Transmission Heat Exchange of Buildings on Soil Foundations in Indoor Microclimate in Real External Meteorological Conditions

One of the tasks in the construction and operation of residential and public buildings is to meet the requirements for indoor microclimate. Current thermal microclimate depends on the building heat exchange with the external environment and on the climate control equipment. At the same time, the heat exchange with the external environment depends on constantly changing external conditions: air temperature, direct and diffuse solar radiation, radiant heat exchange with surrounding objects, and non-stationary heat transfer through ground foundations. All this must be taken into account by engineering climate systems in order to ensure rooms with the appropriate microclimate. Purpose : The purpose of the work is to compare annual heat losses of a building through enclosing structures of rooms, both in and not in contact with ground foundations, determine the contribution of heat loss through soil foundations to overall heat losses through opaque enclosing structures. Methodology : The studies include computational experiments to determine an unsteady indoor heat transfer quantities in the surrounding environment. The unsteady heat transfer boundary problem is expressed in parametric form and contains variable similarity criteria. Research findings : Indoor studies are conducted at various parameters, using archival meteorological data for Moscow, 2011. The heat exchange with the soil foundation influence on the overall transient heat exchange is determined for different seasons and different orientations inside the building relative to cardinal directions. It is shown that indoor contact with the soil foundation leads to an increase in the average heat loss over seasons, regardless of the cardinal orientation and parameters of enclosing structures. The minimal increase in relative heat loss (no more than 18 %) occurs in winter. The maximum impact of the contact between rooms and soil foundation occurs in summer. Heat loss increases up to fourfold compared to rooms not in contact with the soil and, depending on the type of the enclosing structure, it can be two times higher on the southern façade than on the northern one. For rooms in contact with soil foundations, the average seasonal amplitudes of daily changes in the heat loss are reduced for all types of enclosing structures.