http://www.wseas.us/e-library/conferences/2007athensmech/papers/565-198.pdf

New temperature dependent thermal conductivity data for water-based nanofluids

Many recent advances in thermoelectrics have focused on the nanoscale engineering of materials for higher figure of merit (Z) A thermoelectric generator using these thin-film materials can present new challenges due to its inherently large temperature gradient, but also correspondingly larger generated power if the heat can be managed In such cases performance is expected to be limited as much by the heat sink as by intrinsic material properties New criteria for optimizing the generated power density of devices in this regime are discussed here The effects of future material improvements on performance are studied, with the surprising result that optimizing material Z is not the best strategy for optimizing efficiency or power in this regime The theory is tested with a numerical solution of the Onsager relations This work was supported by the ONR

Optimization of Heat Sink–Limited Thermoelectric Generators

In the heat industry, design of the best-fitting heat exchanger in energy-converting systems has gained vital importance. In addition to fitness, the time needed to design an exchanger is also of g...

Determination of the Optimum Geometry of the Heat Exchanger Body Via A Genetic Algorithm

SUMMARY

Protection against fire for reinforced concrete constructions is of great importance worldwide. There is a general perception that concrete structures are incombustible and thus, they have good fire-resistance properties. In a real fire incident, however, concrete can be subjected to excess temperatures causing severe spalling and serious damage to concrete structures with significant economic cost and high potential risk to human life safety. Although a variety of fire-protection methods exist, there is always a need for the development of new materials with improved thermophysical properties and low cost. Inorganic polymeric materials are promising from this point of view. They are incombustible, combining excellent physical, chemical, mechanical and thermal properties with low production cost and significant environmental benefits. In this work, the thermophysical properties of ferronickel slag-based inorganic polymeric materials are studied. The results from the laboratory scale experiments are promising and indicative of the large-scale behavior of material. The effectiveness of this material has to be proved in large-scale experiments at higher temperatures simulating several severe fire scenarios as well as under all kinds of mechanical loading before concluding for its applicability as a fire protection system. Copyright © 2012 John Wiley & Sons, Ltd.

Inorganic polymeric materials for passive fire protection of underground constructions

Comparison of swimming pools alternative passive and active heating systems based on renewable energy sources in Southern Europe

Before dealing with the application of the Boundary Element Method (BEM) to heat transfer problems we shall summarize the basic theory of heat conduction. It is known from experience that heat flows from the hotter parts of a body to the cooler. The mechanisms responsible for this phenomena are conduction, radiation and convection. Since we are concerned in this paper exclusively with solid bodies, convection only intervenes through boundary conditions in solid-fluid interfaces. Radiation is usually negligible, except eventually when setting up boundary conditions.

H. L. G. Pina

Papers

Heat Transfer Applications