Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Transactions of the Korean Society of Mechanical Engineers B
Journal Basic Information
Journal DOI :
The Korean Society of Mechanical Engineers
Editor in Chief :
Volume & Issues
Volume 24, Issue 12 - Dec 2000
Volume 24, Issue 11 - Nov 2000
Volume 24, Issue 10 - Oct 2000
Volume 24, Issue 9 - Sep 2000
Volume 24, Issue 8 - Aug 2000
Volume 24, Issue 7 - Jul 2000
Volume 24, Issue 6 - Jun 2000
Volume 24, Issue 5 - May 2000
Volume 24, Issue 4 - Apr 2000
Volume 24, Issue 3 - Mar 2000
Volume 24, Issue 2 - Feb 2000
Volume 24, Issue 1 - Jan 2000
Selecting the target year
Numerical Analysis of Drag-Reducing Turbulent Flow by Polymer Injection with Reynolds Stress Model
Ko, Kang-Hoon ; Kim, Kwang-Yong ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 1~8
DOI : 10.22634/KSME-B.2000.24.1.1
A modified low-Reynolds-number Reynolds stress model is developed for the calculation of drag-reducing turbulent flows induced by polymer injection. The results without polymer injection are compared with the results of direct numerical simulation to ensure the validity of the basic model. In case of drag reduction, profiles of mean velocity and Reynolds stress components, in two-dimensional channel flow, obtained with a proper value of viscosity ratio are presented and discussed. Computed mean velocity profile is in very good agreement with experimental data. And, the qualitative behavior of Reynolds stress components with the viscosity ratio is also reasonable.
Analysis of Radiative Heat Transfer and Mass Transfer During Multi-Wafer Low Pressure Chemical Vapor Deposition Process
Park, Kyoung-Soon ; Choi, Man-Soo ; Cho, Hyoung-Joo ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 9~20
DOI : 10.22634/KSME-B.2000.24.1.9
An analysis of heat and mass transfer has been carried out for multi-wafer Low Pressure Chemical Vapor Deposition (LPCVD). Surface radiation analysis considering specular radiation among wafers, heaters, quartz tube and side plates of the reactor has been done to determine temperature distributions of 150 wafers in two dimensions. Velocity, temperature and concentration fields of chemical gases flowing in a reactor with multi-wafers have been then determined, which determines Si deposition growth rate and uniformity on wafers using two different surface reaction models. The calculation results of temperatures and Si deposition have been compared and found to be in a reasonable agreement with the previous experiments.
Development of Single-Frame PIV Velocity Field Measurement Technique Using a High Resolution CCD Camera
Lee, Sang-Joon ; Shin, Dae-Sig ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 21~28
DOI : 10.22634/KSME-B.2000.24.1.21
Although commercial PIV systems have been widely used for the non-intrusive velocity field measurement of fluid flows, they are still under development and have considerable room for improvement. In this study, a single-frame double-exposure PIV system using a high-resolution CCD camera was developed. A pulsed Nd:Yag laser and high-resolution CCD camera were synchronized by a home-made control circuit. In order to resolve the directional ambiguity problem encountered in the single-frame PIV technique, the second particle image was genuinely shifted in the CCD sensor array during the time interval dt. The velocity vector field was determined by calculating the displacement vector at each interrogation window using cross-correlation with 50% overlapping. In order to check the effect of spatial resolution of CCD camera on the accuracy of PIV velocity field measurement, the developed PIV system with three different resolution modes of the CCD camera (512
2K) was applied to a turbulent flow which simulate the Zn plating process of a steel strip. The experimental model consists of a snout and a moving belt. Aluminum flakes about
diameter were used as scattering particles for the liquid flow in the zinc pot and the gas flow above the zinc surface was seeded with atomized olive oil with an average diameter of 1-
. Velocity field measurements were carried out at the strip speed
=1.0 m/s. The 2K
2K high-resolution PIV technique was significantly superior compared to the smaller pixel resolution PIV system. For the cases of 512
512 and 1K
1K pixel resolution PIV system, it was difficult to get accurate flow structure of viscous flow near the wall and small vortex structure in the region of large velocity gradient.
The Effect of Ambient Air Condition on a Hot Steel Plate Cooled by Impinging Water Jet
Lee, Pil-Jong ; Choi, Hae-Won ; Lee, Seung-Hong ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 29~38
DOI : 10.22634/KSME-B.2000.24.1.29
It is observed that the cooling capacity of impinging water jet is affected by the seasonal conditions in steel manufacturing process with large scale. To confirm this phenomena, the cooling experiments of a hot steel plate by a laminar jet were conducted for two different initial ambient air temperature(
) in a closed chamber, and an inverse heat conduction method is applied for the quantitative comparison. It is found that the cooling capacity under
air temperature is lower than that under
, as is the saturated water vapor is more easily observed, and the amount of total extracted heat in the case of
is smaller by nearly 15% than that of
case. From these results, it is thought that the quantity of water vapor, which could be absorbed until saturation, effects on the mechanism of boiling heat transfer.
Modelling and Simulation of Rotary Compressor in Refrigerator
Park, Min-Woo ; Chung, Youn-Goo ; Park, Kyoung-Woo ; Pak, Hi-Yong ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 39~49
DOI : 10.22634/KSME-B.2000.24.1.39
This paper presents the modeling approach that can predict transient behavior of rotary compressor. Mass and energy conservation laws are applied to the control volume, real gas state equation is used to obtain thermodynamic properties of refrigerant. The valve equation is solved to analyze discharge process also. Dynamic analysis of vane and roller is carried out to gain friction work. From the above modeling, the performance of rotary compressor with radial clearance and friction loss is investigated numerically. The performance of each refrigerant is estimated, respectively by applying R12, R134a, and R290/ R600a mixture.
An Experimental Study on Heat Storage and Heat Recovery Characteristics of a Latent Heat Storage Tank with Horizontal Shell and Tube Type
Kwon, Young-Man ; Seo, Hye-Sung ; Moh, Jung-Ha ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 50~59
DOI : 10.22634/KSME-B.2000.24.1.50
An experimental study has been carried out in order to investigate the heat storage characteristics for a latent heat storage tank with horizontal shell and tube type. The heat exchanger consisted of horizontal cylindrical capsules with a staggered tube bank layout. Based on the obtained data, the effects of flow rate and inlet fluid temperature on the melting time and heat storage rates were examined. It is found that the melting time decreased with increase of the flow rate and the inlet temperature. Results also show that at the initial stage of heat transfer the heat storage rate represents the maximum value and rapidly decreases.
An Experimental Study on Unsteady Heat Transfer of Spray-Impinging Plate in a Pressurized Chamber
Cho, Chang-Kwun ; Lee, Yeol ; Koo, Ja-Ye ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 60~67
DOI : 10.22634/KSME-B.2000.24.1.60
An experimental investigation on transient heat transfer phenomena of impinging diesel-spray on a flat plate in a pressurized chamber is carried out. A diesel spray is injected from a single-hole nozzle and impinges to a heated flat plate in the chamber. A fast-response thermocouple installed in the top surface of the plate measures the transient variation of surface temperature of the plate under various conditions of the chamber pressures. Utilizing the semi-infinite model, the temporal variation of the heat flux on the plate is determined. Effects of various parameters, such as vertical distances between the nozzle and the plate, radial distances from the injection-axis, and the chamber pressures, on the heat flux characteristics of impinging diesel-spray are studied.
An Experimental Study on Flame Spread in One-Dimensional Droplet Array with Forced Convection
Park, Jeong ; Lee, Kiman ; Niioka, Takashi ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 68~74
DOI : 10.22634/KSME-B.2000.24.1.68
Experimental investigation on flame spread along suspended droplet arrays have been conducted with various droplet spacings and ambient air velocities. Especially, an opposed air stream is introduced to simulate fundamental flame spread behaviors in spray combustion. High-speed chemiluminescence imaging technique of OH radicals has been adopted to measure flame spread rates and to observe various flame spread behaviors. The fuel used is n-Decane and the air velocity varies from 0 to 17cm/s. The pattern of flame spread is grouped into two: a continuous mode and an intermittent one. It is found that there exists droplet spcings, above which flame spread does not occur. The increase of ambient air velocity causes the limit droplet spacing of flame spread to become small due to the increase of apparent flame stretch. As the ambient air velocity decreases, flame spread rate increases and then decreases after taking a maximum flame spread rate. This suggests that there exists a moderate air flowing to give a maximum flame spread rate due to enhanced chemical reaction by the increase of oxidizer concentration.
Performance and Flow Characteristics of a Forward Swept Propeller Fan
Kim, Jin-Kwon ; Kang, Shin-Hyoung ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 75~84
DOI : 10.22634/KSME-B.2000.24.1.75
Performance and flow characteristics of a small forward swept propeller fan for home refrigerators are studied experimentally. An unusual discontinuity is observed in the performance curve of the fan. Mean flow fields measured with as-hole Pitot probe reveal that the flow is axial at the high flow rate and radial at the low flow rate. The flow structure changes abruptly across the discontinuity. Unsteady flow measurements with a set of hot-wire probes indicate that near the discontinuity a single-cell stall rotates at 40% speed of the fan speed, while away from the discontinuity the flow shows periodic variation corresponding to the blade passage frequency. Phase-lock averaged flow fields measured with a triple-sensor hot-wire probe show that there appears radially inward flow over the pressure side of the blade and the outward passage flow over the tip.
Development of Easy Measurement Method of Orthogonal Triple-Sensor Hot-Wire Anemometer
Kim, Jin-Kwon ; Kang, Shin-Hyoung ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 85~92
DOI : 10.22634/KSME-B.2000.24.1.85
Easy measurement method of orthogonal triple-sensor hot-wire anemometer is developed. Advantages of the new method is that it does not require either the exact orthogonality of the installed wires which cannot be kept during the probe manufacture and repair, nor the knowledge of the wire installation angles and the yaw and pitch coefficient of the wires. The new method introduced yaw and pitch calibration coefficients which are designed to increase monotonically with yaw and pitch angles. So the resulting calibration network is simple to recognize compared with that of the previously suggested calibration method. Verification experiments showed good accuracy and independency of the directional calibration on velocity.
The Spray Characterization Using Planar Imaging Technique
Lee, Kyung-Jin ; Jung, Ki-Hoon ; Yoon, Young-Bin ; Jeong, Kyung-Seok ; Jeung, In-Seuck ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 93~101
DOI : 10.22634/KSME-B.2000.24.1.93
The characteristics of spray nozzle have been quantified with the measurement of fluorescence and Mie scattering images. To correct the attenuation of the incident light sheet, a sequential double-pass light sheet system and the geometrical averaging of two images was implemented. Quantitative mass flux distribution of spray was obtained from fluorescence image. 3-D image is reconstructed using 2-D radial images. Sauter mean diameter (SMD) distribution was determined using the ratio of fluorescence signal intensity and Mie scattering signal intensity and the values were quantified with PDP A data. The measurement of mass flux and SMD using planar imaging technique agee with PDP A data fairly well in the low density region. However, in dense region， there are significant errors caused by secondary scattering. It was found that the planar imaging technique provides many advantages over the point measurement technique, such as PDP A, and can be implemented for quantitative measurement, especially in low density region.
A Study on the Filling and Solidification Process During Gravity Casting Using Implicit VOF Method
Im, Ik-Tae ; Kim, Woo-Seung ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 102~113
DOI : 10.22634/KSME-B.2000.24.1.102
In this study, a three-dimensional gravity casting problem has been examined to investigate a coupled phenomenon of the filling and solidification process. This work simultaneously considers the two key phenomena of metal casting : the fluid flow during mold filling, and solidification process. The VOF method is used to analyze the free surface flow during filling and the equivalent specific heat method is employed to model the latent heat release during solidification. The time-implicit filling algorithm is applied to save the computational time for analyzing the mold filling process. The three-dimensional benchmark problem used in the MCWASP VII has been solved using both the implicit and explicit algorithm, and the present results are compared with the benchmark experimental results and the other numerical results.
Velocity Field Measurement of Flow Around an Axial Fan Using a Phase Averaged 2-Frame PTV Technique
Choi, Jay-Ho ; Kim, Hyoung-Bum ; Lee, Sang-Joon ; Lee, In-Seop ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 114~123
DOI : 10.22634/KSME-B.2000.24.1.114
The flow structure around a rotating axial-fan was experimentally investigated using a phase averaging velocity field measurement technique. The fan blades were divided into 4 different phases, for which 500 velocity fields were acquired for each phase angle with a 2-frame PTV system. Velocity field measurements were also carried out at two planes parallel to the axis of rotation, with offsets toward the radial direction of the fan. For accurate synchronization of the PTV system with the phase of the axial fan, two synchronization circuits were employed with a photo-detector attached to the rotating shaft. The phase averaged velocity fields show periodic variations with respect to the blade phase. The periodic formation of vortices at the blade tip is also observed in vorticity contour plots. Locations of local maximum turbulence intensities in the axial and radial directions are found to be located in an alternating pattern. These experimental results can be used to validate numerical calculations and to understand the flow characteristics of an axial fan.
Pool Boiling Performance of Enhanced Tubes for a Flooded Evaporator
Kim, Nae-Hyun ; Kim, Tae-Hyung ; Park, Woon-Jin ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 124~131
DOI : 10.22634/KSME-B.2000.24.1.124
In this study, pool boiling performance of Turbo/B-type metal-formed tubes was investigated. Tubes with three different cavity gap width(0.04 mm, 0.07 mm, 0.1 mm) were manufactured and tested using R-11, R-123 and R-134a. Tests were conducted at two different saturation temperatures
Heat flux was varied from 10 kW/m2 to 50 kW/m2. It was found that optimum gap width varied for different refrigerants. For low-pressure refrigerants such as R-11 or R-123, optimum gap width was 0.07 mm. For high-pressure refrigerant R-134a, however, the optimum value was 0.1 mm. Compared with the heat transfer performance of the smooth tube, the metal-formed tubes enhanced the heat transfer coefficients significantly - 6.5 times for R-11, 6.0 times for R-123 and 5.0 times for R-134a (at
saturation temperature and 40 kW/m2 heat flux), which are comparable with the performance of foreign products. The heat transfer coefficients of R-134a were larger than those of R-11 or R-123, and they increased as the saturation temperature increased.
A Study on the Aerodynamic Noise of a Supersonic Exhaust Nozzle of Slotted Tube
Lee, Dong-Hoon ; Seto, Kunisato ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 132~142
DOI : 10.22634/KSME-B.2000.24.1.132
The objective of this study is to experimentally investigate the noise propagating characteristics, the noise reduction mechanism and the performance of a slotted tube attached at the exit plane of a circular convergent nozzle. The experiment is performed through the systematic change of the jet pressure ratio and the slot length under the condition of two kinds of open area ratios, 25% and 51%. The open area ratio calculated by the tube length equivalent for the slot length is defined as the ratio of the total slot area to the surface area of a slotted tube. The experimental results for the near and far field sound, the visualization of jet structures and the static pressure distributions in the jet passing through a slotted tube are presented and explained in comparison with those for a simple tube. The propagating characteristics of supersonic jet noises from the slotted tube is closely connected with the slot length rather than the open area ratio, and its propagating pattern is similar to the simple tube. It is shown that the slotted tube has a good performance to suppress the shock-associated noise as well as the turbulent mixing noise in the range of a limited jet pressure and slot dimension. The considerable suppression of the shock‘associated noise is mainly due to the pressure relief caused by the high-speed jets passing through the slots on the tube. Both the strength of shock waves and the interval between them in a jet plume are decreased by the pressure relief. Moreover, the pressure relief is divided into the gradual and the sudden relief depending upon the open area ratio of the slotted tube. Consequently, the shock waves in a jet plume are also changed by the type of pressure relief. The gradual pressure relief caused by the slotted tube with the open area ratio 25% generates the weak oblique shock waves. On the contrary, the weak normal shock waves appear due to the sudden pressure relief caused by the slotted tube with the open area ratio 51%.
The Effect of Tube Orientation on Pool Boiling Heat Transfer
Kang, Myeong-Gie ;
Transactions of the Korean Society of Mechanical Engineers B, volume 24, issue 1, 2000, Pages 143~151
DOI : 10.22634/KSME-B.2000.24.1.143
In order to clarify the effect of tube orientation on pool boiling heat transfer, the experiments were carried out for the saturated pool boiling of water at atmospheric pressure. Through the tests a series of data sets for heat flux versus wall superheat has been obtained using various combinations of tube diameters (D=9.7
25.4mm)， surface roughness (
60.9nm)， and tube orientations (horizontal and vertical). ηei experimental results show that the slope of heat flux versus wall superheat becomes smaller than that of the horizontal tube as the surface roughness decreases from
=15.1nm. Such that， two curves for the horizontal and vertical tubes cross each other in accordance with surface roughness and the crossing point can be suggested as q" = ‘-4.768+1.334