Chen-Kang Huang - Academia.edu (original) (raw)

Papers by Chen-Kang Huang

Experimental Heat Transfer, 2009

2022 IEEE International Conference on Consumer Electronics - Taiwan

Abstract—This study experimentally and numerically investigates motor cooling performance. The mo... more Abstract—This study experimentally and numerically investigates motor cooling performance. The motor consists of a centrifugal fan, two axial fans, a shaft, a stator, a rotor and a heat exchanger with 637 cooling tubes. The pressure rise-flow rate (P-Q) performance curves of the cooling fans at 1800 rpm are tested using a test apparatus complying with the Chinese National Standard (CNS) 2726. Compared with the experimental measurements, the numerical analysis results show that the P-Q performance curves of the axial fan and centrifugal fan can be estimated within about 2 % and 6%, respectively. By using the simplified model, setting up the heat exchanger and stator as porous media, the flow field in the motor is calculated. By using the results of the flow field near the rotor and stator, and subjecting the heat generation rate as a boundary condition, the temperature distributions of the stator and rotor are also calculated. The simulation results show that the calculated temperatu...

2018 International Conference on System Science and Engineering (ICSSE), 2018

Mowing is the most fundamental practice to maintain lawn. However, this can be a monotonous, trou... more Mowing is the most fundamental practice to maintain lawn. However, this can be a monotonous, troublesome and dangerous work. It is so parlous that stones and twigs can be thrown out to the operator. It is quite difficult for person to focus during the entire period of time and tragedy can occur. Currently, the sweeping robots are quite common on the market. But, it is not so general to robotic lawn mower. Robotic lawn mower is based on computer vision and several path planning algorithms. In this work, robotic lawn mower is designed that it will run two times to finish its job. At the first round, Simultaneous Localization and Mapping (SLAM) algorithm is the main method to realize the map building, and mower also record the area which is unmown adequately via the camera on the rear of mower. At the second round, mower aims to the area has been marked and move to the area by A* Search and Depth First Search (DFS) to realize the shortest path planning. Therefore, it can perform the be...

For recent mobile devices, vapor chambers are excellent heat dissipation components to avoid hot ... more For recent mobile devices, vapor chambers are excellent heat dissipation components to avoid hot spots. However, the space for vapor chambers is less and less. In this study, a fabrication process specially designed for thin vapor chambers was proposed. The wick structure was then processed to integrate with vapor passages of various width or structured surface on the evaporation region. Thin vapor chambers with internal vapor core of 0.6 mm in thickness were focused. Vapor passage width of 2, 4, and 6 mm, as well as three structured surfaces on the evaporation region, were fabricated with the thermal performances explored. The thermal performances of the vapor chambers with and without the specific designs for the same thickness of the bulk copper block were compared. It is found that the vapor chamber with vapor passages width of 6 mm and an indented cross on the evaporation region shows the lowest thermal resistance of 0.186 K/W at the heat source supplied power of 100W. The prop...

2015 9th International Conference on Sensing Technology (ICST)

A capacitance sensor was designed to measure the water content in desiccant wheels. 24 AWG (Ameri... more A capacitance sensor was designed to measure the water content in desiccant wheels. 24 AWG (American wire gauge) single conductor wires were constructed to be the probe. Prototype sensors of two probe lengths inserted into the wheel and two numbers of wires were prepared. Four locations of the desiccant wheel were tested to verify if the measured trend is consistent with the weight variation and the physics sense. After series of tests on two desiccant wheels from different suppliers over the regeneration process, the variation of capacitance values is agreed with that of water content by weight measurement. It is believed that the capacitance is able to be a good indicator of water content, and the current design is economical and suitable to be a continuous online sensor. It will be very helpful to determine the end of dehumidification or regeneration process.

In this study, Leidenfrost experiments were conducted for water, Al2O3, and TiO2 (0.1% and 0.4%) ... more In this study, Leidenfrost experiments were conducted for water, Al2O3, and TiO2 (0.1% and 0.4%) nanofluids. In our tests, a 20 l test liquid is gently deposited on a horizontal heated aluminum surface. The evaporation time at various surface temperatures was recorded and plotted as evaporation curves. It is demonstrated that, for most nanofluids, the nanoparticles increase the Leidenfrost temperature and shorten the evaporation time. However, 0.1% TiO2 nanofluid exhibits a Leidenfrost temperature lower than that of pure water and a longer peak evaporation time. Some explanations of this interesting discovery are explored and accessed. The effects of nanoparticles on the surface tension of the nanofluid and the particle diffusion of the nanofluid are discussed.

International Journal of Automation and Smart Technology

This study introduces a novel inverse heat conduction problem (IHCP) calculation scheme to solve ... more This study introduces a novel inverse heat conduction problem (IHCP) calculation scheme to solve the surface heat flux of a subject with impinging cooling. From measured temperature records, the unknown boundary condition can be derived with one of three proposed algorithms. The scheme can then be performed without multiple iterations, and is much faster than traditional methods for IHCP. An impinging cooling apparatus is established to demonstrate the proposed scheme. The apparatus is to experimentally explore three impinging patterns, three impinging positions, and three unknown boundary condition derivation algorithms. The experimental results show that the proposed calculation scheme actually saves calculation time, and provides more accurate results. The most suitable unknown boundary condition derivation algorithm is suggested for each combination of operating parameters.

Advances in Technology Innovation

It is known that climate change causes a decrease in the profit gained from agricultural producti... more It is known that climate change causes a decrease in the profit gained from agricultural production. This work designs and establishes weather boxes equipped with functions of rainfall prediction, frosting forecast, and lightning detection. With the wireless connection and the build-in decision mode, weather boxes can deliver early-warning by sending texting messages to the users and actuating the corresponding action to response the extreme climate. To implement rainfall and frosting prognostication, two different datasets are analyzed by the technology of data mining. One of the datasets is acquired from the Central Weather Bureau, and the other is from the proposed weather box monitoring the agricultural environment. From the experimental results, the prediction model constructed from the data which is collected by the proposed weather box exhibits a higher accuracy in rainfall forecasting than those based on the Central Weather Bureau.

Renewable and Sustainable Energy Reviews

Proceeding of International Heat Transfer Conference 12

HortTechnology

Hydroponic systems in plant factories can be categorized into recirculating or noncirculating sys... more Hydroponic systems in plant factories can be categorized into recirculating or noncirculating systems. In this study, the effects of various commercially available circulation pumps, including a centrifugal magnetic drive pump, a regenerative self-priming pump, and a submersible pump, were experimentally explored. In addition, the effects of an ultraviolet sterilization system on the ion concentrations in nutrient solutions were examined. The concentrations of sodium, potassium, magnesium, calcium, nitrate, sulfate, and ferric (Fe3+) ions in the nutrient solution were measured. For all three types of pumps, the results indicated that there was no significant effect on the concentrations of ions in the nutrient solution. However, the concentration of Fe3+ ions decreased significantly after the nutrient solution was treated by a ultraviolet sterilization system for 48 hours. In addition, the effects of the three types of pumps on the growth of butterhead lettuce (Lactuca sativa) were ...

Renewable and Sustainable Energy Reviews

2009 4th International Microsystems, Packaging, Assembly and Circuits Technology Conference, 2009

ABSTRACT This study investigated using high power UV light emitting diode (LED) to replace the tr... more ABSTRACT This study investigated using high power UV light emitting diode (LED) to replace the traditional UV lamp in printed circuit board process. It was expected to take the advantages of energy conservation, long life and quick response of UV-LEDs. The feasibility of this replacement was evaluated. There were two kinds of light modules in this work; Type 1 composed of six 1-Watt UV-LEDs arranging as a circle of diameter in 50 mm. Type 2 was equipped with twelve 3-Watt LEDs soldered on a MCPCB of 100 mm in diameter. Both modules emitted a spectrum distribution peaking at a wavelength of 400 nm. The angle of view measuring apparatus was completed for measuring light module angle of view and UV intensity. In order to obtain collimated light source, the parabolic reflectors were used for Type 1. The reflectors showed the six to ten times enhancement of intensity and the improvement of the angle of view from 140° to 30°. In order to approach the practical process, only the original light source was replaced by UV-LED light modules. Other parameters on the automation system remained unchanged. After etching, the patterns were observed and measured by image measurement software. Following the PCB standards, only results with relative errors under 15% were accepted. At present, the minimum reproducible feature size is 75 ¿m by Type 2 light source with 50 mm or 100 mm distance between light source and mask. The results show the feasibility and potential usage of UV-LED in PCB lithography.

Biomicrofluidics, 2016

A microfluidic chip is proposed to separate microparticles using cross-flow filtration enhanced w... more A microfluidic chip is proposed to separate microparticles using cross-flow filtration enhanced with hydrodynamic focusing. By exploiting a buffer flow from the side, the microparticles in the sample flow are pushed on one side of the microchannels, lining up to pass through the filters. Meanwhile a larger pressure gradient in the filters is obtained to enhance separation efficiency. Compared with the traditional cross-flow filtration, our proposed mechanism has the buffer flow to create a moving virtual boundary for the sample flow to actively push all the particles to reach the filters for separation. It further allows higher flow rates. The device only requires soft lithograph fabrication to create microchannels and a novel pressurized bonding technique to make high-aspect-ratio filtration structures. A mixture of polystyrene microparticles with 2.7 μm and 10.6 μm diameters are successfully separated. 96.2 ± 2.8% of the large particle are recovered with a purity of 97.9 ± 0.5%, while 97.5 ± 0.4% of the small particle are depleted with a purity of 99.2 ± 0.4% at a sample throughput of 10 μl/min. The experiment is also conducted to show the feasibility of this mechanism to separate biological cells with the sample solutions of spiked PC3 cells in whole blood. By virtue of its high separation efficiency, our device offers a label-free separation technique and potential integration with other components, thereby serving as a promising tool for continuous cell filtration and analysis applications.

Numerous methods, such as sintered or machined surface, have been proposed to enhance the boiling... more Numerous methods, such as sintered or machined surface, have been proposed to enhance the boiling performance. On the other hand, nanofluids are also reported to increase the convective heat transfer and become attractive in many engineering applications. In this study, anodizing was tried to produce porous structure on the heater surface to enhance the boiling performance. Two electrolyes, phosphoric acid and oxalic acid, were used. It was found the anodized pores prepared by oxalic acid were smaller. However, the phosphoric acid anodized surface exhibited a CHF increment by 40% with almost no superheat increment. A nanofluid pre-boiling process was also proposed. An aluminum wire was used as the heater to boil nanofluid for a certain time at a certain heat flux. 0.1 wt% TiO2 nanofluid was used as the working fluid during the pre-boiling process. The wire then went on being the heater for pure water. It is found that aluminum wires exhibit boiling enhancement after preboiling in na...

This study experimentally and numerically investigates motor cooling performance. The motor consi... more This study experimentally and numerically investigates motor cooling performance. The motor consists of a centrifugal fan, two axial fans, a shaft, a stator, a rotor and a heat exchanger with 637 cooling tubes. The pressure rise-flow rate (P-Q) performance curves of the cooling fans at 1800 rpm are tested using a test apparatus complying with the Chinese National Standard (CNS) 2726. Compared with the experimental measurements, the numerical analysis results show that the P-Q performance curves of the axial fan and centrifugal fan can be estimated within about 2% and 6%, respectively. By using the simplified model, setting up the heat exchanger and stator as porous media, the flow field in the motor is calculated. By using the results of the flow field near the rotor and stator, and subjecting the heat generation rate as a boundary condition, the temperature distributions of the stator and rotor are also calculated. The simulation results show that the calculated temperature of the ...

Experimental Heat Transfer, 2009

2022 IEEE International Conference on Consumer Electronics - Taiwan

Abstract—This study experimentally and numerically investigates motor cooling performance. The mo... more Abstract—This study experimentally and numerically investigates motor cooling performance. The motor consists of a centrifugal fan, two axial fans, a shaft, a stator, a rotor and a heat exchanger with 637 cooling tubes. The pressure rise-flow rate (P-Q) performance curves of the cooling fans at 1800 rpm are tested using a test apparatus complying with the Chinese National Standard (CNS) 2726. Compared with the experimental measurements, the numerical analysis results show that the P-Q performance curves of the axial fan and centrifugal fan can be estimated within about 2 % and 6%, respectively. By using the simplified model, setting up the heat exchanger and stator as porous media, the flow field in the motor is calculated. By using the results of the flow field near the rotor and stator, and subjecting the heat generation rate as a boundary condition, the temperature distributions of the stator and rotor are also calculated. The simulation results show that the calculated temperatu...

2018 International Conference on System Science and Engineering (ICSSE), 2018

Mowing is the most fundamental practice to maintain lawn. However, this can be a monotonous, trou... more Mowing is the most fundamental practice to maintain lawn. However, this can be a monotonous, troublesome and dangerous work. It is so parlous that stones and twigs can be thrown out to the operator. It is quite difficult for person to focus during the entire period of time and tragedy can occur. Currently, the sweeping robots are quite common on the market. But, it is not so general to robotic lawn mower. Robotic lawn mower is based on computer vision and several path planning algorithms. In this work, robotic lawn mower is designed that it will run two times to finish its job. At the first round, Simultaneous Localization and Mapping (SLAM) algorithm is the main method to realize the map building, and mower also record the area which is unmown adequately via the camera on the rear of mower. At the second round, mower aims to the area has been marked and move to the area by A* Search and Depth First Search (DFS) to realize the shortest path planning. Therefore, it can perform the be...

For recent mobile devices, vapor chambers are excellent heat dissipation components to avoid hot ... more For recent mobile devices, vapor chambers are excellent heat dissipation components to avoid hot spots. However, the space for vapor chambers is less and less. In this study, a fabrication process specially designed for thin vapor chambers was proposed. The wick structure was then processed to integrate with vapor passages of various width or structured surface on the evaporation region. Thin vapor chambers with internal vapor core of 0.6 mm in thickness were focused. Vapor passage width of 2, 4, and 6 mm, as well as three structured surfaces on the evaporation region, were fabricated with the thermal performances explored. The thermal performances of the vapor chambers with and without the specific designs for the same thickness of the bulk copper block were compared. It is found that the vapor chamber with vapor passages width of 6 mm and an indented cross on the evaporation region shows the lowest thermal resistance of 0.186 K/W at the heat source supplied power of 100W. The prop...

2015 9th International Conference on Sensing Technology (ICST)

A capacitance sensor was designed to measure the water content in desiccant wheels. 24 AWG (Ameri... more A capacitance sensor was designed to measure the water content in desiccant wheels. 24 AWG (American wire gauge) single conductor wires were constructed to be the probe. Prototype sensors of two probe lengths inserted into the wheel and two numbers of wires were prepared. Four locations of the desiccant wheel were tested to verify if the measured trend is consistent with the weight variation and the physics sense. After series of tests on two desiccant wheels from different suppliers over the regeneration process, the variation of capacitance values is agreed with that of water content by weight measurement. It is believed that the capacitance is able to be a good indicator of water content, and the current design is economical and suitable to be a continuous online sensor. It will be very helpful to determine the end of dehumidification or regeneration process.

In this study, Leidenfrost experiments were conducted for water, Al2O3, and TiO2 (0.1% and 0.4%) ... more In this study, Leidenfrost experiments were conducted for water, Al2O3, and TiO2 (0.1% and 0.4%) nanofluids. In our tests, a 20 l test liquid is gently deposited on a horizontal heated aluminum surface. The evaporation time at various surface temperatures was recorded and plotted as evaporation curves. It is demonstrated that, for most nanofluids, the nanoparticles increase the Leidenfrost temperature and shorten the evaporation time. However, 0.1% TiO2 nanofluid exhibits a Leidenfrost temperature lower than that of pure water and a longer peak evaporation time. Some explanations of this interesting discovery are explored and accessed. The effects of nanoparticles on the surface tension of the nanofluid and the particle diffusion of the nanofluid are discussed.

International Journal of Automation and Smart Technology

This study introduces a novel inverse heat conduction problem (IHCP) calculation scheme to solve ... more This study introduces a novel inverse heat conduction problem (IHCP) calculation scheme to solve the surface heat flux of a subject with impinging cooling. From measured temperature records, the unknown boundary condition can be derived with one of three proposed algorithms. The scheme can then be performed without multiple iterations, and is much faster than traditional methods for IHCP. An impinging cooling apparatus is established to demonstrate the proposed scheme. The apparatus is to experimentally explore three impinging patterns, three impinging positions, and three unknown boundary condition derivation algorithms. The experimental results show that the proposed calculation scheme actually saves calculation time, and provides more accurate results. The most suitable unknown boundary condition derivation algorithm is suggested for each combination of operating parameters.

Advances in Technology Innovation

It is known that climate change causes a decrease in the profit gained from agricultural producti... more It is known that climate change causes a decrease in the profit gained from agricultural production. This work designs and establishes weather boxes equipped with functions of rainfall prediction, frosting forecast, and lightning detection. With the wireless connection and the build-in decision mode, weather boxes can deliver early-warning by sending texting messages to the users and actuating the corresponding action to response the extreme climate. To implement rainfall and frosting prognostication, two different datasets are analyzed by the technology of data mining. One of the datasets is acquired from the Central Weather Bureau, and the other is from the proposed weather box monitoring the agricultural environment. From the experimental results, the prediction model constructed from the data which is collected by the proposed weather box exhibits a higher accuracy in rainfall forecasting than those based on the Central Weather Bureau.

Renewable and Sustainable Energy Reviews

Proceeding of International Heat Transfer Conference 12

HortTechnology

Hydroponic systems in plant factories can be categorized into recirculating or noncirculating sys... more Hydroponic systems in plant factories can be categorized into recirculating or noncirculating systems. In this study, the effects of various commercially available circulation pumps, including a centrifugal magnetic drive pump, a regenerative self-priming pump, and a submersible pump, were experimentally explored. In addition, the effects of an ultraviolet sterilization system on the ion concentrations in nutrient solutions were examined. The concentrations of sodium, potassium, magnesium, calcium, nitrate, sulfate, and ferric (Fe3+) ions in the nutrient solution were measured. For all three types of pumps, the results indicated that there was no significant effect on the concentrations of ions in the nutrient solution. However, the concentration of Fe3+ ions decreased significantly after the nutrient solution was treated by a ultraviolet sterilization system for 48 hours. In addition, the effects of the three types of pumps on the growth of butterhead lettuce (Lactuca sativa) were ...

Renewable and Sustainable Energy Reviews

2009 4th International Microsystems, Packaging, Assembly and Circuits Technology Conference, 2009

ABSTRACT This study investigated using high power UV light emitting diode (LED) to replace the tr... more ABSTRACT This study investigated using high power UV light emitting diode (LED) to replace the traditional UV lamp in printed circuit board process. It was expected to take the advantages of energy conservation, long life and quick response of UV-LEDs. The feasibility of this replacement was evaluated. There were two kinds of light modules in this work; Type 1 composed of six 1-Watt UV-LEDs arranging as a circle of diameter in 50 mm. Type 2 was equipped with twelve 3-Watt LEDs soldered on a MCPCB of 100 mm in diameter. Both modules emitted a spectrum distribution peaking at a wavelength of 400 nm. The angle of view measuring apparatus was completed for measuring light module angle of view and UV intensity. In order to obtain collimated light source, the parabolic reflectors were used for Type 1. The reflectors showed the six to ten times enhancement of intensity and the improvement of the angle of view from 140° to 30°. In order to approach the practical process, only the original light source was replaced by UV-LED light modules. Other parameters on the automation system remained unchanged. After etching, the patterns were observed and measured by image measurement software. Following the PCB standards, only results with relative errors under 15% were accepted. At present, the minimum reproducible feature size is 75 ¿m by Type 2 light source with 50 mm or 100 mm distance between light source and mask. The results show the feasibility and potential usage of UV-LED in PCB lithography.

Biomicrofluidics, 2016

A microfluidic chip is proposed to separate microparticles using cross-flow filtration enhanced w... more A microfluidic chip is proposed to separate microparticles using cross-flow filtration enhanced with hydrodynamic focusing. By exploiting a buffer flow from the side, the microparticles in the sample flow are pushed on one side of the microchannels, lining up to pass through the filters. Meanwhile a larger pressure gradient in the filters is obtained to enhance separation efficiency. Compared with the traditional cross-flow filtration, our proposed mechanism has the buffer flow to create a moving virtual boundary for the sample flow to actively push all the particles to reach the filters for separation. It further allows higher flow rates. The device only requires soft lithograph fabrication to create microchannels and a novel pressurized bonding technique to make high-aspect-ratio filtration structures. A mixture of polystyrene microparticles with 2.7 μm and 10.6 μm diameters are successfully separated. 96.2 ± 2.8% of the large particle are recovered with a purity of 97.9 ± 0.5%, while 97.5 ± 0.4% of the small particle are depleted with a purity of 99.2 ± 0.4% at a sample throughput of 10 μl/min. The experiment is also conducted to show the feasibility of this mechanism to separate biological cells with the sample solutions of spiked PC3 cells in whole blood. By virtue of its high separation efficiency, our device offers a label-free separation technique and potential integration with other components, thereby serving as a promising tool for continuous cell filtration and analysis applications.

Numerous methods, such as sintered or machined surface, have been proposed to enhance the boiling... more Numerous methods, such as sintered or machined surface, have been proposed to enhance the boiling performance. On the other hand, nanofluids are also reported to increase the convective heat transfer and become attractive in many engineering applications. In this study, anodizing was tried to produce porous structure on the heater surface to enhance the boiling performance. Two electrolyes, phosphoric acid and oxalic acid, were used. It was found the anodized pores prepared by oxalic acid were smaller. However, the phosphoric acid anodized surface exhibited a CHF increment by 40% with almost no superheat increment. A nanofluid pre-boiling process was also proposed. An aluminum wire was used as the heater to boil nanofluid for a certain time at a certain heat flux. 0.1 wt% TiO2 nanofluid was used as the working fluid during the pre-boiling process. The wire then went on being the heater for pure water. It is found that aluminum wires exhibit boiling enhancement after preboiling in na...

This study experimentally and numerically investigates motor cooling performance. The motor consi... more This study experimentally and numerically investigates motor cooling performance. The motor consists of a centrifugal fan, two axial fans, a shaft, a stator, a rotor and a heat exchanger with 637 cooling tubes. The pressure rise-flow rate (P-Q) performance curves of the cooling fans at 1800 rpm are tested using a test apparatus complying with the Chinese National Standard (CNS) 2726. Compared with the experimental measurements, the numerical analysis results show that the P-Q performance curves of the axial fan and centrifugal fan can be estimated within about 2% and 6%, respectively. By using the simplified model, setting up the heat exchanger and stator as porous media, the flow field in the motor is calculated. By using the results of the flow field near the rotor and stator, and subjecting the heat generation rate as a boundary condition, the temperature distributions of the stator and rotor are also calculated. The simulation results show that the calculated temperature of the ...