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- HEAT SUPPLY, VENTILATION, AIR CONDITIONING, LIGHTING
- Effect of Side Walls on the Character of Air Three-Dimensional Turbulent Flow in the Room
- UDC 628.83

**Vladimir N. VARAPAEV**, e-mail: varapaevvn@mgsu.ru

**Nerses S. SIMONYAN**, e-mail: n.s.simonyan@gmail.com

Moscow State University of Civil Engineering (National Research University), Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation

**Abstract**. This article presents the results of numerical simulation of airflows in a ventilated room with ANSYS CFX. In particular, it considers the three-dimensional isothermal case with the use of , , SST è BSL models; an evaluation of the character of three-dimensionality in the flow considered was made. The formulation of the problem fully corresponds to the selected experimental model for which the measurements of air flow, velocity profiles and pulsation energy of turbulence were made in the aerodynamic laboratory of MGSU using PIV-technology. For an evaluation of the non-stationarity presence in the airflow considered, the calculations were made both for stationary and non-stationary models. It is shown that in the case of the model in the middle part of the area two-dimensional and three-dimensional calculations give approximately the same results for both stationary and non-stationary case. When using the model, the symmetric flow is observed only in case of the use of non-stationary model and with a stationary model, the flow can be asymmetric with respect to the average cross-section character. Tasks of this type are necessary for the analysis and calculation of ventilation and air conditioning systems of buildings for various purposes.

**Key words**: numerical simulation, three dimensional flow, turbulence model, ANSYS CFX, ventilated room, stationary and non-stationary calculations. - REFERENCES

1. Varapaev V. N. Mathematical modeling of combined heat transfer under natural air convection in open areas. Vestnik MGSU, 2010, no. 1, pp. 248-254. (In Russian).

2. Varapaev V. N., Kitajceva E. H. Matematicheskoe modelirovanie zadach vnutrennej aerodinamiki i teploobmena zdanij [Mathematical modeling of problems of internal aerodynamics and heat transfer of buildings]. Moscow, SGA Publ., 2008. 338 p. (In Russian).

3. Nielsen P. V., Restivo A., Whitelow J. H. The Velocity Characteristics of Ventilated Rooms [Õàðàêòåðèñòèêè ñêîðîñòè â âåíòèëèðóåìûõ ïîìåùåíèÿõ]. Journal of Fluids Engineering, September 1978, vol. 100, pp. 291-298. DOI: 10.1115/1.3448669.

4. Nielsen P. V. Specification of a two-dimensional test case [Îïèñàíèå ñëó÷àÿ äâóõìåðíîãî òåñòà]. Department of Building Technology and Structure Engineering. Aalborg University, November 1990, pp. 1-15.

5. Li Rong, Nielsen P. V. Simulation with different turbulence models in an annex 20 room benchmark test using Ansys CFX 11.0 [Ìîäåëèðîâàíèå òåñòîâîé çàäà÷è äëÿ ïîìåùåíèÿ àííåêñ 20 äëÿ ðàçëè÷íûõ òóðáóëåíòíûõ ìîäåëåé ñ èñïîëüçîâàíèåì âû÷èñëèòåëüíîãî êîìïëåêñà Ansys CFX 11.0]. DCE Technical Report, Aalborg University, 2008, no. 46, pp. 1-12.

6. Varapaev V. N., Doroshenko S. A., Kapustin S. A., Orekhov G. V., Churin P. S. Creation of an experimental stand for model studies of internal aerodynamics of premises by the method of digital tracer visualization. Vestnik MGSU, 2012, no. 12, pp. 117-124. (In Russian).

7. Varapaev V. N., Doroshenko S. A., Kapustin S. A., Trocko A. Yu. Experimental and numerical simulation of three-dimensional turbulent flows in a ventilated room. International Journal for Computational Civil and Structural Engineering, 2015, vol. 11, iss. 2, pp. 79-88. (In Russian).

8. Pedersen J. M., Meyer K. E. POD analysis of flow structuresin a scale model of a ventilated room [Àíàëèç ñîáñòâåííûõ îðòîãîíàëüíûõ ðàçëîæåíèé ñòðóêòóðû ïîòîêà â âåíòèëèðóåìîì ïîìåùåíèè]. Experiments in Fluids, 2002, vol. 33, iss. 6, pp. 940-949. DOI: 10.1007/s00348-002-0514-8.

9. Nielsen P. V., Li Rong, Olmedo I. The IEA Annex 20 Two-Dimensional Benchmark Test for CFD Predictions [Ðåøåíèå òåñòîâîé çàäà÷è Àííåêñ 20 â äâóõìåðíîì ñëó÷àå ìåòîäîì êîìïüþòåðíîãî ìîäåëèðîâàíèÿ]. Clima 2010, 10th Rehva World Congress. Turkey, 2010, ðp. 81-84.

10. Olmedo I., Nielsen P. V. Analysis of the IEA 2d test. 2d, 3d, steady or unsteady airflow? [Àíàëèç äâóõìåðíîãî òåñòà. Âîçäóøíûé ïîòîê ÿâëÿåòñÿ äâóõìåðíûì èëè òðåõìåðíûì, ñòàöèîíàðíûì èëè íåñòàöèîíàðíûì?]. Technical report. The University of Aalborg, Department of Building Technology and Structural Engineering, 2010, pp. 1-7. **For citation**: Varapaev V. N., Simonyan N. S. Effect of Side Walls on the Character of Air Three-Dimensional Turbulent Flow in the Room.*Promyshlennoe i grazhdanskoe stroitel'stvo*[Industrial and Civil Engineering], 2018, no. 12, pp. 55-59. (In Russian).

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