1,721,002 research outputs found
X40B0T01 Semi-infinite Cartesian body initially at uniform temperature other than zero and in perfect contact with a thermally insulated high-conductivity surface layer with zero initial temperature
No full textEigen-periodic-in-space surface heating in conduction with application to conductivity measurement of thin films
No full textA two-dimensional heat conduction problem in Cartesian coordinates subject to a periodic-in-space
boundary condition is analyzed by the Green’s functions approach. It is pointed out that when the frequency of the spatial periodic heating equates one of the natural frequencies (eigenvalues) of the system,
the solution of the 2D heat conduction problem can be written down very simply as the product of the
periodic surface condition (termed the ‘‘eigen-periodic”) by the solution of a 1D fin problem along the
nonhomogeneous direction. This result suggests a novel and simple algebraic equation for determining the thermal conductivity of thin films placed on substrates under steady state conditions. High space frequencies of the sinusoidal heating, larger than the deviation frequency, are used to make negligible the thermal deviation effects due to the presence of the substrate
X10B1T0 Semi-infinite Cartesian body with step change in boundary temperature and zero initial temperature
No full textX12B10T0 Slab with jump in temperature at one boundary, zero heat flux at other boundary and initially at zero temperature
No full textMixed Boundary Conditions in Heat Conduction
No full textIn mixed boundary value (MBV) problems, the nature of the boundary condition can change along a particular boundary (finite, semi-infinite or infinite in length), say from a Dirichlet condition to a Neumann condition. Most MBV problems are solved using classical techniques such as separation of variables (domain of limited extent) or transform methods (domain of semi-infinite or infinite extent) which lead to dual or triple integral equations. Also, they are usually solved when a steady state condition is reached [1]. In authors’ knowledge, the only exception is the paper by Sadhal about solids with partially contacting interface [2]. In this work we deal with both steady state and transient MBV problems which are solved as inverse heat conduction (IHC) problems [3] using Green’s functions [4] and superposition in space and time
X40B0T10 Semi-infinite Cartesian body initially at zero temperature and in perfect contact with a thermally insulated high-conductivity surface layer with uniform initial temperature other than zero
No full textX11B10T0 Slab with jump in temperature at one boundary, zero temperature at other boundary and initially at zero temperature
No full textInverse Heat Conduction using Numerical Green’s Function Equation
No full textA transient, multi-dimensional, heat conduction problem can be solved using analytical (exact and approximate) and numerical methods [1, 2]. They are the first stage of solution procedures for solving the inverse heat conduction problems (IHCPs) [3]. Among them, the numerical approximate form of the Green’s function equation based on a heat-flux formulation can be relevant in investigation of the IHC problems because it gives a convenient expression for the temperature in terms of the unknown heat flux components. Also, it states that the temperature or heat flux computation employs only one basic “building block” solution, which is the solution of a direct problem subject to a partial heating by a boundary condition of Neumann type. This solution was derived by exact analysis using Green’s functions in Ref. [4]
Intrinsic Thermocouple Problem using Unsteady Surface Element Method
No full textA boundary discretization technique called the Unsteady Surface Element method (USEM) is applied to a model of a thermocouple wire attached to a thin disk. Green’s functions are then used to develop the integral equations for the wire and the disk. The model can be used to evaluate transient and steady state responses for many types of heat flux measurement devices, including thin skin calorimeters and circular foil heat flux gages. The utility of the error correction is demonstrated with the application of the inverse heat conduction problem (IHCP) to the determination of the unknown heat flux in a short-flash solar heating process. It is shown that errors in the temperature measurements can range from just a few degrees Celsius to about 100 °C
X20B1T0 Semi-infinite Cartesian body with jump in boundary heat flux and zero initial temperature
No full text- …
