Measurements were made of the flow field structure and the near field parameters of a jet exhausting from a sonic nozzle with a 1.27 cm exit diameter. Compressed air was used for obtaining stagnation pressures up to ~ 5 atmospheres. The jet exhausted vertically from a settling chamber into an acoustically insulated room and through an insulated duct out through the roof. Measurements were made ...

Most buildings require power produced by fossil fuels, the extraction and consumption of which contaminate our environment. The Virginia Center of Basic and Applied Science (CBAS, INC) constructed a building in a remote forested area as a plant and fish nursery (and living space for staff) to be operated by solar electrical power. Comfortable summer interior temperature is facilitated by an ope...

Free-convection flow through a two-dimensional rectangular box having openings at opposite corners on the vertical walls is investigated numerically, using a commercial Computational Fluid Dynamics (CFD) software package. Convection is induced when the box's ceiling or its floor is imposed with a temperature that is different to that of the ambient fluid, while all other walls are insulated. Th...

The article compares the climate conditions in an excavation with thermally insulated roof and sidewalls to when such insulation is absent. analysis of temperatures presented consisted limiting heat transfer from rock mass heading one Polish coal mines. It widely believed that thermal sidewalls, through which fresh air supplied, can substantially improve conditions. article’s objective evaluate...

This paper presents an overview of observed distresses on low slope roofing systems collected for the Building Envelope Life Cycle Asset Management (BELCAM) project. The data include over 14,000 visible distresses from 600 roofs from seven different climatic regions across Canada. The distresses encountered for built up roofs, modified bituminous roofs and a limited number of single-ply roofing...

The use of green roof is a great choice in case climate change mitigation and reduction urban heat islands. Positive aspects roofs during winter or the whole year round balance are often overlooked. surface highly insulated flat overcooled night by long wave sky radiation. This radiative cooling increases thermal losses that reduced existence additional layers. composition layers also have thei...

Gas-insulated substations (GIS) have different specifications in proportion to air-insulated substations. Transformer failures related to lightning and switching are often reported in the gas insulated substation (GIS). This problem is the voltage magnifications due to reflections of switching and lightning surges at various junctions within the GIS. thereby overvoltages in GIS are more importa...

Hybrid Photovoltaic Thermal (PVT) collectors are an emerging technology that combines PV and solar thermal systems in a single solar collector producing heat and electricity simultaneously. The focus of this thesis work is to evaluate the performance of unglazed open loop PVT air system integrated on a garage roof in Borlänge. As it is thought to have a significant potential for preheating vent...