Heat transfer measurements are conducted under conditions of forced convection of the saturated liquid parallel and countercurrent to the flow. Porous medium, forced convection, fluent, heat exchanger, laminar flow. Heat transfer characteristics of porous media nasaads. Heat and mass transfer through a porous media of mhd. Experimental investigation of heat transfer through porous material. Convection heat transfer in porous media using ansys. Heat transfer analysis over porous surface is of much practical interest due to its abundant applications.
Figure 16 schematic of a porous media burner used for household heating 37 figure 17 a detailed view inside the heat exchanger elements b heat exchanger 38 figure 18 porous burner heat exchanger thermal efficiency relating to lhv 40 figure 19 schematic diagram of experimental apparatus 41. There is a tradeoff between the heat transfer and pressure drop in the design of enhanced heat exchangers. Heat and moisture transfer in a rectangular cavity partially filled with hygroscopic porous media. An investigation was conducted regarding the relative effects of conduction and convection in a saturated porous medium. K k any material which consists of solid matrix with an. The first very compact heat exchanger is located at the exit of the region c, and second one is located in the mantle of the pm combustor itself. Design and modeling of a heat exchanger for porous. Pdf an investigation into the effect of porous medium on. Heat transfer between the solid matrix, and the fluid within porous media is supported since ansys cfx release.
Recent advances in hightechnology fields such as elec. Part 2 deals with fluidsolid transfer processes, both in cases where the interface is small and in cases where it is large, as well as liquidliquid transfer processes. Subsequently, the revscale lb method for fluid flow and singlephase heat transfer in porous media and the lb method for solidliquid phasechange heat transfer are discussed in detail. Porous heat exchangers are receiving considerable attention as their application can lead to high heat transfer rates usually within a limited footprintwhich could be of significant importance in some engineering applications including aircooled condensers wherein heat exchanger size determines the fan or the cooling tower size. Sep 30, 2017 in this paper, the study was focused on a double flow platefin heat exchanger pfhe whose heat transfer element was offset staggered fin. In this study, convective heat transfer in a porous flat plate channel flow is simulated by a direct numerical method. Experimental investigation of heat transfer through porous material heat exchanger 53 porous material is a solid containing void spaces pores, connected or unconnected, dispersed within it in either a regular or random manner. Numerical simulations have been carried out to investigate the thermodynamic characteristics of a fullsize pfhe via the porous media approach. The comparison of the data obtained is hampered by. The mixings are mainly due to molecular diffusion of heat as well as the mixing caused by the nature of the porous medium. Review of convection heat transfer and fluid flow in porous media with nanofluid. Heat transfer enhancement in shellandtube heat exchangers.
Introduction to fluid flow and heat transfer in porous media. Porous medium, forced convection, fluent, heat exchanger. The test section was consisted of flow channel 38 mm. Download pdf ous media, dynamic modeling of convective transport through porous media. Us20080099191a1 parallel flow heat exchangers incorporating. Heat transfer augmentation is accomplished using porous media silica particles on the lowside 12. In this work, the effects of electrical double layer edl near the solid liquid interface, on three dimensional heat transfer characteristic and pressure drop of water flow through a rectangular microchannel numerically are investigated. Porous media compact heat exchanger unitexperiment and.
This paper presents a brief discussion on the application of using porous media to heat exchangers by means of heat transfer enhancement. Numerical simulation of a platefin heat exchanger with. Influence of heat transfer process in porous media with. The cost of the heat exchanger is equal to or even greater than the cost of the boilers.
The purpose of this chapter is to outline a rigorous theoretical approach to the problem of drying granular porous media. Proceedings of the 4th international conference of fluid flow, heat and mass transfer ffhmt17 toronto, canada august 21 23, 2017 paper no. This thesis details the process taken for the computational modelling of convective heat transfer in porous media with the objective of improving the accuracy of porous continuum models. However, the term is commonly used to equipment in which two process streams exchange heat with each other. Hi, i am trying to model a heat exchanger using porous media approach in cfx 15.
Goldstein lewis research center summary a general technique has been devised for obtaining exact solutions for the heat transfer behavior of a twodimensional porous cooled medium. Aug 24, 2012 heat transfer through porous media takes advantage of the fact that governing equations used for describing various flow and transport phenomena in porous media are all generally based on the same form of mass andor energy conservation laws. In contrast to the parallel flow heat exchanger, the counter flow heat exchanger can have the hottest coldfluid temperature greater than the coldest hotfluid temperatue. Porous heat exchangers for continuous flow helium cryostats. Experimental investigation of heat transfer through porous. An investigation into the effect of porous medium on. Combined heat and mass transfer in porous media heat. Pdf on feb 14, 2011, ehsan mohseni languri and others published heat transfer in porous media find, read and cite all the research you need on researchgate. Principles of heat transfer in porous media download. Entropy generation minimization of shell and tube heat. Principles of heat transfer in porous media springerlink. In porous flow if reynolds number increases the rate. When the porous media is located at the center of the tubes, the pressure drop prevailed over the. Convection heat transfer in porous media using ansys fluent.
Thermal applications of open cell metal foams burhan ozmat, bryan leyda and burt benson erg, materials and aerospace corporation 900 stanford avenue, oakland, ca 94608 abstract. Heat and mass transfer in porous media is central to many applications involving industrial devices chemical engineering, heat exchangers, nuclear reactor, etc. Convection in porous media convection heat transfer. Heat and mass transfer in drying of porous media request pdf.
Heat exchangers jordan university of science and technology. Heat transfer february, 1991 experimental determination of spectral transmittance of porous cerium dioxide in the range 9001700 nm. Porous media based phase separation in condensing heat. Of central importance is the fact that the heat flux depends on the relative orientation of the velocity and temperature gradient vectors. Analysis of a compact heat exchanger using porous media. Bidirectional porous media phase change heat exchanger. Comparison of different porous structures optimized porous media based heat exchanger surface. The porous layer inserted at the core of the conduit. Heat transfer in porous media 635 the mixing caused by the nature of the porous medium. Heat transfer enhancements in heat exchangers fitted with. The existence of porous media in the flow path, improve the matrix of thermal conductivity and effective flow thermal capacity and also matrix of porous solid increase radiation heat transfer, especially in two phase flow gas.
Viskanta heat transfer laboratory, school of mechanical engineering, purdue university, west lafayette, in 47907, u. The thermal properties, the porosity and the wetting characteristics of the porous materials are judiciously chosen so that efficient conceptual design of a condensing heat exchanger for space systems using porous media mohammad m. On modelling of compact tube bundle heat exchangers as. Simultaneous application of nanofluid and porous media in a counterflow doublepipe heat exchanger is studied in order to enhance its heat transfer with minimum power increase.
Porous media compact heat exchanger unit experiment and. Porous media have a large contact surface with fluids, which can enhance the heat transfer process. Experimental work included the design of a tube in tube heat exchanger with the dimensions of. Results for heat transfer area versus duty, temperature approach versus heat transfer area, and, effectiveness versus duty are presented. The results of experimental determination of the volume heat transfer coefficient in porous media are summarized in figure 6 the numerals from 1 to refer to the published papers. This site is like a library, use search box in the widget to get ebook that you want.
Shellandtube heat exchangers are commonly used in oil refineries and other large chemical processes. Convection heat transfer in porous media have many theoretical and practical. Mass conservation darcy flow model and the forchheimer modification first law of thermodynamics second law of thermodynamics forced convection natural. In this model, two separated fluids at different temperatures flow through the heat exchanger, one through the tubes tube side and the other through the shell around the tubes shell side.
Thermal radiation, convection, and conduction in porous. Bidirectional porous media phase change heat exchanger mit. Heat transfer enhancements in heat exchangers fitted with porous media part i. Natural convection solidliquid phase change in porous media. Natural convection solidliquid phase change in porous media c.
This heat exchanger uses evaporation to transfer heat in one direction and dropwise condensation to transfer heat in the other direction. Ganesh charlotte, nc, usa quest global this paper discusses how the heat exchanger cooler is modelled using cfd computational fluid dynamics as a porous medium and the associated boundary conditions. Heat and mass transfer through a porous media of mhd flow of nanofluids with thermal radiation, viscous dissipation and chemical reaction effects b. Rad et al 3 investigated the influence of using porous media in a shell and tube heat exchanger. Forced convection, heat exchanger, dimensional analysis, calibration.
Porous media compact heat exchanger unit experiment and analysis article in experimental thermal and fluid science exp therm fluid sci 282. Analytical method for steady state heat transfer in twodimensional porous media by robert siege1 and marvin e. Yakovlev2 1department of mechanical engineering, worcester polytechnic institute, ma, usa. In evaporation mode, liquid supplied to minichannels under a copper porous media move into the media due to capillary forces. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed. A 2d model of a triple layer electromagnetic heat exchanger with porous media flow ajit a. Heat and mass transfer in wet porous media are coupled in a very complicated way. Pdf i using porous material for heat transfer enhancement in. Cfd heat exchanger simulation with porous media as surrogate. Ansysfluent heat exchanger tutorial computational fluid. As an example a compact tube bundle heat exchanger with oval shaped tubes was chosen.
Based on the transport mechanism of heat and mass transfer and by using the minimum gradient theory for unsaturated flow in capillary porous media, a mathematical model was developed for heat and. A 2d model of a triple layer electromagnetic heat exchanger. The effects of porosity and dimensions of these media on the heat. Pdf in this paper, a detailed numerical investigation of twodimensional laminar. Cfd simulations were performed to predict convective heat transfer resulting from forced flow through highly conductive porous blocks. Using porous media to improve the performance of a wavytube. Design and modeling of a heat exchanger for porous combustor. The code twoporflow is developed to simulate single and twophase flow including heat transfer and phase change in multimicrochannel devices. In present work experimental investigation of heat transfer enhancement in double pipe counter flow heat exchanger with insert metallic pad inner tube. This article investigates the entropy generation rate in shell and tube heat exchanger with porous medium inserted inside the tubes.
Convection in porous media, 4th edition, provides a userfriendly introduction to the subject, covering a wide range of topics, such as fibrous insulation, geological strata, and catalytic reactors. These results have confirmed the high effectiveness of porous heat exchangers, even in comparison with chambertype heat exchangers. Counter flow heat exchangers are the most efficient of the three types. Using porous materials in the fluid flow is one of the passive methods to increase heat transfer in heat exchangers. Porous media simplified simulation of single and two. The presentation is selfcontained, requiring only routine mathematics and the basic elements of fluid mechanics and heat transfer. Heat exchanger counterflow is made of two, serially connected exchangers. Introduction to heat and mass transport in porous media nato sto. This work investigates heat transfer enhancement for a flow in a pipe or a channel fully or partially filled with. Thermalhydraulic performance of small scale microchannel. Further development can be expected in application of heat exchangers on the basis of porous. The rapid growth of literature on convective heat and mass transfer through porous media has brought both engineering and fundamental knowledge to a new state of completeness and depth. Analytical expressions relating such properties to basic structural.
Analytical method for steady state heat transfer in two. Lattice boltzmann methods for singlephase and solid. A numerical simulation has been carried out to investigate the heat transfer enhancement in a shellandtube heat exchanger using a porous medium inside its shell and tubes, separately. Thermal radiation, convection, and conduction in porous media contained in twodimensional vertical cavities j. Pdf heat and mass transfer in granular porous media. In this paper planning required for evaluating performance of porous material, i. Additionally, cooling of the preheating zone is donein order to prevent flame propagation. Convection heat transfer in porous media has been studied extensively for over 150 years now 12.
Convective heat tranfer is the result of fluid flowing between objects of different temperatures. This work investigates heat transfer enhancement for a flow in a pipe or a channel fully or partially filled with porous medium. While emphasizing a basic understanding of heat transfer in porous media, this book does not ignore the need for predictive tools. Low heat transfer coefficient from smoke gasses on tubes requires a large heat transfer surface, creating the need for the large dimensions of the heat exchanger.
A semiempirical model for porous media heat exchanger design. Heat transfer through porus media is very effective and efficiently. The flow channel can be seen in heat exchanger with porous media cfd online discussion forums. Pdf numerical study of sulfur trioxide decomposition in. Porous medium is defined as a material volume consisting of solid matrix with an interconnected void. Planning of experimentation for performance evaluation of. The basics, concepts, governing relationships, and existing models have been investigated and modeled for heat transfer in porous media using gambit2.
Using porous media to improve the performance of a wavytube heat exchanger heat transfer increase has been always the industries aim. The platefin heat exchanger includes a first fluid pathway running along a first axis, a second fluid pathway running along a second axis perpendicular to the first axis, and a blocker bar having an inlet face and an outlet face. Jun 03, 2008 a numerical and experimental study of heat and mass transfer has been carried out for an energy recovery ventilator with a porous media heat exchanger. Flow in porous media have revealed the darcy law porous medium.
Heat transfer through porous materials has gained significance in industrial applications based research. Porous media based phase separation in condensing heat exchanger for space systems 2006012275 one of the key elements of a recently proposed composite porous media condensing heat exchanger for space systems is to utilize capillary pressure for collecting and removing water from the condensing unit. The structure of the solid matrix varies widely in shape. Pdf nonnewtonian fluid heat transfer in porous media. Conceptual design of a condensing heat exchanger for space. A computational tool and a methodology for steady state heat exchanger simulations of recuperated gas turbines and aeroengines have been developed. Porous media based phase separation in condensing heat exchanger for space systems 2006012275 one of the key elements of a recently proposed composite porous media condensing heat exchanger for space systems is to utilize capillary pressure for. Heat transfer in porous media 227 brazilian journal of chemical engineering vol. Click download or read online button to get principles of heat transfer in porous media book now.
Received 21 february 1987 and in final form 29 may 1987. Abandoned application number us11794,970 inventor michael f. Parametric study capability enables a fast characterization of the actual geometry porous media replaces complex sheet metal structurein full heat exchanger simulation. Us9279626b2 platefin heat exchanger with a porous blocker. On modelling of compact tube bundle heat exchangers as porous. These so called pores may contain a variety of fluids such as air, water, oil etc. The results of experiments carried out at helium and nitrogen temperatures are presented. Three different waste metal chips made of copper, aluminum, and mild steel are used as porous medium. Numerical study of sulfur trioxide decomposition in bayonet type heat exchanger and chemical decomposer with porous media zone and different packed bed designs. The energy recovery ventilator selected for this study has a rotary periodic heat exchanger that can transfer heat and moisture from one air stream to another.
In order to solve this problem fluent software was used. Therefore, from the heat transfer point of view the porous media micro. Greenkorn 22 mentioned the followin g nine mechanisms for most of the mixing. Using porous media to enhancement of heat transfer in heat. A porous medium is a solid with voids distributed more or less uniformly throughout the bulk of the body.
In the porous domain setting, for the solid model, i would like to heat transfer in porous media cfd online discussion forums. To realise a simplified efficient method taking into account the essential physical processes of flow and heat transfer in a microchannel heat exchanger a porous media approach is used. Part 3 considers three media, addressing both liquidsolidsolid and gasliquidsolid systems. Based on the numerical model, the effects of the dynamic viscosity and the locations of the inlet and outlet. In this paper thermal performance including heat transfer and pressure drop through porous material, i.