This work presents the results of a set of steady-state numerical simulations about heat transfer in hollow blocks in the presence of coupled natural convection,conduction and radiation.Blocks with two air cells deep ...This work presents the results of a set of steady-state numerical simulations about heat transfer in hollow blocks in the presence of coupled natural convection,conduction and radiation.Blocks with two air cells deep in the vertical direction and three identical cavities in the horizontal direction are considered(typically used for building ceilings).Moreover,their outside horizontal surface is subjected to an incident solar flux and outdoor environment temperature while the inside surface is exposed to typical indoor environment conditions.The flows are considered laminar and two-dimensional over the whole range of parameters examined.The conservation equations are solved by means of a finite difference method based on the control volumes approach,relying on the SIMPLE algorithm for what concerns the coupling of pressure and velocity.The effects of the number of cells in the horizontal direction and the thermal conductivity on the heat transfer through the alveolar structure have been investigated.The results show that the number of holes has a significant impact on the value of the overall heat flux through the considered structure.展开更多
Reusing recycled waste materials in buildings is gaining more and more attention for what it offers economic,environmental,and energy benefits;and many researchers are nowadays working on producing new sustainable con...Reusing recycled waste materials in buildings is gaining more and more attention for what it offers economic,environmental,and energy benefits;and many researchers are nowadays working on producing new sustainable construction materials incorporating recycled wastes.In this scope,this work uses an experimental approach aiming at understanding the effect of incorporating Expanded Polystyrene(EPS)beads in concrete and proposing thermally improved concrete mixtures for the production of hollow blocks in Lebanese constructions by substituting fine aggregates with recycled products such as EPS in order to promote their insulating properties.Three different diameters of EPS beads(2 mm~3 mm,3 mm~4 mm and 4 mm~5 mm)are studied with different volumetric ratios(20%,40%,60%and 80%)in order to investigate the effect of EPS on the thermal properties of concrete.The results showed that the only the percentage of incorporated EPS beads impacted the thermal performance of the concrete mixtures while the EPS diameters have a negligible effect on the thermal properties of the concrete samples.展开更多
文摘This work presents the results of a set of steady-state numerical simulations about heat transfer in hollow blocks in the presence of coupled natural convection,conduction and radiation.Blocks with two air cells deep in the vertical direction and three identical cavities in the horizontal direction are considered(typically used for building ceilings).Moreover,their outside horizontal surface is subjected to an incident solar flux and outdoor environment temperature while the inside surface is exposed to typical indoor environment conditions.The flows are considered laminar and two-dimensional over the whole range of parameters examined.The conservation equations are solved by means of a finite difference method based on the control volumes approach,relying on the SIMPLE algorithm for what concerns the coupling of pressure and velocity.The effects of the number of cells in the horizontal direction and the thermal conductivity on the heat transfer through the alveolar structure have been investigated.The results show that the number of holes has a significant impact on the value of the overall heat flux through the considered structure.
文摘Reusing recycled waste materials in buildings is gaining more and more attention for what it offers economic,environmental,and energy benefits;and many researchers are nowadays working on producing new sustainable construction materials incorporating recycled wastes.In this scope,this work uses an experimental approach aiming at understanding the effect of incorporating Expanded Polystyrene(EPS)beads in concrete and proposing thermally improved concrete mixtures for the production of hollow blocks in Lebanese constructions by substituting fine aggregates with recycled products such as EPS in order to promote their insulating properties.Three different diameters of EPS beads(2 mm~3 mm,3 mm~4 mm and 4 mm~5 mm)are studied with different volumetric ratios(20%,40%,60%and 80%)in order to investigate the effect of EPS on the thermal properties of concrete.The results showed that the only the percentage of incorporated EPS beads impacted the thermal performance of the concrete mixtures while the EPS diameters have a negligible effect on the thermal properties of the concrete samples.