0.127. While with the same discharge, turbine without deflector produces only 9.77 Watt power output, TSR of 0.93, and power coefficient of 0.09. Thus, it can be concluded that the deflector increases power output equal to 85%.

Fabrication and integration of PDMS-glass based microfluidic with optical absorbance measurement device for coliform bacteria detection

The detection of coliform bacteria which contain the disease-causing microorganism is a useful indication for water contamination. Currently, the emerging of technology in molecular biology research and industry is in demand for portable and miniaturized system. This paper demonstrates the development and integration of microfluidic and optical absorbance measurement device for portable coliform bacteria detection. The microfluidic device was fabricated with glass and polydimethylsiloxane (PDMS) material using photolithography, replica molding (soft lithography), and oxygen plasma bonding techniques. Then, the optical absorbance measurement device for coliform bacteria detection was developed using 470 nm blue light emitting diode (LED), photo detector, ARDUINO microcontroller, liquid crystal display (LCD), and mechanical elements. The coliform bacteria suspension sample was inserted into the microfluidic device and the presence of coliform bacteria was analyzed using the developed optical absorbance measurement device. The absorbance measurement from the prototype and colony number of the coliform bacteria samples were collected and analyzed. The final analysis had indicated that the developed prototype was able to detect the coliform bacteria in suspension at the lowest detection of 17,200 CFU/ml.