Thermal Resistance

Power dissipation is expected to increase exponentially to 150-250 W per chip over the next decade. To manage this large heat output, it is necessary to minimize the thermal resistance between the chip and a heat dissipation unit that the device is attached to. It is therefore important to further improve the thermal performance of thermal interface materials (TIMs), which can be achieved through 1) improvement of the bulk thermal conductivity of TIMs; and/or 2) reduction of interfacial thermal resistances between the TIM and the device and/or TIM and the heat dissipation unit. The latter improvement may be obtained by enhanced physical properties of TIMs (e.g., viscosity or wetting ability) and/or surface modification of the heat dissipation unit or the inactive side of the device. Researchers have tried to take advantage of the high 1D thermal conductivities of graphite fibers, and more recently of carbon nanotubes (CNT), to reduce the thermal resistance between the chip and the h...

Background, aim, and scope The interest in polyethylene terephthalate (PET) recycling is quite recent, but it has been growing steadily over the past few years. In this context, the aim of this paper is to assess the eco-profile, the energy savings and the environmental benefits of the use of recycled raw materials to manufacture products for thermal insulation of buildings in Italy (i.e., PET bottles post-consumer). Materials and methods The life cycle analysis is developed according to ISO 14040/44. In this paper, based on the LCA, the main types of environmental impact of a thermal insulation product have been outlined. This study is specifically focused on polyester nonwovens, produced by a company located in Italy. The cradle-to-gate life cycle inventory is performed for the mass of product needed to give a thermal resistance R of 1 (m2 K/W). The calculation of the impacts is done with SimaPro software. With an environmental product declaration-oriented approach, a set of impact categories is used for the classification and characterisation of the life cycle impact assessment. Results The results of the impact assessment for 1m2 K/W of thermal insulation panels made with recycled PET are then compared with similar products made with virgin PET. The lower impact associated with the recycled PET for each category is underlined: the percentage reduction is around 46% in the GWP category. In the production process, the fiber-spinning phase results as the most relevant in terms of energy consumption. In addition, the energy saved when applying the thermal insulation in a building is estimated at 87 MJ/m2 per unit area per year in Rome. All the energy used during the production of a thermal insulation panel is recovered in about 2 years. Conclusions The product shows significantly low environmental impacts thanks to the use of non-virgin PET, thus maintaining high mechanical and physical properties. If the recovery of PET from separate waste collection in Italy increases, this would reduce the share of waste PET purchased from foreign countries and would therefore reduce further the impact of transports for the production of the thermal insulation panel under investigation.

Our work, during this research and development project, consists of valuing the eco-design,
thermal and energy performance qualities of the MPC (Confined Stone Wall) technology at
the building level according to the climatic zones in Morocco, respecting Moroccan thermal
building regulations (RTCM). We have chosen to treat the example of house in Marrakech by
performing thermal and dynamic simulations by BINAYATE and CAMSOL software to
assess the conformity of the construction with the RTCM