Negative differential thermal resistance (NDTR) can be generated for any one-dimensional heat flow with a temperature-dependent thermal conductivity. In a system-independent scaling analysis, the general condition for the occurrence of NDTR is found to be an inequality with three scaling exponents: n1n2 < −(1 + n3), where n1 ∈ (−∞,+∞) describes a particular way of varying the temperature differ...

Thermal death of cancerous cells may be induced by radiating single-walled carbon nanotubes (SWNTs) selectively attached via functionalization to the targeted cells. A distribution of SWNTs inside cancerous cells, on their surface, or in the inter-cellular fluid may occur during this treatment process. This work applies a random walk algorithm to calculate the effective thermal conductivity of ...

where ∆T and q are the temperature drop and heat flux across the interface. Predicting the thermal boundary resistance of semiconductor/semiconductor interfaces is important in devices where phonon interface scattering is a significant contributor to the overall thermal resistance (e.g., computer chips with high component density). Such predictions will also lead to improvements in the design o...

Abstract A current global effort is being made in order to find solutions that will limit warming. The building sector responsible for the highest share of total energy consumption, which requires continuous development strategies increase buildings efficiency. Considering high emissions generated by buildings, improving performance can significantly slow down key point developing reduce consum...

New European product standards now include a mandatory requirement for manufacturers to declare the temperature-dependent thermal conductivity for each insulation used in building equipments and industrial installations. For pipe insulation systems, the measurement is usually performed by a standard pipe test method, in which the value on a large temperature range is integrated to reduce temper...

This paper reports on the dissipation of heat generated by a high power LED array using piezoelectric fans. Both numerical and experimental studies were carried out to evaluate the heat dissipation efficiency of high power LED package operating under multiple vibrating fans. Two vibrating fans were vertically oriented to the LED package and arranged according to configuration A (for edge to edg...

Bond wire lift-off will cause an increase of remaining wires’ power dissipation, which usually is ignored for healthy modules. However, only partial dissipation transfers through thermal path from junction to case, lead overestimate the whole collector emitter pole and underestimate calculated resistance using proportion temperature difference dissipation. A FEM model established show change he...

This paper aims at solving the problem of explosion proof in measurement of thermal gas flow using electronic sensor by presenting a new type of flow sensor by optical fiber heating. A measuring unit based on fiber Bragg grating (FBG) for fluid temperature and a unit for heat dissipation are designed to replace the traditional electronic sensors. The light in C band from the amplified spontaneo...

heat and mass transfer, in this paper, is considered in one-row heat exchanger, that fins are hotter than air flow and water is added to fins. related governing equations are derived by analyzing a two-dimension model in a unique cell of a heat exchange. these equations are numerically solved by finite difference method. heat transfer and efficiency under partially wet surface are calculated by...