Authors:Pavol Fedorčák, Danica Košičanová, and Daniel Čurka
, (last visited 15 February 2012)
Čurka D., Molotta M. Using solar energy to drive an absorption refrigeration unit with an output of 10 kW, (in Slovak), Medzinárodná konferencia Vykurovanie , Stara Ľubovňa, Slovakia, 28
. , Hamard , E. , Cothenet A.
Measuring the water absorption of recycled aggregates, what is the best practice for concrete production?
Construction and Building Materials , Vol. 123 , 2016 , pp. 690 – 703
Sustainability and scarcity in resources are the two major issues to be dealt within the present scenario by effective utilization of alternative materials. In this present study, an attempt has been taken to study the effect of supplementary materials such as fly ash and silica fume as a partial replacement to cement and steel slag and M-sand as a replacement to river sand on strength and durability of concrete. In this study, concrete specimens were prepared based on five different mixes by varying the percentages of these supplementary materials. Various mechanical properties like compressive strength, split tensile strength and flexural strength were performed to ascertain the mix with optimum levels of replacement of supplementary materials for cement and fine aggregate. Durability property like water absorption test was performed on the mix with optimum values of strength. Results revealed that mix with higher percentages of steel slag, optimum level of silica fume and fly ash have shown higher strength and lesser permeability in concrete.
In this paper phase change materials are presented, as effective thermal energy storage due to their great latent heat storing possibility. The main substance used for thermal energy storage purposes is water. Storing the energy with water is not that effective as with phase change materials, because the temperature of water has to change, and it worsen the heat exchange intensity. On the other hand, with phase change materials the temperature of the material does not have to change due to the latent heat storage possibilities. A buffer tank with two pipe coils filled with phase change materials is investigated with the aim to reduce the storage volume. An own thermodynamic model, a CFD simulation and an experimental system are presented. The models could be validated and the process of phase change could be examined with a life-size thermal energy storage system in the laboratory of the department. The performance of heat absorption and release of the phase change material could be calculated in the function of inlet water temperature and mass flow.