Papers by Keyword: Heat Losses

Abstract: As the energy crisis's impact spreads, energy consumption has emerged as the fundamental impediment to industry's long-term viability. Utilizing and recovering various sources of waste heat can considerably reduce an organization's energy use. Energy conservation is crucial not just for fuel use, but also for the conservation and protection of the global ecosystem. As a result, it is necessary to make a concerted effort to save energy generated by waste heat. This paper aims to develop flue gas as a substitute for wood burning for drying mold at foundry shop of G-7 trading and industrial PLC. Flue gas temperature and velocity were measured at various locations throughout this study, and an analytical computation was done on the flue gas supply system and mold drying chamber. To show what happens within the hot flue gas supply duct and mould drying chamber, Computational Fluid Dynamics (CFD) Ansys software was used. The business benefits by eliminating the usage of wood as a fuel and making the process more cost-effective and environmentally friendly by capturing hot flue gas from the top section of the furnace or chimney and supplying it through duct to the drying chamber to dry the mold. As a result, the negative impact of deforestation will be mitigated, and a favorable working environment will be established.

Abstract: This case study is aimed at simulation of dry floor heating system. Heating pipes are inserted in system boards made of thermal insulation. These boards should be supplemented with spreader plates which are installed under the heating pipes. Impact of different thermal conductivity of spreader plates on useful heat flux and uniformity of temperature field is examined. Heat losses are also investigated. These simulations are performed using software CalA with time steady-state boundary conditions. The results show that the dry floor heating system without spreader plates has very low useful heat flux caused by positioning of heating pipes in the insulation material. On the other hand, use of spreader plates causes significant increase of useful heat flux of this system. The higher heat conductivity of spreader plates is, the higher useful heat flux is. The floor surface temperature is also more uniform and the thermal comfort is better. The minimal thickness of additional heat insulation is determined in order that heat losses are lower than ten percent of total heat flux.

Abstract: The paper presents the problem of windwashing in partitions including air permeable thermal insulations. There are technical solutions, which deliberately accept the filtration of air in the insulating layer, guided by the necessity of possible drying of building materials. Some scientific papers even suggest that the air infiltration decrease the heat losses through ventilation. In result there occur heat losses in building heat balance which are underestimated and therefore difficult to take into account during calculations. Heat changes on the inner surface of the building partition occur with a delay to the initiation of the wind. However, even the short-term local wind speed loads on thermal insulations result in temperature decreasing and therefore possible condensation on the inner surface of the building partition. The article presents laboratory measurements of air permeability of loose mineral wool and laboratory investigation of the impact of air filtration on heat transfer in lightweight partitions filled with loose thermal insulation.

Abstract: The trend in the components of residential buildings is low energy demand buildings in relation to the minimum costs spent by users for their operation. The main aim of their construction is to improve the energy economy of buildings, to reduce the environmental load in energy consumption, to improve the quality of the interior, to ensure the minimum cost level in the operation of buildings and their maintenance in the life cycle. The consequence of increased energy prices and the possible implementation of tax policies in the countries of Europe is more frequently designing and implementing energy self-contained buildings. This means that energy necessary for the general use of a building can be produced in it to certain extent. The concept of such buildings is not only in high quality heat insulating properties, but also in suitable installed devices utilizing alternative sources. The objective indicator of saving and proof of the required level of a building is an analysis of its real energy consumption. The paper analyzes the energy consumption in a specific house which, in the design phase, met the criteria for designing a nearly zero energy building. The analyzed building has a high thermal protection and uses photovoltaic energy as an alternative source. The main aim is to evaluate the concept of the designed nearly zero energy building and to assess it in relation to the really consumed energy.