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Awareness of the thermal conductivity of nanofluids regard to a significant development for use in research,it is necessary with regard to the inability of the analytical and experimental models that presented in most cases, it experimentally thermal conductivity can be measured. In this paper, the design and performance of thermal conductivity of fluids and nanofluidics measurement device without using a Wheatstone bridge is tested. Wheatstone bridge short transient hot wire method has previously been used for construction that requiring complex electronic systems and high power consumption. In this paper, a new method is provided so that no current or voltage is kept constant, but the method of measuring the relative resistance of the copper-clad lacquered with a diameter of 40 microns was used probe is easy to is within reach. The difference between the results of the design references, 1.17% is obtained. In this regard, changes in the magnetic fluid thermal conductivity is studied experimentally. Magnetic fluids are a new class of nanofluids are affected by magnetic fields and their properties can be changed. Fe3O4 magnetic water-based tests for different volume percentages.

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This numerical study forced convective heat transfer ferrofluid within a circular copper tube includes portions of the electromagnetic isolation under an alternating magnetic field is performed. Laminar flow through a tube under uniform and thermal flux passes. Intensifying transfer of particles and velocity increase in the boundary layer using nanoparticles to increase the effect of magnetic field onto more heat transfer, the main goal is. Convection regimens resulting from complex interactions between magnetic nanoparticles were studied under different conditions, with the concentration and volume of different the heat transfer process under different frequencies of the applied magnetic field were studied. Magnetic field effects on the convective heat transfer coefficient at different Reynolds numbers and volume percentages have been studied. Also when the electromagnetic is insulated pipe parts of have been studied and have been compared with the modes without insulation. Increase the frequency and volume fraction of magnetic field, resulting in increased heat transfer were better. Magnetic field at low Reynolds numbers have shown a greater impact. For prove the numerical results evaluated in this research work has been studied experimentally. The results showed that the modeling data were in very good agreement with experimental data.

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In this article, indicators of annual energy intensity 13 residential complexes with different characteristics were evaluated and compared. These features include the type of facade, heating and cooling systems, windows, and separate or shared type gas meters are units available in the complex. Introducing selected complexes, specifications hull, heating and cooling systems as well as the energy used in the study and analysis of energy flows in the complex have been discussed. The data processing methodology for calculating the energy consumption rate index have been studied conglomerate. The indices are calculated energy intensity of buildings and structures with different properties in terms of energy intensity compared. Compare energy intensity indicators show that the use of new energy Mtalh like metal siding board (decorative panels) instead facade, windows UPVC windows instead of metal, instead of single-wall and double glass instead of heaters and boilers as well as the use of semi-centralized heating systems or room in the building's energy intensity has considerably decreased. Also, instead of using a separate gas meter gas meter joint, by influencing the behavior of the occupants of the building and create a financial incentive to reduce energy use saves natural gas consumption and decreasing energy intensity building.