longitudinal heat conduction is an important parameter in the cryogenic field, especially in cryogenic heat exchangers. in the present work, the parasitic effect of tube wall longitudinal heat conduction on temperature measurement has been studied in cryogenic laminar hydrogen flow. the effects of various parameters such as wall cold end temperature, wall thermal conductivity, gas volumetric fl...

This paper presents the electrothermal simulation of integrated thin film resistors. Both the thermal and electrical problem is tackled by a semi-analytical method, without the need of generating an equivalent distributed network. As the electrical conductivity is temperature dependent, self-heating of the resistor will alterate the current distribution, leading to a non-uniform power dissipati...

Using molecular dynamics simulations, the thermal conductivity of silica-based crystals is found to be a result of two independent thermal transport mechanisms associated with atomic structure. The first mechanism is temperature independent, produces a thermal conductivity on the order of 1 W/mK, and is related to short length scale behavior. It is governed by the silicon coordination, which is...

Copper-Graphite laminate material design has been analysed, and this proposed composite has the ability to enhance heat dispersing more efficiently compared to the traditional high thermal conductivity with weight associated copper and high thermal resistance graphite. A finite element analysis (FEA) is carried out using the material (Cu – Gr) properties to investigate this proof. The design, t...

We present thermal conductivity measurements of micromachined 500 nm thick silicon-nitride Si–N beams suspended between two Si–N islands, in the temperature range from 77 to 325 K. The measured thermal conductivity, k, of Si–N at high temperatures is in good agreement with previously measured values for Si–N grown by low-pressure chemical vapor deposition, but behaves much differently as temper...

We find that the electrical and thermal connectivity in multiwalled carbon nanotube buckypaper can be tuned using a spark plasma sintering (SPS) technique. Elevated SPS temperatures promote the formation of inter-tube connections and consequently impact the electrical resistivity, thermoelectric power and thermal conductivity of the buckypaper. In particular, the electrical resistivity as a fun...

The thermal conductivity of polycrystalline magnesium oxide has been measured over the temperature range from 400 K to 1300 K using a modified guarded-hot-plate design. Three different thicknesses of specimens having 93 % of theoretical density were tested to verify the operation, accuracy, and reproducibility of our apparatus. The measured thermal conductivity ranges from 30 W · m-1 · K-1 down...

A two dimensional deformation due to internal heat source in a thermoelastic solid with microtemperatures under the dependence of modulus of elasticity and thermal conductivity on reference temperature has been studied. A mechanical force of constant magnitude is applied at the free surface of thermoelastic half space. The normal modes technique has been applied to obtain the exact expressions ...

Rate of heat transfer ∂u = (1) −K0 area ∂x where K0 is the thermal conductivity, units [K0] = MLT U . In other words, heat is transferred from areas of high temp to low temp. 3. Conservation of energy. Consider a uniform rod of length l with non-uniform temperature lying on the x-axis from x = 0 to x = l. By uniform rod, we mean the density ρ, specific heat c, thermal conductivity K0, cross-sec...