Double-click on the Setup icon and follow the on-screen instructions. Overview Interactive Heat Transfer (IHT) is a general-purpose, non-linear equation solver with an accompanying library of built-in heat transfer correlations and thermophysical property functions. This Guide provides an overview of the essential features of the software by considering several simple examples. The basic use of IHT can be quickly mastered, allowing students and instructors to save significant time, reduce mistakes, perform interesting parametric sensitivity studies quickly and accurately, and produce plots that can be exported to reports and homework solutions. Example 1 may be read prior to reading the text. Example 2 may be performed while reading Chapter 2.
Interactive Heat Transfer V3.0
Example 3 may be performed in conjunction with Chapter 7. Basic Functions and Use of IHT The essential value of IHT is to enable users to easily solve heat transfer problems as well as problems in many other fields of engineering. The unique features of IHT allow users to increase their productivity by focusing on the correct problem formulation, rather than spending time on the more mundane aspects of a problem s solution. Several simple examples will illustrate the power and easeof-use of IHT. Before we solve a heat transfer problem, we begin by demonstrating the ease with which IHT may be used to solve sets of coupled algebraic equations. Hence, you may find IHT to be useful in many of your classes.
This calculator can be use to calculate the overall heat transfer coefficient and the heat transfer through a multi-layered wall. The calculator is generic and can be used for metric or imperial units as long as the use of units is consistent.
ME 3440 - Heat Transfer3 Class Hours 0 Laboratory Hours 3 Credit Hours Prerequisite: ME 3410 and Engineering Standing Fundamentals and applications of heat transfer including conduction, convection and radiation. ÊSteady state and transient conduction in one and multi dimensions. Forced and free convection with boundary layer theory. Radiation properties and radiative heat transfer among black and non-black bodies. Calculation of heat transfer rates, heating/cooling times and design of heat exchangers.
Heat transfer through radiation takes place in form of electromagnetic waves mainly in the infrared region. Radiation emitted by a body is a consequence of thermal agitation of its composing molecules. Radiation heat transfer can be described by reference to the 'black body'.
Heat exchangers are typically classified according to flowarrangement and type of construction. The simplest heat exchanger isone for which the hot and cold fluids move in the same or oppositedirections in a concentric tube (or double-pipe) construction. Inthe parallel-flow arrangement ofFigure 18.8(a), the hot and cold fluidsenter at the same end, flow in the same direction, and leave at thesame end. In the counterflow arrangement ofFigure 18.8(b), the fluids enter atopposite ends, flow in opposite directions, and leave at oppositeends.Figure 18.8:Concentric tubes heat exchangers[Parallel flow][Counterflow] Figure 18.9:Cross-flow heatexchangers.[Finned with bothfluids unmixed.] [Unfinnedwith one fluid mixed and the other unmixed] Alternatively, the fluids may be in cross flow (perpendicular toeach other), as shown by the finned and unfinned tubular heatexchangers of Figure 18.9. The twoconfigurations differ according to whether the fluid moving over thetubes is unmixed or mixed. InFigure 18.9(a), the fluid is said to beunmixed because the fins prevent motion in a direction () that istransverse to the main flow direction (). In this case the fluidtemperature varies with and . In contrast, for the unfinnedtube bundle of Figure 18.9(b), fluidmotion, hence mixing, in the transverse direction is possible, andtemperature variations are primarily in the main flow direction.Since the tube flow is unmixed, both fluids are unmixed in thefinned exchanger, while one fluid is mixed and the other unmixed inthe unfinned exchanger.To develop the methodology for heat exchanger analysis and design,we look at the problem of heat transfer from a fluid inside a tubeto another fluid outside.Figure 18.10:Geometry for heattransfer between two fluidsWe examined this problem before inSection 17.2 and found that the heattransfer rate per unit length is given by
Figure 18.11:Counterflow heat exchangerA schematic of a counterflow heat exchanger is shown inFigure 18.11. We wish to know thetemperature distribution along the tube and the amount of heattransferred.18.5.1 Simplified Counterflow Heat Exchanger (With Uniform Wall Temperature)To address this we start by considering the general case of axialvariation of temperature in a tube with wall at uniform temperature and a fluid flowing inside the tube(Figure 18.12).Figure 18.12:Fluid temperaturedistribution along the tube with uniform wall temperatureThe objective is to find the mean temperature of the fluid at ,, in the case where fluid comes in at with temperature and leaves at with temperature . The expecteddistribution for heating and cooling are sketched inFigure 18.12.For heating (), the heat flow from the pipe wall in alength is
OpenFOAM is the free, open source CFD software developed primarily by OpenCFD Ltd since 2004. It has a large user base across most areas of engineering and science, from both commercial and academic organisations. OpenFOAM has an extensive range of features to solve anything from complex fluid flows involving chemical reactions, turbulence and heat transfer, to acoustics, solid mechanics and electromagnetics. More...
Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, thermal convection, thermal radiation, and transfer of energy by phase changes. Engineers also consider the transfer of mass of differing chemical species (mass transfer in the form of advection), either cold or hot, to achieve heat transfer. While these mechanisms have distinct characteristics, they often occur simultaneously in the same system.
Heat conduction, also called diffusion, is the direct microscopic exchanges of kinetic energy of particles (such as molecules) or quasiparticles (such as lattice waves) through the boundary between two systems. When an object is at a different temperature from another body or its surroundings, heat flows so that the body and the surroundings reach the same temperature, at which point they are in thermal equilibrium. Such spontaneous heat transfer always occurs from a region of high temperature to another region of lower temperature, as described in the second law of thermodynamics.
Heat convection occurs when the bulk flow of a fluid (gas or liquid) carries its heat through the fluid. All convective processes also move heat partly by diffusion, as well. The flow of fluid may be forced by external processes, or sometimes (in gravitational fields) by buoyancy forces caused when thermal energy expands the fluid (for example in a fire plume), thus influencing its own transfer. The latter process is often called "natural convection". The former process is often called "forced convection." In this case, the fluid is forced to flow by use of a pump, fan, or other mechanical means.
Heat transfer is the energy exchanged between materials (solid/liquid/gas) as a result of a temperature difference. The thermodynamic free energy is the amount of work that a thermodynamic system can perform. Enthalpy is a thermodynamic potential, designated by the letter "H", that is the sum of the internal energy of the system (U) plus the product of pressure (P) and volume (V). Joule is a unit to quantify energy, work, or the amount of heat.
Heat transfer is a process function (or path function), as opposed to functions of state; therefore, the amount of heat transferred in a thermodynamic process that changes the state of a system depends on how that process occurs, not only the net difference between the initial and final states of the process.
Thermodynamic and mechanical heat transfer is calculated with the heat transfer coefficient, the proportionality between the heat flux and the thermodynamic driving force for the flow of heat. Heat flux is a quantitative, vectorial representation of heat-flow through a surface.[2]
In engineering contexts, the term heat is taken as synonymous to thermal energy. This usage has its origin in the historical interpretation of heat as a fluid (caloric) that can be transferred by various causes,[3] and that is also common in the language of laymen and everyday life.
Thermal engineering concerns the generation, use, conversion, storage, and exchange of heat transfer. As such, heat transfer is involved in almost every sector of the economy.[6] Heat transfer is classified into various mechanisms, such as thermal conduction, thermal convection, thermal radiation, and transfer of energy by phase changes.
The flow of fluid may be forced by external processes, or sometimes (in gravitational fields) by buoyancy forces caused when thermal energy expands the fluid (for example in a fire plume), thus influencing its own transfer. The latter process is often called "natural convection". All convective processes also move heat partly by diffusion, as well. Another form of convection is forced convection. In this case the fluid is forced to flow by using a pump, fan or other mechanical means.
Convective heat transfer, or simply, convection, is the transfer of heat from one place to another by the movement of fluids, a process that is essentially the transfer of heat via mass transfer. Bulk motion of fluid enhances heat transfer in many physical situations, such as (for example) between a solid surface and the fluid.[10] Convection is usually the dominant form of heat transfer in liquids and gases. Although sometimes discussed as a third method of heat transfer, convection is usually used to describe the combined effects of heat conduction within the fluid (diffusion) and heat transference by bulk fluid flow streaming.[11] The process of transport by fluid streaming is known as advection, but pure advection is a term that is generally associated only with mass transport in fluids, such as advection of pebbles in a river. In the case of heat transfer in fluids, where transport by advection in a fluid is always also accompanied by transport via heat diffusion (also known as heat conduction) the process of heat convection is understood to refer to the sum of heat transport by advection and diffusion/conduction. 2ff7e9595c
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