Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods最新文献

{"title":"Multi-Mode Methanol Flow Boiling Under Atmospheric and Subatmospheric Pressures","authors":"W. W. Lin, Y. Liao, D. J. Lee","doi":"10.1115/imece1996-0113","DOIUrl":"https://doi.org/10.1115/imece1996-0113","url":null,"abstract":"\u0000 This is a continuation work of Lin and Lee (1996 National Heat Transfer Conference, Houston) while reporting the experimental results of multi-mode methanol How boiling under atmospheric and subatmospheric pressures. An axial (discrete) heat flux distribution with neutral stability at which nucleate and film boiling can coexist steadily is identified under various system pressures and crossflow rates. Below this heat flux distribution, nucleate boiling mode is more stable. Above this distribution, film boiling becomes the more stable mode. An equal-area criterion based on the difference between bottom heat flux and surface boiling heat flux, and the wall superheat temperature relationship is employed for interpreting the experimental data. Effects of system pressure, mass flowrate, liquid subcooling and bottom heat flux on the relative stability of nucleate and film boiling modes are discussed.","PeriodicalId":324954,"journal":{"name":"Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130515884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Isokinetic Sampling Technique in Stratified Multiphase Flows","authors":"S. H. Khor, M. Mendes-Tatsis, G. Hewitt","doi":"10.1115/imece1996-0099","DOIUrl":"https://doi.org/10.1115/imece1996-0099","url":null,"abstract":"\u0000 This paper describes the development of an isokinetic sampling probe ultimately intended for application in three-phase gas-liquid-liquid stratified flows in horizontal pipes. The probe is designed with an aim to give information on local fluid flow rates and the fractions of the respective liquids (oil and water) within the flow. The paper also presents the validation of the developed isokinetic sampling probe against single phase flow measurements and preliminary tests with the probe in air-water and air-oil-water stratified flows in a horizontal pipe. The results obtained (believed to be the first application of such a probe in stratified flows) are encouraging and consistent with previous findings.","PeriodicalId":324954,"journal":{"name":"Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127474115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flow Boiling Inside Enhanced Heat Transfer Tubes","authors":"G. Xiang, H. Y. Hu, X. Peng, B. Wang","doi":"10.1115/imece1996-0104","DOIUrl":"https://doi.org/10.1115/imece1996-0104","url":null,"abstract":"\u0000 A tube with longitudinal microchannels on inside wall was developed to enhance flow boiling heat transfer. The experimental investigation was conducted to identify the flow boiling heat transfer performance of liquid through the enhanced tubes. The flow boiling heat transfer in the enhanced tubes is greatly intensified, especially for the fully-developed nucleate boiling regime. The heat transfer coefficient in microchanneled tubes with smaller diameter is increased with a magnitude of 170% compared with the identical smooth tubes. The geometric configuration of microchannels and tubes would have significant effect of the flow boiling inside microchanneled tubes. The heat transfer performance of the microchanneled tubes is as good as or even better than that of other existing enhanced tubes.","PeriodicalId":324954,"journal":{"name":"Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122321765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flow Patterns and Their Transitions of Vertically Downward Two-Phase Flow With High Viscosity Liquid","authors":"Shu-Zhong Wang, Zonghu Lin, Zhiran Liang","doi":"10.1115/imece1996-0115","DOIUrl":"https://doi.org/10.1115/imece1996-0115","url":null,"abstract":"\u0000 The flow patterns and their transitions of air-oil two-phase flows in a vertically downward pipe were investigated experimentally and theoretically. The pipe diameter was 29mm, and the oil and air superficial velocity were up to 4m/s and 20m/s respectively. The flow pattern identifications were carried out by means of the combination of visual observations and analysis for corresponding pressure drop pulsation signals. The investigations express that the flow patterns and their transitions of oil and gas two-phase flow somewhat differed from those of low viscous liquid and gas two-phase flows. On the basis of this study and other previous investigations, one available approach is presented to predict the flow patterns and their transitions in vertically downward two-phase flow with high-viscosity liquid.","PeriodicalId":324954,"journal":{"name":"Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128116120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phase Distribution Measurements in Liquid-Liquid Pipeline Flows Using an Impedance Probe","authors":"P. Angeli, G. Hewitt","doi":"10.1115/imece1996-0105","DOIUrl":"https://doi.org/10.1115/imece1996-0105","url":null,"abstract":"\u0000 A high frequency impedance probe was used for volume fraction distribution measurements and flow pattern identification in oil-water flow. The signal processing technique was based on a method by van der Welle (1985) that attributes to the beginning of the signal rise or fall the contact of the interface with the probe tip. The experiments were performed in two 1 inch nominal bore horizontal test sections made from stainless steel and acrylic resin. Measurements were made for mixture velocities from 1.3 m/s to 1.7 m/s and input oil volume fractions from 25% to 85%. Under these conditions different complex flow patterns exist, whose discrimination with visual observation is difficult. The results revealed that the mixing of the liquid phases is much greater in the rougher steel pipe than in the acrylic pipe under the same conditions and also helped to clearly identify the three layer, the stratified mixed and the fully mixed flow patterns.","PeriodicalId":324954,"journal":{"name":"Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134118433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Studies of Interfacial Area in a Horizontal Slug Flow","authors":"J. Riznic, S. Lewis, G. Kojasoy","doi":"10.1115/imece1996-0091","DOIUrl":"https://doi.org/10.1115/imece1996-0091","url":null,"abstract":"\u0000 The internal flow structure of horizontal slug flow has been experimentally investigated by measuring the local interfacial area concentration, void fraction and interfacial velocity distribution. The four-sensor electroresistivity probe was used to detect the instantaneous interface velocities and interfacial area. Experimental studies were performed on the plug/slug flow regimes with an air-water system. Data were acquired at the axial location of L/D = 253 from the mixing chamber. Four different liquid flow rates in combination with five different gas injection rates were studied. The superficial liquid velocity was varied between 0.55 and 2.20 m/s and gas velocity between 0.27 and 2.20 m/s. With these experimental conditions, the total void fraction, including contributions from small and large slug bubbles, ranged from 10 to 70%. The void fraction measurements were checked against the raw signal data, high speed video recordings, and measurements obtained by the hot film anemometer probe. The agreement between the data was very good, confirming that the four-sensor probe measurements can be performed with a high degree of confidence. In the region of transition between plug and slug flow regime, with an increase in the gas flow rate, the number and contribution of the small follow-up bubbles increased. The increase in the liquid flow rate produced similar effects. The slug bubble frequency also increased with an increase in the gas velocity and also slugs are longer at higher gas flow rates.\u0000 Total interfacial area concentration profile includes the contribution from both slugs and small follow-up bubbles. Experimental data showed higher interfacial area concentration in the lower part of a slug bubble, with a larger curvature of interface. This is expected, since along the steeper curvature a ratio of local surface area to volume is increasing. Radial profiles of interfacial area concentration for slug bubbles show almost a flat profile in the upper part of slug bubble. The larger values of the total interfacial area concentration indicates that the contribution from the small bubbles is increasing. Experiments showed that in the plug/slug flow regime, contribution from the increasing number of small bubbles to the interfacial area concentration is substantial in upper part of the horizontal channel.","PeriodicalId":324954,"journal":{"name":"Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126945448","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Void Fraction Fluctuations in Two-Phase Flow at 1-G and μ-G","authors":"K. J. Elkow, K. Rezkallah","doi":"10.1115/imece1996-0100","DOIUrl":"https://doi.org/10.1115/imece1996-0100","url":null,"abstract":"\u0000 Void fraction measurements for adiabatic, two-phase vertical upward, water-air flow in a 9.53 mm ID tube were obtained using a helical wound capacitance sensor. Comparisons were made between 1-g and μ-g void fraction values by matching the flow rates obtained at μ-g conditions. A Probability Density Function was used to analyze the void fraction signals. It was found that a wider fluctuation in void fraction values occurred for slug flow at 1-g as compared to μ-g. For higher flow rates such as with annular flow, inertia forces become dominant. For these flows it was found that the void fraction fluctuations were similar at 1-g and μ-g conditions.","PeriodicalId":324954,"journal":{"name":"Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130705310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scaling of High Heat Flux Flow Boiling Flow Systems","authors":"A. Castrogiovanni, P. Sforza","doi":"10.1115/imece1996-0092","DOIUrl":"https://doi.org/10.1115/imece1996-0092","url":null,"abstract":"\u0000 The scaling of high heat flux boiling flow systems is examined using a computational technique newly developed by the present authors. The current work is an extension of our previously reported two-dimensional scaling technique to include flow development along the axis of a cooling channel. The new approach involves the solution of the energy equation for a pipe flow subjected to a step change in wall heat flux assuming a fully developed turbulent velocity profile at the point of initial heating. A boiling-induced turbulent eddy diffusivity term is used with an adaptive genetic algorithm closure scheme to predict both the transition to, and development of, the partial nucleate boiling regime based on a postulated minimization of the local wall temperature. Examination of the constitutive equations in non-dimensional form in conjunction with the use of previously established fluid-property scaling tools, leads to the development of a scaling procedure. Reasonable similarity between a high heat flux boiling flow system utilizing water, and a lower heat flux boiling flow system using R-12 is demonstrated. A numerical experiment is carried out to illustrate the scaling technique.","PeriodicalId":324954,"journal":{"name":"Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117077215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat Transfer Analysis and Evaluation for Two-Phase Flow in Porous-Channel Heat Sinks","authors":"G. Peterson, C. Chang","doi":"10.1080/10407789708914028","DOIUrl":"https://doi.org/10.1080/10407789708914028","url":null,"abstract":"\u0000 Presented here are the results of a heat transfer analysis of two-phase heat dissipation utilizing high-conductivity porous channels as a heat sink. A consistent set of conservation equations based on phase-averaged properties of the fluid are derived from the conventional ones and solved numerically by the finite volume method. The results indicate that the high conductivity and large solid-fluid contact surface of the porous channel result in a high heat transfer coefficient. In addition, the surface temperature was shown to remain quite uniform. Overall, the results confirm the expectation that the use of two-phase heat dissipation in high conductivity porous channels may be an acceptable cooling technique for future electronic devices where much higher heat fluxes than the present levels need to be removed effectively.","PeriodicalId":324954,"journal":{"name":"Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124992189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temperature Measurements via Narrow Line Laser Absorption of Carbon Dioxide","authors":"M. Wooldridge","doi":"10.1115/imece1996-0136","DOIUrl":"https://doi.org/10.1115/imece1996-0136","url":null,"abstract":"Theoretical development for temperature measurements via narrow line, infrared absorption of carbon dioxide (CO2) is presented. The proposed technique is based on rapid-scanning of two adjacent absorption line shapes. Spectroscopic considerations for sensitivity to temperature measurements are discussed. Several line pairs are evaluated, and the R(58) and R(60) transitions of the (00°1) ← (00°0) band are suggested for use in high temperature measurements for combustion systems.","PeriodicalId":324954,"journal":{"name":"Heat Transfer: Volume 3 — Experimental Studies in Multiphase Flow; Multiphase Flow in Porous Media; Experimental Multiphase Flows and Numerical Simulation of Two-Phase Flows; Fundamental Aspects of Experimental Methods","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115741907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}