检索结果-南通市图书馆

Transonic Moist Air Flow around a Circular Arc Blade with Bump

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2009年第4期18卷 325-331页

作者： A.B.M.Toufique HASAN shigeru MATSUO Toshiaki SETOGUCHI Heuy Dong KIM Department of Mechanical Engineering Bangladesh University of Engineering and Technology Department of Mechanical Engineering Saga University School of Mechanical Engineering Andong National University

The unsteady phenomena in the transonic flow around airfoils are observed in the flow field of fan, compressor blades and butterfly valves, and this causes often serious problems such as aeroacoustic noise and the vibration. In recent years, the effect of bump wall on the flow field around an airfoil has been investigated experimentally and as a result, it was observed that the bump wall is effective for the control of shock wave on the airfoil. In the transonic or supersonic flow field, a rapid expansion of moist air or steam gives rise to non-equilibrium condensation. In the present study, the effect of non-equilibrium condensation of moist air on the self-excited shock wave oscillation around a circular arc blade with or without a bump on the blade was investigated numerically. The results showed that the non-equilibrium condensation significantly reduced the flow field unsteadiness such as root mean of pressure oscillation and frequency compared to the case without the non-equilibrium condensation.

关键词： transonic flow moist air shock wave oscillation non-equilibrium condensation

Experimental Study of the Viscous Pump with a Helical Channel Rotor:Torsion Effect of the Channel

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2010年第2期19卷 154-159页

作者： Yasutaka HAYAMIZU Kyoji YAMAMOTO Shinichiro YANASE Toru HYAKUTAKE Shinichi MORITA shigeru OHTSUKA Department of Mechanical Engineering Yonago National College of Technology4448 Hikona-choYonago-shiTottori 683-8502 Graduate School of Natural Science and Technology Okayama University3-1-1 TushimanakaOkayama-shiOkayama 700-8530

The viscous pump,which has a rotor with a helical square channel,is studied *** non-dimen-sional channel curvature is taken to be about *** types of torsion of the channel are made to investigate the torsion effect on the flow *** measure the flux through the channel at a constant rotor speed by changing the pressures at the entrance and exit of the *** also observe the secondary flow at a cross-section of the *** of the results obtained are shown as follows:The friction factor along the channel to get the same flux is large for large channel torsion at a constant rotation,and becomes small when the favorable rotation of the rotor to the flow is *** for the secondary flow in a cross-section,there appear several types of *** there is no rotation,the secondary flow is almost a symmetric two-vortex type for small flux as is the ordinary Dean vortex,but it changes to a four-vortex type when the flux is *** secondary flow becomes asymmetric as the rotation is *** have unsteady flow patterns at large flux and rotation.

关键词： Viscous Pump Helical Channel Torsion Effect Secondary Flow Flow Visualization Dean Number Taylor Number

Jet Screech Reduction with Perforated Flat Reflector

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2008年第3期17卷 224-227页

作者： Md.Tawhidul Islam Khan Kenbu Teramoto shigeru Matsuo Toshiaki Setoguchi Department of Mechanical Engineering Saga University

In the present experimental study, investigations have been carded out to evaluate the performance of the new control technique of jet screech with different perforated flat reflectors. Mainly two types of porous flat reflectors had been used in the experiment. One reflector （reflector-V） designed for placing the reflector surface vertical to the jet axis, when, another type of reflector （reflector-H） designed for placing the reflecting surface horizontal to the jet axis. In both cases the reflectors had been placed at the nozzle （base tube with uniform cross-sectional area） exit. The diameter of the reflector-V was 15D when the diameter of the reflector-H was 10D. The porous area of the reflector-V was 6D and 4.5D for reflector-H where D indicated the diameter of the nozzle exit. The placement of the reflector at the exit of the nozzle reduces the sound pressure at the nozzle exit. Thus the muted sound can not excite the unstable disturbance at the nozzle exit and the loop of the feedback mechanism disappeared, finally, the generation of jet screech be cancelled. The suction space located at the back side of the porous surface of the reflector-V improves the efficiency of the screech control technique. However, in the case of reflector-H, the receptivity process of feedback loop had been controlled by reducing the disturbances at the effective shock fronts as well as at the nozzle exit. The performance of the proposed method was verified with a flat reflector concept and good performance in jet screech suppression has been confirmed in the case of porous reflector.

关键词： Supersonic jet noise screech tone feedback loop noise reduction porous reflector

A Study of Under-expanded Moist Air Jet Impinging on a Flat Plate

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2005年第4期14卷 334-340页

作者： Yumiko OTOBE shigeru MATSUO Masanori TANAKA Hideo KASHIMURA Heuy-Dong KIM Toshiaki SETOGUCHI Department of Control and Information Systems Engineering Kitakyushu National College of Technology5-20-1ShiiKokuraminami-kuKitakyushu-shiFukuoka 802-0985Japan Department of Mechanical Engineering Saga University1Honjo-machiSaga-shiSaga 840-8502Japan School of Mechanical Engineering College of Natural ScienceAndong National University388Song Cheon DongAndongKyung PookKorea

When a gas expands through a convergent nozzle in which the ratio of the ambient to the stagnation pressures is higher than that of the critical one, the issuing jet from the nozzle is under-expanded. If a flat plate is placed normal to the jet at a certain distance from the nozzle, a detached shock wave is formed at a region between the nozzle exit and the plate. In general, supersonic moist air jet technologies with non-equilibrium condensation are very often applied to industrial manufacturing processes. In spite of the importance in major characteristics of the supersonic moist air jets impinging to a solid body, its qualitative characteristics are not known satisfactorily. In the present study, the effect of the non-equilibrium condensation on the under-expanded air jet impinging on a vertical flat plate is investigated numerically in the case with non-equilibrium condensation, frequency of oscillation for the flow field becomes larger than that without the non-equilibrium condensation, and amplitudes of static pressure become small compared with those of dry air. Furthermore, the numerical results are compared with experimental ones.

关键词： compressible flow non-equilibrium condensation impinging jet simulation.

Droplet digital PCR for quantification of ITGA6 in a stool mRNA assay for the detection of colorectal cancers

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2017年第16期23卷 2891-2898页

作者： Elizabeth Herring shigeru Kanaoka éric Tremblay Jean-Francois Beaulieu Laboratory of Intestinal Physiopathology Department of Anatomy and Cell BiologyFaculty of Medicine and Health SciencesUniversitéde SherbrookeSherbrookeQC J1H5N4Canada Department of Gastroenterology Hamamatsu Medical CenterNaka-kuHamamatsu 432-8580Japan

AIM To investigate the use of droplet digital polymerase chain reaction(dd PCR) for detecting host m RNA markers in stools as a non-invasive test for colorectal cancer *** dd PCR and quantitative PCR were compared side by side for their performance in the detection of ITGA6 and ITGA6 A transcripts in stool samples obtained from patients with various types of colorectal lesions(advanced adenomas and stage Ⅱ-Ⅳ colorectal cancers) and control(patients displaying no pathological findings) using duplex Taq Man reactions for both methods. ITGA6 and ITGA6 A were chosen for this proof-of-concept study based on their relative medium and low abundance in stool samples, respectively, as established in a previous *** We found that the dd PCR and q PCR methods per-formed equally well in this Taq Man duplex assay for the detection of ITGA6 and ITGA6 A transcripts in stools of patients with colorectal lesions. For ITGA6, receiver operating characteristic(ROC) curve analysis showed comparable areas under the curve of 0.91(P < 0.0001) and 0.89-0.90(P < 0.0001) for the prediction of advanced adenomas and colorectal cancers, respectively. ITGA6 A, which was detected at very low levels in control patients, was found to be significantly elevated(over 40 times) in stage Ⅱ and Ⅲ colorectal cancers(P < 0.0002). Comparison of the two sets of data revealed a strong correlation of the copy numbers obtained by dd PCR and q PCR for both ITGA6 and ITGA6 *** We found that ITGA6 and ITGA6 A detection in stools of patients with colorectal cancers with dd PCR is comparable to that of q PCR using Taq Man assays.

关键词： Colorectal cancer Advanced adenoma Non-invasive screening Biomarker mRNA

Effect of Nozzle Geometry on the Flow Characteristics of Spiral Flow Generated through an Annular Slit

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2007年第2期16卷 149-154页

作者： shigeru MATSUO Tae-Hun KIM Toshiaki SETOGUCHI Heuy Dong KIM Yeon-Won LEE Department of Mechanical Engineering Saga University1Honjo-machiSaga-shiSaga 840-8502Japan Graduate school of Science and Technology Saga University1Honjo-machiSaga shiSaga 840-8502Japan School of Mechanical Engineering Andong National University388Songchun-dongAndong 760749Korea School of Mechanical Engineering College of EngineeringPukyong National UniversitySan 100Young-Dang DongBusanKorea

In comparison with previous researches of swirling flow, spiral flow generated in the spiral nozzle has some different flow characteristics. It does not need a forced tangential momentum to generate its velocity and has some different merits from the swirling flow such as long potential core and low tangential velocity. In this study, the effect of nozzle geometry on the flow characteristics in spiral nozzle was investigated by experiment and computation. As a result, the flow characteristics obtained by experiment has a satisfactory agreement with computational results, quantitatively and qualitatively.

关键词： nozzle flow characteristics momentum numerical simulation

Investigation on Temperature Separation and Flow Behaviour in Vortex Chamber

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2015年第2期24卷 149-154页

作者： Yuhi Matsuno Yusuke Fukushima shigeru Matsuo Tokitada Hashimoto Toshiaki Setoguchi Heuy Dong Kim Graduate School of Science and Engineering Saga University Department of Advanced Technology Fusion Saga University Institute of Ocean Energy Saga University School of Mechanical Engineering Andong National University

In the previous researches, it is known that the swirl flow in circular pipe causes the temperature separation. Recently, it is shown that the temperature separation occurs in a vortex chamber when compressed air are pumped into this device from the periphery. Especially, in a cavity installed in the periphery of the chamber, the highest temperature was observed. Therefore, it is expected that this device can be used as a heat source in the engineering field. In recent researches, the mechanism of temperature separation in vortex chamber has been investigated by some researchers. However, there are few researches for the effect of diameter and volume of vortex chamber, height of central rod and position of cavity on the temperature separation. Further, no detailed physical explanation has been made for the temperature separation phenomena in the vortex chamber. In the present study, the effects of chamber configuration and position of the cavity on temperature separation in the vortex chamber were investigated experimentally.

关键词： Compressible flow Vortex chamber Cavity flow Temperature separation

Effect of Axisymmetric Sonic Nozzle Geometry on Characteristics of Supersonic Air Jet

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2004年第2期13卷 121-126页

作者： shigeru MATSUO Masanori TANAKA Yumiko OTOBE Hideo KASHIMURA Heuy-Dong KIM Toshiaki SETOGUCHI Department of Mechanical Engineering Saga University 1 Honjo-machi Saga-shi Saga 840-8502 Japan Department of Control and Information Systems Engineering Kitakyushu National College of Technology 5-20-1 Shii Kokuraminami-ku Kitakyushu-shi Fukuoka 802-0985 Japan School of Mechanical Engineering College of Natural Science Andong National University 388 Song-Cheon Dong Andong Kyung-Pook Korea

The effect of nozzle geometry on sonic line and characteristics of supersonic air jet was studied. Computational fluid dynamics was applied in this study. The axisymmetric nozzle geometries investigated were two different contour converging nozzles, two different conically converging sharp-edged nozzles and a sharp-edged orifice. The results show that the supersonic jet structure, sonic line and streamlines in supersonic jet are strongly influenced by the nozzle geometry, and the total pressure loss increases with the increase of Mach disk diameter. The present numerical simulation is an effective tool to evaluate compressible flows in supersonic air jet.

关键词： compressible flow supersonic jet non-equilibrium condensation simulation.

Control of the Asymmetric Flow in Rocket Nozzles

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2013年第2期22卷 97-102页

作者： shigeru Matsuo Shotaro Suetsugu Junji Nagao Tokitada Hashimoto Toshiaki Setoguchi Heuy Dong Kim Department of Advanced Technology Fusion Saga University Graduate School of Science & Engineering Saga University Institute of Ocean Energy Saga University School of Mechanical Engineering Andong National University

In some rocket nozzle flows, the existence of the transition from FSS to RSS and the occurrence of asymmetric flow are known in previous researches. As a result, the transition causes excessive side-loads that may damage the nozzle. Thus, it is important to investigate the method in order to control the asymmetric flow separation. In the present study, the relationship between the asymmetric separation and the rate of change of the pressure ratio with time was investigated from the point of view of the transition from FSS to RSS in the supersonic nozzle experimentally. Further, change of the flow separation by using step and cavity, and the possibility of the control was demonstrated. As a result, it was shown that the method using a cavity was effective for the control of the separation pattern.

关键词： Compressible flow Asymmetric shock wave Rocket nozzle Control Experiment