Passive Solar

PASSIVE SOLAR INTRODUCTION Passive solar is a “GREEN BUILDING “technique, which depends on natural convection process rather than mechanical transmitting source, which captures the heat energy of sun and delivers it during winter and pumps out the heat in summer, using heat distribution methods. Some of the heat distribution methods are Convection, Conduction, and Radiation. However components of passive solar heating are, the aperture area of the house, absorber area of the house, thermal mass of the house, heat distribution, and solar control. When these components work together it contributes to an efficient green building. In passive solar technique, glazing plays a vital role in absorption, transmission and distribution of solar radiations, moreover placing large windows in south side it increases the absorption of solar radiation, which will be essential during winter. The radiation getting in through the glazing is absorbed by concrete or masonry walls, stone floor slabs etc. These materials help in increasing absorption, density and have high specific heat capacity. This high energy heat is stored or retained by thermal mass of the material, which therefore transmits the heat absorbed when needed. There are four types of passive solar technique: suntempered, direct gain, indirect gain and isolated gain. Direct gain technique is very popular in residential applications, sun-tempered is used to provide valuable amenity to homes and thermal storage walls are used to support night-time heating. Passive solar heating method is adopted in cold zones for keeping the building to be warm and cold when needed by natural process. The supremacy of this method are, less installation cost, maintenance cost, no greenhouse gas emission and the most desirable feature is that, it almost reduces 50% of house heating bills. MODEL DESCRIPTION The model selected for the analysis is “Base case model of two offices and a passageway action”. The model comprises of three zones they are manager-A, manager-B and corridor. The manager-A and manager-B are adjacent to each other with separate entrance. Bilaterally offices have an expanse of one occupant during office hours, one computer in the room and lighting at 10W/m2. The office- A and B comprises, door of area: 2.320m2, base or floor surface area: 13.5m2 and total volume of an office is 40.5m3. Adjacent to the door, a partial glazing frame of surface area: 4.480m2 is provided in corridor zone. Between the head of a double glazing window a spandrel is provided, which is an insulated frame and this glazing helps to increase the absorptivity of sunlight, in the same degree- the double glazed frame of left and right door in the Corridor zone have the above susceptibility. An annual climate location is changed to Birmingham, whose site location is 52.5N, 1.7W of local meridian, simulation year is 1995 and its ground reflectivity constant is 0.20. Subsequently simulation is carried out for the winter climate, in which the solar radiation absorbed by the each office is 1311.1 W. Furthermore in the summer season, energy absorbed by an individual office is 1389.3 W. Beside coordinate vertices 16 and 17 of the window in office-A is modified. Ensuing, an area of the window is reduced. As an effect solar diffusion consumed by the office-A will get reduced for the above two seasons, whereas an office-B remains the same. The above analysis is carried out in the presence of the control used in the zone. In the dual office an Ideal control is used to control the zone functions. The sensor and actuator are used in this model, which senses

and activates the temperature and the air point of the up-to-date zone. The function day types are Weekdays, Saturdays & Sundays. Sensor function table DAY YEAR NUMBER OF PERIOD 1 Yes Yes Yes 2 Yes Yes No 3 Yes Yes No HEATING SET POINT IN PERIOD 1 2 3 15 19 15 15 19 Free floating 10 COOLING SET POINT IN PERIOD 1 2 3 26 24 26 25 16 Free floating 30 -

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