Goncharuk S. Heat transfer features in the administrative building with convector heating system.

The objects of research are three-storeyed frame panel administrative building, which was built in 1973, and its typical rooms with convector heating system. The subject of the research is the process of heat transfer and aerodynamics air as indoors, as by the interaction with environment. The purpose of work is to find out the features of heat transfer and to make a number of theoretical and experimental researches of air-temperature conditions in the main living room and the building as a whole; to determine the heat loss through the enveloped building and to develop the methods of itself decline by rational use of heat modernization knowledge. Methods of research - analytical, experimental, numerical thermo physical modeling, and energy audit of the building. General results of work: a) thermal imaging and heat metrical research of walling administrative building and analyzing its thermo condition were held, areas with the highest level of heat loss identified, experimentally discovered a new thermo physical effect consisting in turning the direction of heat flow on the outer northern surface of three-layer sandwich-panels, connected with structure feature of the outer panel, with non-stationary processes of heat transfer and with the influence of the daily diffuse solar radiation; b) as the result of three-dimensional modeling were obtained new data of allocation of temperature and hydrodynamic characteristics of the internal air flow in the individual rooms in a building heating system convector, theoretically established the presence of circulating bands in the area near the premises of the convector, and near the floor with average speed up to 0.1 m / s; in central area in the direction of the two-pane convector vertically installed locally increasing circulation rate and air temperature in the room at a height of 25 cm from the floor up to 0.07 m / s and 17 ° C (average room temperature - 20 ° C ) and at a height of 240 cm - 0.1 m / s; c) for the numerical analysis of velocity field, pressure and temperature near the surface of the building was created thermo physical model of turbulent transport of momentum and energy of wind flow, which it washes, was shown the influence of velocity and direction of wind flow on the characteristics of the distribution of local heat transfer coefficients on the surfaces of the building and was found that - more than 100 W /(sqr.moK) they acquire at the junction end faces of the building with its side surfaces and a roof, which is necessary to heat modernize; d) was developed a new numerical thermo physical model of heat transfer inside the office building, which allows to find the characteristics of the temperature distribution in the building depending on the location of premises in the overall volume and determine the heat loss through the enveloped building due to heat transfer from the surface of fences and infiltration; e) was developed a numerical thermo physical model of radiation-convection heat transfer from two-panel convector and were found the radiative and convective components of the heat flux from the surface at a surface temperature of 45 to 85 ° C, it was theoretically found that the radiative heat flux from the surface is two-panel convector about 30% of the total heat flux; g) the method of thermo physical modeling regularities of radiation-convective component of the heat flux passing through the single and double glazing, theoretically established that the radiative heat flux up to 70% in the single and up to 65% in the triple-pane windows; h) was designed and created experimental stand for research heat insulating ability heat modernize area external cladding (with additional insulation basalt wool with reinforced plaster ball) building in terms of its actual operation; a) propose specific low-cost and capital measures to reduce heat administrative buildings, which selected the object of research. Results have been implemented: (a) in terms of the methodology for determining the heat loss through the enveloped building in a specialized school in the survey thermal insulation capacity of the exterior wall and translucent structures (school №118 "Vsesvit", Kiev); (b) on PrJSC "Energymountingventilation" to calculate the distribution of air velocity and temperature inside the heated building, which is confirmed by the relevant acts.