Introduction. The article presents the results of calculating the energy efficiency of windows using a sun protection structure (SZK) of the rectangle type for buildings facing the southeast direction in the climatic conditions of the cities of Hanoi and Moscow, using the new proposed method described in Evaluation of the energy efficiency of a window system with a П-type sunshade. In the conditions of Vietnam, for buildings with a southeast orientation (southwest orientation), the use of a rectangular SZK is considered the most appropriate.
Materials and methods. the calculations are based on the projection of the sunbeam when calculating a part of the window area in the shade, considering the coefficient of reducing the irradiance of diffuse solar radiation by a shading device. In the presence of the shading device, there is a reduction in the intensity of diffuse solar radiation, which is represented by the coefficient Kbt. This coefficient was determined by experiments and proposed by regression equations. A computer program for calculating SZK was created to facilitate evaluation and design practice.
Results. The article analyzes the effectiveness of rectangular sun protection divice, compared with a egg-crate shaped structure. Solar heat gain q through the southeastern window was calculated for the two types of SZK mentioned above with solar radiation data from Hanoi and Moscow.
Conclusions. The results of the study show that the energy efficiency of the egg-crate shaped SZK is marginally better than the rectangle-type SZK for both cities. Rectangle-type SZK prove to be a good solution for building windows oriented to the east and south-east directions due to their simplicity.
