Search results
Results From The WOW.Com Content Network
The general definition of the heat transfer coefficient is: where: : heat flux (W/m²); i.e., thermal power per unit area, : difference in temperature between the solid surface and surrounding fluid area (K) The heat transfer coefficient is the reciprocal of thermal insulance. This is used for building materials (R-value) and for clothing ...
Refractory metals. Refractory metals are a class of metals that are extraordinarily resistant to heat and wear. The expression is mostly used in the context of materials science, metallurgy and engineering. The definition of which elements belong to this group differs. The most common definition includes five elements: two of the fifth period ...
Let K0 is the normal conductivity at one bar (10 5 N/m 2) pressure, Ke is its conductivity at special pressure and/or length scale. Let d is a plate distance in meters, P is an air pressure in Pascals (N/m 2), T is temperature Kelvin, C is this Lasance constant 7.6 ⋅ 10 −5 m ⋅ K/N and PP is the product P ⋅ d/T.
kg -1 ⋅m -1 ⋅s 3 ⋅K. Dimension. − −. The thermal conductivity of a material is a measure of its ability to conduct heat. It is commonly denoted by , , or and is measured in W·m −1 ·K −1. Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal conductivity.
Refractory. Refractory bricks in a torpedo car used for hauling molten iron. In materials science, a refractory (or refractory material) is a material that is resistant to decomposition by heat or chemical attack and that retains its strength and rigidity at high temperatures. [1] They are inorganic, non-metallic compounds that may be porous or ...
Nusselt number. In thermal fluid dynamics, the Nusselt number (Nu, after Wilhelm Nusselt [1]: 336 ) is the ratio of total heat transfer to conductive heat transfer at a boundary in a fluid. Total heat transfer combines conduction and convection. Convection includes both advection (fluid motion) and diffusion (conduction).
Thermal conduction (power) is the heat per unit time transferred some distance ℓ between the two temperatures. κ is the thermal conductivity of the material. A is the cross-sectional area of the object. ΔT is the difference in temperature from one side to the other. ℓ is the length of the path the heat has to be transferred.
Chilton–Colburn J-factor analogy (also known as the modified Reynolds analogy[1]) is a successful and widely used analogy between heat, momentum, and mass transfer. The basic mechanisms and mathematics of heat, mass, and momentum transport are essentially the same. Among many analogies (like Reynolds analogy, Prandtl–Taylor analogy ...