*5.1. Assumptions and Output Parameters*

Using the previously given equations, calculations of the parameters of the room and the external partition were made for variable external conditions [41].

The calculations were made for several variants of rooms with general assumptions:


Data for calculations, with values (according to [43]):

qA = 6.8 W/m2—single-family buildings, qA = 7.0 W/m2—multi-family buildings, VVe <sup>=</sup> 0.31 <sup>×</sup> <sup>10</sup>−<sup>3</sup> <sup>m</sup>3/(s' m2)—single-family buildings, VVe <sup>=</sup> 0.32 <sup>×</sup> <sup>10</sup>−<sup>3</sup> <sup>m</sup>3/(s' m2)—multi-family buildings.

Relationship between VVe coefficient and the number of exchanges n:

$$\mathbf{n} = \frac{\mathbf{3}.6 \cdot \mathbf{V\_{We}}}{\mathbf{h}} \tag{27}$$

h—room height.

Thermal conductivity:

λ<sup>1</sup> = 0.82 W/mK (brick wall),

λ<sup>2</sup> = 0.032 W/mK (polystyrene insulation).

Room dimensions:

a = 3.0 m—the width of the room,

b = 4.0 m—room depth,

h = 3.0 m—room height,

Ao = 1.96 m2—window area.

Meteorological data:

Sample calculations were made using the meteorological data for the Rzeszów-Jasionka measuring station.

The table of hourly changes in outside temperature and changes in the intensity of solar radiation was used, provided by the website of the Ministry of Infrastructure [40].

The example assumes the location of the outer wall towards the north.

It is assumed that the final result of the calculations will be the determination of the variability of the heat demand for space heating over the year, taking into account the variability of climatic conditions and the inertia of building partitions.

The basis for determining the heat demand is Equation (2). The components of the equation were determined by Equations (3)–(10) using the assumptions made above.

The calculations were made for a living room with an external wall made of brick, 50-cm thick, for the cases: without insulation and with insulation with a layer of polystyrene 5-, 10-, 15-, 20-, and 25-cm thick. The results of the calculations are presented in the following charts.
