Papers by Author: Ching Song Jwo

Abstract: This study developed an oxygenase system with horizontal-axis wind turbine driving the oxygenation device by belt pulley for aquaculture, and verified the feasibility of the system in conditions of Taiwan’s average wind speed. The experimental system is consisted of a horizontal wind turbine, a reciprocating compressor, and water channels. At the first stage of the experiment, the reciprocating compressor oxygenase system was measured according to the power supply standards in terms of power consumption, air displacement and oxygen production, in case of various rotating speeds and the compliance with aquaculture standards. At the second stage of the experiment, the wind turbine was used to directly drive the reciprocating compressor oxygenase system. According to the experimental results, regarding the test of the compressor oxygenase system, when power supply rotating speed is 406.7 rpm, power consumption is 234.5 W and the oxygen production is 7.48mg/L, which is above the level of amount of dissolved oxygen of aquaculture at 5.5mg/L. In case of driving the oxygenation device by wind power, when wind speed is 5.06 m/s and the wind turbine rotating speed is 140 rpm, the average dissolved oxygen in the water is 5.9 mg/L, which meets the aquaculture standards. Even in case of unstable wind speed, good oxygen production effects can be achieved. Moreover, the system is directly driven by wind power and does not require electric power.

Abstract: This study discussed the feasibility of developing a system to circulate the heat loss from the coil and iron core of the power transformer equipped for buildings during power supply to the heat recovery unit. This study affixed a copper tube into the transformer insulating oil, allowing the water to circulate at normal temperature in the coil tube, and absorb the heat energy generated by the transformer coil and iron core. The heat energy was then recovered and stored. A low tension power transformer (7.5 KV) was used in the experiment. The operation was carried out in transforming power supply mode to seek for the most suitable recovery unit for various occasions. The test results showed that if the hot water recovery efficiency is 50%, in the course of producing hot water, the mean temperature of 17.5 L normal temperature water can be increased from 20°C to 50°C, thus producing 12.5 kJ heat only spends about 34 min. The results proved that the recovery unit for the heat from the power transformer can benefit from heating, prolong the transformer's lifetime, increase the power supply efficiency, and reduce the air conditioning load to save energy and to reduce global warming.

Abstract: This study aims to investigate energy saving efficiency of condensing heat recovery device installed in constant temperature/humidity system. In the experiment, heat tank (heat exchanger) firstly stores condensing heat, which replaces the role of electric reheating method in traditional constant temperature/humidity system. And then the study discusses the effect of reheating methods, electric heating and heat recovery, on temperature, relative humidity, and electricity consumption in the constant temperature/humidity system. The experimental result shows that the heat recovery device exerts better control on temperature and relative humidity under differential room loads. And by providing additional power dissipation for the water pump and the fan only, it meets the requirement of reheat supply. As a result, overall power consumption of the constant temperature/humidity system reduces by 22.5-38.2%. This study uses the reheat recycled through condensing heat recovery and supplied to the constant temperature/humidity air-conditioning equipment, and indeed reduces electricity consumption of the overall constant temperature/humidity system and maintains a stable temperature and humidity environment.

Abstract: This study developed a set of equipment that can measure the treadmill exercise energy consumption accurately, and apply the exercise energy consumption to refrigeration and heating devices, thus supplying hot water and chilled water for users. Exercise energy consumption is conventionally measured based on the amount of exercise, but this study used non-electric mode to drive refrigeration and heating devices. According to the measurement results, the heat energy generated by exercise energy is 65 kcal; as compared with the 70 kcal measured by calorie meter, the result is within 10% of error range, thus proving that the proposed measuring method is worth research and development. In addition, without conventional energy sources, 3,000c.c of hot water (45°C) and 1,500c.c of cold water (7°C) could be generated within 20min use of the treadmill. The proposed equipment can measure the exercise energy consumption, and support the refrigeration and heating system to produce free hot water and cold water. This is an environmentally-friendly and innovative multifunctional equipment worthy of further research and development .

Abstract: This paper presents the development of a conductive composite film and the measurement of electromagnetic (EM) shielding effectiveness (SE) of the prepared film. A coaxial transmission-line technique based on ASTM D4935-99 Standard was used to measure the electromagnetic shielding effectiveness. A nickel nanofluid with an average particle size of 50 nm was prepared with a self-developed nanofluid synthesis system. By using a polymer blending method, carbon fiber and carbon fiber/nickel nanoparticles were blended with waterborne polyurethane (WPU) to prepare conductive composite films of 0.25 mm thick. Experimental results have shown that the electromagnetic shielding effectiveness value of the prepared conductive composite material can reach 26 dB within the range of 50 MHz ~ 1.5GHz.

Abstract: This study develops a measurement method for testing the efficiency of photocatalysts in the degradation of NH3 gaseous concentrations. The catalysts used in this study are the same as those used previously in our UV/VIS spectrophotometer. Reaction measurements were carried out at 27°C and 17°C under ambient pressure on Heat Ventilating and Air Conditioning (HVAC) system. Quartz plates were coated with TiO2 nanocatalyst. Then the plate was put in the stable reaction cell under different flow rates of circulation. The experiment gives a direct and simple measurement of ammonia flux and hence of overall ammonia emission rate. The results reveal that the Submerged Arc Nanoparticle Synthesis System (SANSS) TiO2 nanocatalyst has excellent degradation efficiency towards NH3, so that when it is exposed to UV irradiation for 60 minutes, the gaseous concentration can be reduced to 10% of the original concentration. In addition, the rate constant of the degradation reaction of the self-made TiO2 nanocatalyst towards NH3 is as high as 0.039min-1.

Abstract: This study used the Al2O3 nano-lubricant produced from the direct synthesis method was used as the experimental samples and the ultrasonic vibration was used for dispersing the nanoparticles into three types of the weight fraction (0.1, 0.2, 0.3%wt). The base solvent was the lubricant of vacuum pump. The objectives of this study were to discuss the dependence of operating temperature of vacuum pump under the various weight fraction of Al2O3 nanoparticles. In this experiment we added Al2O3 nano-lubricant into the direct drive oil sealed rotary vacuum pump, and used the thermocouple measure the temperature on the four test points (cylinder, in-lubricant, case of vacuum pump and discharge pipeline). The results show that the cylinder temperature was reduced by 1.3% and increased by 0.4%, 1.8%, the lubricant temperature was increased by 5.3%, 0.5% and 1.9%, the case surface temperature was reduced by 1.7%, 1.4% and 1.5%, and discharge pipeline temperature was reduced by 0.6%, 2.1% and 3.8% respectively when the sample fractions were 0.1%, 0.2% and 0.3%wt. From the results, it could be realized that the nano-lubricant has more effects on increasing the performance of heat sink than conventional lubricant.

Abstract: This paper describes an innovative system to produce nanoparticles based on the theory of gas condensation in producing nanoparticles. In a vaccuum environment, the system used the energy produced by high frequency induction to vaporize a pure zinc rod inside the crucible. During the vaporization the chamber was filled with He gas, so the high-temperatured vaporized metal can undergo momentum exchange with He gas and at the same time, induce the vaporized metal to move to the cold trap. Upon reaching the wall of the cold condenser, the vaporized metal instantly condensed, forming nanoparticles. The TEM image shows that their average diameter was 30 nm, and the size was very consistent. In addition, the Zeta potential and average diameter of the ZnO nanofluid was also measured under different pH conditions to determine the stability of the ZnO nanofluid. Moreover, in order to verify the practicability of the fabricated ZnO nanoparticles, the ZnO nanofluid was inspected by UV/Vis absorption spectrum, and the results show that ZnO nanoparticles absorption ability was within a wavelength range from 350nm to 550nm.

Abstract: This research carries out an inexpensive, rapid and novel exercise, which is applied to perform the photocatalyst decomposition effectiveness of Methanol and Ethanol in gaseous form. The major devices of this applicable measurement developed by this practice are only utilizing ultraviolet-visible spectrophotometer and quartz cuvette, and the experimental procedures are straightforward and speedy. In the conduct experiments, Methanol and Ethanol with a specific concentration is initially injected into an enclosed quartz cuvette. Then the cuvette is put in ultraviolet- visible spectrophotometer to measure the Methanol and Ethanol concentration, so as to obtain an unique UV absorbance spectrum at its particular concentration. In the conduct experiments of measuring photocatalyst decomposition efficiency, the self-made (SANSS) nanocatalyst TiO2 is initially coated in the quartz plate, and put into the quartz. Then a specific concentration of methanol alcohol and ethanol is injected into the quartz cuvette under the UV irradiation exposure, so as to carry out photodecomposition of Methanol and Ethanol experiment. After that, the cuvettes are then put into the ultraviolet-visible spectrophotometer for measuring the absorbance intensity of UV spectrums in order to produce degradation chart. The preliminary results point out that the self-made nanocatalyst TiO2 has exceptionally outstanding decomposition efficiency which further points out the fact that, when UV irradiation for 60minutes, the gaseous Methanol can be reduced to 3.8% of the original sample, and the gaseous Ethanol can be reduced to 6% of the original sample. But when exercising with commercial nanocatalyst TiO2 to undergo the same process exactly under the same circumstances, the residue gaseous concentration can only be reduced to 17% and 16% of the gaseous Methanol and Ethanol original sample.