الفهرس 
Thermal Mass Potential for Optimizingthe Building’s Thermal PerformanceOnly 14 pages are availabe for public view
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Abstract
Thermal mass is the ability of material to absorb, store and release thermal energy. In building design, thermal mass is an essential property that should be present in the construction materials. Thermal mass can passively regulates indoor spaces temperatures due to the convective effect of air inside the space which passively comes into contact with exposed thermal mass surfaces. But, to be useful in the building environment, indoor heat absorption and releasing must be at a rate roughly in step with a building’s daily needed heating and cooling cycle. Therefore, thermal mass is much more useful concept if the energy storage can be controlled. Convective heat transfer can be further increased by using mechanical means to create forced convection rather than relying on natural buoyancy forces. Active thermal mass strategies, therefore, describe methods of being able to heat and cool the mass in a controlled manner.
This thesis is divided into two sections: first section concerns the enhancement of passive thermal mass materials by applying alternative construction materials with different thermal properties into an existing educational building. Passive thermal mass is classified according to heat storage into sensible thermal mass and latent thermal mass. While the second section introduces the active thermal mass strategies as a new approach into educational buildings especially school classrooms. It investigates different Active Thermal Mass Strategies (ATMS) to be integrated into the case study through Energy plus simulation tool. The ATMS that have been investigated in this thesis are divided according to thermal mass medium into Thermo-Active Building Structure (TABS) and Thermo-Active Ground Storage Source (TAGS). Moreover, this thesis introduces a new thermal efficiency approach by integrating the ATMS with Phase Change Materials (PCM) as example of latent thermal storage materials and creating a new system namely Hybrid ATM which is consisted of TABS-PCM and TAGS-PCM.
Dynamic thermal modeling for different active thermal mass strategies is presented to accurately determine the classroom thermal performance when it is integrated to ATMS through virtual test environment. The thesis discuses, through simulations, how active thermal mass strategies can be used in buildings to stabilize the indoor temperature and enhance thermal comfort. Simulations procedure is passed through three phases; first phase concerns simulations of alternative integrations of passive thermal mass composite materials, second phase concerns simulations of different active thermal mass strategies and third phase concerns the investigation of ATMS in different alternative facing orientations. Results for a full year simulation are presented and compared to the base case performance.
Results indicate that high thermal mass composite materials and integrating ATMS (according to the strategy applied) can reduce the indoor temperature up to 5.2 °C, decrease the annual overheating hours up to 59.85%, and enhance the occupants’ thermal comfort, however, they are having moderate to high initial cost. According to the results, ATMs can reduce the energy consumption for cooling up to 48.7%, compared with conventional air conditioning systems, and therefore they can decrease monthly running costs. All results are fed into an excel based tool, created by the author, to create an easy to use program namely “ATM-Building” which can be used by architects in the early stages of design concept in order to easily compare each system performance into new buildings from the design stage and select the most appropriate ATM system.