Browsing by Author "Hsu, Wen-Syang"

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An integrated CFD and experimental study of the in-line fan
(2014)
Yen, Hung-Cheng
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Hsu, Wen-Syang
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Cheng, Yung-Jen
;
Lin, Sheam-Chyun
;
Wu, Yu-Chuan
This study analyzes the flow flied and the guide vane associated with an in-line fan by an integrated numerical and experimental investigation. At first, the flow field associated with the fan is simulated by using a commercial CFD code Fluent with the finite volume method. In addition, the guiding vane profile is imposed and modified by examining characteristics of flow field. An appropriate guiding vane with high-performance and low-noise feature can be achieved after several design iterations. To manufacture the mock-up for experimental verification, the designed fan is expressed in the CAD/CAM format for the rapid-prototype technique. Moreover, a set of relations correlating the performance and noise of this fan prototype are executed with the aids of AMCA test chamber and semi-anechoic chamber, respectively. Consequently, the feasibility of design scheme and numerical system can be verified according to these experimental results. In summary, this work provides a systematic scheme for designing and analyzing the in-line fan.
Development of a High Efficiency In-Line Tube Fan Using CFD
(2015-04-01)
Yen, Hung-Cheng
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Hsu, Wen-Syang
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Huang, Jeng-Min
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Lu, Chi-Wen
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Hsu, Chin-Nan
An in-line tube fan with design flow rate 1 m(3)/s, static pressure 1030 Pa, rotation speed 3450 rpm, and specific speed 2.1 was investigated. Inverse design method was used to design deswirl vane while CFD to analyze its flow field. Results showed that although the efficiency of the axial straight flat plate is poor, it remained better than that of the vaneless type. The efficiency of deswirl vane was much higher than the previous two. However, when the casing-impeller ratio was lower than 1.25, completely recovering tangential velocity would result in large recirculation flow near outlet of deswirl vane. When the casing-impeller ratio increased to 1.33, the recirculation flow and pressure loss were obviously reduced. When the casing-impeller ratio increased to 1.46, the deswirl vane almost completely recovered tangential velocity, and pressure loss was further reduced. Static pressure and efficiency at operating point were 10% and 6% higher than the casing-impeller ratio 1.33.
Digital Microfluidic Dynamic Culture of Mammalian Embryos on an Electrowetting on Dielectric (EWOD) Chip
(2015-05-01)
Huang, Hong-Yuan
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Shen, Hsien-Hua
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Tien, Chang-Hung
;
Li, Chin-Jung
;
Fan, Shih-Kang
Current human fertilization in vitro (IVF) bypasses the female oviduct and manually inseminates, fertilizes and cultivates embryos in a static microdrop containing appropriate chemical compounds. A microfluidic microchannel system for IVF is considered to provide an improved in-vivo-mimicking environment to enhance the development in a culture system for an embryo before implantation. We demonstrate a novel digitalized microfluidic device powered with electrowetting on a dielectric (EWOD) to culture an embryo in vitro in a single droplet in a microfluidic environment to mimic the environment in vivo for development of the embryo and to culture the embryos with good development and live births. Our results show that the dynamic culture powered with EWOD can manipulate a single droplet containing one mouse embryo and culture to the blastocyst stage. The rate of embryo cleavage to a hatching blastocyst with a dynamic culture is significantly greater than that with a traditional static culture (p<0.05). The EWOD chip enhances the culture of mouse embryos in a dynamic environment. To test the reproductive outcome of the embryos collected from an EWOD chip as a culture system, we transferred embryos to pseudo-pregnant female mice and produced live births. These results demonstrate that an EWOD-based microfluidic device is capable of culturing mammalian embryos in a microfluidic biological manner, presaging future clinical application.
Droplet microfluidic transporting module
(2009-10-08)
Hsu, Wen-Syang
;
Young, Han-Ping
;
Fan, Shih-Kang
A droplet microfluidic transporting module adapted for transporting a droplet is disclosed to include one or a number of connectors and one or a number of microfluidic transporting platform. Each connector defines a passage extending in one or multiple predetermined directions, and a first driving electrode extending along one side of the passage for the contact of the droplet to be transported. The microfluidic transporting platform is detachably electrically connected with the connector, defining a channel in communication with the passage of the connector and having a second driving electrode extending along one side of the channel for the contact of the droplet to be transported.
Fabrication of 3D Microfluidic Chip integrating Concentration gradient design and Perfusion system for Embryo coculture with Stromal cells
(2012-01-01)
Chang, Pei-Yu
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Chang, Kuo-Wei
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Lin, Ciou-Wen
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Shih, Po-Chen
;
Liu, Cheng-Hsien
Fabrication of 3D chip that enables cell culture under continuous flow perfusion and repeated in situ observation by light microscopy is described. Thin polydimethylsiloxane PDMS) membrane was etched to create an array of through-holes, and sandwiched between two PDMS channels to form an upper chamber and lower chamber. Thus we fabricated a 3D microfluidic chip which integrates the concentration gradient design and perfusion system for proposed embryo coculture with stromal cells.
Optimization of an optical disk manufacturing process for polymer microfluidic substrates by using the design of experiment methodology
(2010-07-01)
Wu, Chun-Han
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Hsu, Wen-Syang
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Fan, Kuo-Wei
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Lin, Yu-Ling
;
Lin, Yu-Cheng
We present an improved method for manufacturing microfluidic structures on a polymer-based substrate, and the design of experiment (DOE) is used to extract the optimum injection parameters. The long cycle time of the injection molding causes high costs in manufacturing, and this prevents conventional techniques from being widely used for mass production. Therefore, this study adopts a new optical disk process to reduce the cycle time. The cycle time of the new method can be reduced by more than ten-fold compared with that of traditional ones. Also, this new method can prevent damage on the mirror plate of the mold. The mold system is composed of a mold insert (stamper) holder and a vacuum system to join the mold insert with the mold. In this way, the time needed to change the stamper is drastically decreased. Our proposed method has the ability to reduce the time required to insert the mold from several hours to a few minutes, to prevent damage on the mirror plate of the mold, and to decrease the cycle time of molding from several minutes to 4 sec. The DOE is applied to study the effects of molding parameters on replication rate of depth, width deviation, birefringence, tilt and surface roughness of the microfluidic substrates. The experimental results show that the proposed method is suitable for mass production. (c) 2010 Society of Photo-Optical Instrumentation Engineers. [DOI: 10.1117/1.3491363]
Performance Enhancement of the In-Line Fan Equipped with the Guiding Vane and the Tail Body
(2014)
Yen, Hung-Cheng
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Hsu, Wen-Syang
;
Lin, Sheam-Chyun
;
機械工程學系
;
Department of Mechanical Engineering
This integrated numerical and experimental study intends to enhance the performance of an in-line fan with the implement of the guiding vane and the tail body. At first the flow flied associated with the original in-line fan is simulated and analyzed within the framework of CFD code Fluent, in which the finite volume method is applied. Next, the guiding vane is constructed based on the calculated flow characteristics, and attached in the downstream of rotor to smoothen the flow pattern. An appropriate guiding vane with high-performance and low-noise features can be achieved after several design iterations. In addition, the tail body connected to the motor is introduced for further enhancing the fan performance by reducing the sizes of wake and reversed flow behind the hub. Thereafter, to manufacture the mockup for experimental verification, the modified fan with guiding vane is plotted in the CAD/CAM format for mockup fabrication via the rapid-prototype technique. Moreover, a set of relations correlating the performance and noise of this fan prototype are executed inside AMCA test chamber and semianechoic chamber, respectively. Consequently, the feasibility of design scheme and numerical system can be verified according to these experimental results. In summary, this work provides a systematic scheme for designing and analyzing the in-line fan.
Realizing temperature-controlled digital microfluidic chips with versatile microelectrodes
(2007)
Wei, Jen-Hung
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Hsu, Wen-Syang
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Fan, Shih-Kang
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機械工程學系
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Department of Mechanical Engineering
Droplet heating and pumping were performed on a versatile microelectrode by selectively applying appropriate electric signals. The designed electrode is in a meander-tine shape and covered by an insulator. On the one hand, when a potential difference is applied along the electrode, power dissipated by the resistance of the electrode causes droplet heating. On the other hand, when an electric field exists across the insulator above the electrode, the charges stored in the capacitor alter the surface wettability and pump droplet. Manipulated droplets were placed between parallel plates with passivated versatile microelectrodes on the bottom plate and a Teflon-coated blank ITO on the top plate. We successfully applied a DC voltage at the two terminals of the meander-tine electrode to heat up the electrode as well as the droplet above. Besides, pumping droplets by EWOD was demonstrated by applying a proper AC voltage between the electrode on the bottom plate and the ITO on the top plate. With the proposed versatile microelectrode design and actuation scheme, heating and EWOD were obtained on an identical electrode. A digital microfluidic chip capable of droplet manipulation by EWOD and droplet heating was presented.
The Investigation of Nano-Roughening Effect on the Reliability Enhancement of Adhesive Bond for NEMS Manufacture Application
(2010-05-01)
Yang, Chia-Yeh
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Cheng, Yu-Ting
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Hsu, Wen-Syang
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機械工程學系
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電子工程學系及電子研究所
The paper shows the importance of nano-roughening on the bonding interface to the reliability enhancement of adhesive bond for ensuring the continuation of packaging shrinkage from MEMS to NEMS. The roughening is realized via a nonuniformly etching characteristic of PR which is etched and then utilized as an etching mask for following silicon etching process. Ultraviolet adhesive for silicon-to-glass bonding is utilized for the verification of the nano-roughening effect on NEMS hermetic encapsulation. The average roughnesses of the silicon substrate before and after roughening are 0.4 nm and 12.4 nm, respectively. Experimental results show that the roughness increase of silicon substrate can effectively provide more than 30% bonding strength enhancement and 30% leakage reduction. In addition, stamp-and-stick test shows that nano-roughening indeed provides a better adhesive characteristic that can further ensure the success of the stamp-and-stick process for nano/microfabrication.