Home / Advanced Search

  • Title/Keywords

  • Author/Affliations

  • Journal

  • Article Type

  • Start Year

  • End Year

Update SearchingClear
  • Articles
  • Online
Search Results (35)
  • Open Access

    ARTICLE

    EXPERIMENTAL STUDY OF ENHANCED NUCLEATE BOILING HEAT TRANSFER ON UNIFORM AND MODULATED POROUS STRUCTURES

    Calvin Hong Lia, G. P. Petersonb,*

    Frontiers in Heat and Mass Transfer, Vol.1, No.2, pp. 1-10, 2010, DOI:10.5098/hmt.v1.2.3007

    Abstract An experimental investigation of the Critical Heat Flux (CHF) and heat transfer coefficient (HTC) of two-phase heat transfer of de-Ionized (DI) water, pool boiling was conducted using several kinds of sintered copper microparticle porous uniform and modulated structures. The modulated porous structure reached a heat flux of 450 W/cm2 and a heat transfer coefficient of 230,000 W/m2K. The thick and thin uniform porous structures achieved CHFs of 290 W/cm2 and 227 W/cm2 , respectively, and heat transfer coefficients of 118,000 W/m2K and 104,000 W/m2K. The mechanisms for the dramatically improved CHFs and HTCs were identified with assistance of a visualization… More >

  • Open Access

    ARTICLE

    PREDICTION OF BINARY MIXTURE BOILING HEAT TRANSFER IN SYSTEMS WITH STRONG MARANGONI EFFECTS

    Kenneth M. Armijo, Van P. Carey*

    Frontiers in Heat and Mass Transfer, Vol.1, No.2, pp. 1-6, 2010, DOI:10.5098/hmt.v1.2.3003

    Abstract This paper investigates the impact of Marangoni phenomena for low concentrations of 2-propanol/water and methanol/water mixtures. In real systems the addition of small levels of surface-active contaminants can affect the surface tension of the liquid-vapor interface and thermodynamic conditions in this region. Analysis was performed for three widely accepted binary mixture correlations to predict heat flux and superheat values for subatmospheric experimental data using bulk fluid and film thermodynamic properties. Due to the non-ideal nature of these alcohol/water mixtures, this study also employs an average pseudo single-component (PSC) coefficient in place of an ideal heat transfer coefficient (HTC) to improve… More >

  • Open Access

    ARTICLE

    VOLUME OF FLUID SIMULATION OF BOILING TWO-PHASE FLOW IN A VAPOR-VENTING MICROCHANNEL

    Chen Fang*, Milnes David, Anita Rogacs, Kenneth Goodson

    Frontiers in Heat and Mass Transfer, Vol.1, No.1, pp. 1-11, 2010, DOI:10.5098/hmt.v1.1.3002

    Abstract Vapor-venting microchannel heat exchangers are promising because they address the problems of high pressure drop, flow instability, and local dryout that are common in conventional two-phase microchannel heat sinks. We present a 3D numerical simulation of the vapor-venting process in a rectangular microchannel bounded on one side by a hydrophobic porous membrane for phase-separation. The simulation is based on the volume of fluid (VOF) method together with models for interphase mass transfer and capillary force. Simulation shows the vapor-venting mechanism can effectively mitigate the vapor accumulation issue, reduce the pressure drop, and suppress the local dry-out in the microchannel. Pressure… More >

  • Open Access

    ARTICLE

    SATURATED AND SUBCOOLED POOL BOILING OF HFE-7200 MIXTURES ON A COPPER NANOWIRE SURFACE

    Aravind Sathyanarayanaa, Pramod Warrierb, Yogendra Joshia,*, Amyn Tejab

    Frontiers in Heat and Mass Transfer, Vol.2, No.4, pp. 1-7, 2011, DOI:10.5098/hmt.v2.4.3007

    Abstract Electrical and chemical compatibility requirements of electronic components pose significant constraints on the choice of liquid coolants. Dielectric coolants such as Novec fluids and fluoroinerts are plagued by poor thermal properties. This necessitates the development of new heat transfer fluids. In this study we examine mixture formulations that provide an avenue for enhancing the properties of existing heat transfer fluids. Mixture formulations of Novec fluid (HFE 7200) with Methanol and Ethoxybutane are considered. Pool boiling experiments are performed on a copper nanowire surface. The results show an improvement of 24% and 11% in the CHF of HFE 7200 – Methanol… More >

  • Open Access

    ARTICLE

    POOL BOILING CHF FOR PENTANE, HEXANE, METHANOL, FC-72, FC-87, AND R113 ON A SMOOTH HORIZONTAL SURFACE

    Cheng-Kang Guan, James F. Klausner*, Renwei Mei

    Frontiers in Heat and Mass Transfer, Vol.2, No.4, pp. 1-6, 2011, DOI:10.5098/hmt.v2.4.3002

    Abstract Pool boiling critical heat flux (CHF) has been measured for pentane, hexane, methanol, FC-72, FC-87, and R113 on a 25.4 mm diameter smooth brass horizontal surface at five different reduced pressures ranging from 0.01to 0.24. The CHF data are compared with various established CHF models as well as the new mechanistic CHF lift-off model recently proposed by the authors. The dependence of CHF on pressure is examined, and it is found that the lift-off model gives a reasonably good prediction of changes in CHF with step changes in the reduced pressure. The R113 and FC-72 boiling curves suggest that a… More >

  • Open Access

    REVIEW

    A REVIEW OF RECENT PROGRESS ON NANO/MICRO SCALE NUCLEATE BOILING FUNDAMENTALS

    J.N. Chunga,†, Tailian Chenb, Shalabh C. Marooc

    Frontiers in Heat and Mass Transfer, Vol.2, No.2, pp. 1-19, 2011, DOI:10.5098/hmt.v2.2.3004

    Abstract Recent research progress in the area of nano/micro scale nucleate boiling is reviewed and an up-to-date summary is provided with a focus on the advances of fundamental boiling physics. This review examines nano/micro scale pool boiling experimental and theoretical/numerical work reported in the open literature. On the experimental side, the topics covered are moving contact line, critical heat flux, boiling curve, nucleation, single bubble boiling cycle, bubble coalescence boiling cycle, heater size effect, nanofluid, and nanoscale-structured heater surface. For the theoretical/numerical work, continuum mechanics modeling of the micro-region and molecular dynamics modeling of the nano-region are included. More >

  • Open Access

    ARTICLE

    FLOW BOILING OF WATER ON TITANIUM AND DIAMOND-LIKE CARBON COATED SURFACES IN A MICROCHANNEL

    Hai Trieu Phanb, Nadia Caneya,†, Philippe Martya, Stéphane Colassonb, Jérôme Gavilletb

    Frontiers in Heat and Mass Transfer, Vol.2, No.1, pp. 1-6, 2011, DOI:10.5098/hmt.v2.1.3002

    Abstract Experiments were performed to study the effects of surface wettability on flow boiling of water at atmospheric pressure. The test channel is a single rectangular channel 0.5 mm high, 5 mm wide and 180 mm long. The mass flux was set at 100 and 120 kg/m2 s and the base heat flux was varied from 30 to 80 kW/m2. Water enters the test channel under subcooled conditions. The sample surfaces are titanium (Ti) and diamond-like carbon (DLC) surfaces having a contact angle of 49° and 63°, respectively. The experimental results show different flow patterns that impact the heat transfer significantly.… More >

  • Open Access

    REVIEW

    CRITICAL HEAT FLUX DURING FLOW BOILING IN MINI AND MICROCHANNEL-A STATE OF THE ART REVIEW

    P. K. Das*, S. Chakraborty, S. Bhaduri

    Frontiers in Heat and Mass Transfer, Vol.3, No.1, pp. 1-17, 2012, DOI:10.5098/hmt.v3.1.3008

    Abstract A state of the art review of critical heat flux during flow boiling through mini and microchannels has been provided based on the open literature. This review mainly examines three aspects, namely the experimental investigations, the available correlations and the state of prediction using those correlations and finally the proposed physical mechanisms as well as the theoretical models. Before discussing the specific literature on microchannels, a brief overview of critical heat flux for pool and flow boiling is provided. The review has been concluded with a summary of the available information on this topic and the need for future research. More >

  • Open Access

    ARTICLE

    A CRITICAL REVIEW OF RECENT INVESTIGATIONS ON TWO-PHASE PRESSURE DROP IN FLOW BOILING MICRO-CHANNELS

    Sira Saisorna,b, Somchai Wongwisesb,c,∗

    Frontiers in Heat and Mass Transfer, Vol.3, No.1, pp. 1-7, 2012, DOI:10.5098/hmt.v3.1.3007

    Abstract Two-phase pressure drop during flow boiling has been studied for several decades. Obviously, the publications available on micro-channels are relatively small compared with those for ordinarily sized channels. Although the use of micro-channels yields several advantages, the pressure drop taking p lace in these extremely small channels is higher than that in the ordinarily sized channels because of the increased wall friction. The knowledge of the two-phase pressure drop characteristics in addition to heat transfer phenomena is essential to the design and evaluation of the micro-systems. In this paper, recent research on the flow boiling pressure drop in micro-scale channels… More >

  • Open Access

    ARTICLE

    A CRITICAL REVIEW OF RECENT INVESTIGATIONS ON FLOW PATTERN AND HEAT TRANSFER DURING FLOW BOILING IN MICRO-CHANNELS

    Sira Saisorna,b, Somchai Wongwisesb,c,*

    Frontiers in Heat and Mass Transfer, Vol.3, No.1, pp. 1-15, 2012, DOI:10.5098/hmt.v3.1.3006

    Abstract A summary of recent research on flow boiling in micro-channels is provided in this article. This review aims to survey and identify new findings arising in this important area, which may contribute to optimum design and process control of high performance miniature devices comprising extremely small channels. Several criteria for defining a micro-channel are presented at first and the recent works on micro-scale flow boiling are subsequently described into two parts including flow visualization and two-phase heat transfer. The results obtained from a number of p revious studies show that the flow behaviours and heat transfer mechanisms in micro-channels deviate… More >

Displaying 1-10 on page 1 of 35. Per Page