Designing Thermal Mass in Naturally Ventilated Buildings

According to its location, thermal mass can be approximately classified into two types: external and internal. Internal thermal mass, such as furniture and purpose-built internal concrete partitions, does not expose to ambient temperature directly, while external thermal mass, such as walls and roofs, expose directly to ambient temperature variation. A virtual sphere method for modelling thermal mass is introduced and its application in building thermal mass design is discussed.

LOW-ENERGY COOLING FOR IMPROVED THERMAL COMFORT IN OFFICES

This study has explored the possibility and potential of using a thermal active mass system for reducingthe temperature rise and increasing the thermal comfort in an office room. The Controlled Active Mass(CAM) will be used as a heat sink to absorb heat from the room in order to increase the thermal comfort.Physically, the CAM system was designed as a cubic-shaped tank filled with water, with the tanksurfaces either polished or black.

Case Study : Temperature evolution and thermal mass in a passively ventilated office : Houghton Hall, England

We report on a series of measurements of the temperature at Houghton Hall, Luton,over the Spring and Summer of 2003. The data show that the building tracks the externaltemperature, but that the amplitude of diurnal temperature fluctuations typically lies within 2-6 C,while the external fluctuations may be as large as 15-25 C. This buffering of the internaltemperature is largely due to the thermal mass of the space which introduces a time-lag ofbetween 0.5-3.0 hours in the response time of the interior to the exterior space, over the periodof our survey.

Numerical Study of Thermal Response of School Buildings in Winter Conditions

In this work a numerical model, that simulates the buildings thermal response and evaluates theinternal air quality in transient conditions, is validated and used. This multi-nodal model calculates notonly the buildings temperatures and the air water vapour and contaminants mass, but also the air relative humidity inside the spaces, the solar radiation inside and outside building surfaces, the heat and mass convection coefficient, the views factors between internal surfaces, the heat and mass fluxes and the global thermal comfort level.

Simple Modelling of Thermal Mass

In this study, the effect of the thermal mass and thermal insulation of a ventilated building onthe indoor environment is investigated. A simplified model of the thermal interaction between a building structure and the interior is developed. Three important parameters are determined, and analytic expressions for the attenuation and phase lag of harmonic external forcing are derived for an unventilated interior. The effect of forced or stack-driven natural ventilation on the interior response is then investigated.

Glass partitions, ventilation and thermal mass as retrofitting measures in an attached sunspace

In this paper the effectiveness of retrofitting strategies in a sunspace attached to a one-storey building has been investigated. Natural and hybrid ventilation, air-tight glass partitions, awnings and increased thermal mass retrofitting scenarios were implemented, mainly for the Greek climate. Window openings and sensor-controlled fans were used to create a controllable and secure environment. Combined ventilation and thermal simulation were applied, taking into account all the related physical phenomena, such as ventilation, infiltration and solar radiation.

Predicting indoor temperatures in closed buildings with high thermal mass

Temperatures in buildings with low and high thermal mass levels have been monitored during the warm period in Kenya. The effect of thermal mass in lowering the maximum indoor daytime temperatures has been evaluated as very effective.

Effect of thermal mass on natural ventilation in a single-zone building with two openings

This paper considers an ideal naturally ventilated building model that allows a theoretical study of the effect of thermal mass associating with the non-linear coupling between the airflow rate and the indoor air temperature.The thermal mass number and the convective heat transfer air change parameter are suggested to account for the effect of thermal mass heat storage and convective heat transfer at the thermal mass surfaces. The new thermal mass number measures the capacity of heat storage, rather than the amount of thermal mass.

An energy conscious house for Malta

Winner of First Prize in the 2 nd Commonwealth Inter-school Design Competition organised by theCommonwealth Association of Architects (CAA), 1991. The winning design was a pair of houses with wind towers. It was praised by the jury as an innovative and original solution to the brief recognising local conditions, elegantly and thoughtfully presented. The planning of the dwelling pleasantly reflected the local lifestyle with an interesting internal environment.

Nightsky natural cooling system saves energy.

Nightsky, an innovative night roof spray storage cooling system, provides chilled water to in-slab tubing and fan coils. Passive cooling delivery from the slab cools the building in parallel with the 'active' chilled-water fan coils. Delivering a significant fraction of the building's cooling requirements via the floor slab allows that size of the forced-air delivery system to be reduced. NightSky is most appropriate for large, low-rise buildings that have low-slope roof areas.

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