Andrzej Flaga

The paper presents tests of wind velocity distribution at the inlet to the working section of a wind tunnel.
Unconventional guide vanes were introduced in the construction of the wind tunnel to obtain a uniform
air flow in this area.

This paper presents an acoustic study of the auditorium hall located in the proposed building of the Applied Acoustics Laboratory of Cracow University of Technology. The study shows a comparative analysis of two solutions to the acoustic adaptation of this room. The aim of this study was to demonstrate that with a given room shape and finishing materials, it is possible to optimize the sound quality of the interior through changes to some architectural details, for example, by the adequate formation and arrangement of finishing elements.

This paper summarizes results of wind tunnel tests of a high-rise building placed in Warsaw city centre. Aerodynamic laboratory studies were accomplished in a boundary layer wind tunnel. The main objective of the research was to determine the distribution of the mean wind pressure coefficient over the building’s external surfaces as affected by the aerodynamic interference between the structure and its immediate city surroundings. Interference coefficients of wind pressure and global wind forces acting upon the surfaces of the building walls and roof were calculated. The aerodynamic studies showed a significant influence of objects located nearby on the wind load that the high-rise building structure surfaces are subjected to.

The paper concerns dimensional analysis and the theory of model similarity of physical phenomena. At the beginning of the considerations, basic notions, definitions, relationships and fundamental principles of the issues to be analysed has been presented. Next, Buckingham’s Π-theorem of dimensional analysis and theory of similarity as well as authorial generalized theorems Π of this field of interest have been derived. A separate chapter has been devoted to the problem of the nature of physical phenomena occurring in the mechanics of continuous or discrete material mediums. At the end of the paper, an example of the determination of similarity numbers in the case of a system with one degree of freedom at mechanical and kinematic excitation have been given.

This paper describes model tests conducted in the Wind Engineering Laboratory of Cracow University of Technology on dynamic action on the atmospheric boundary layer in order to reduce the effects of air pollution and smog in urban areas. The paper focuses on vertical exhaust (ventilation chimney) and cooperation between a concentric system of ventilation towers and a ventilation chimney. The tests were conducted for different shapes and heights of ventilation chimneys, different diameters of the concentric system and different wind speeds provided by the ventilation towers. A heavy smoke visualisation was performed in order to qualitatively evaluate the efficiency of different solutions. The performed tests confirmed a sufficient level of efficiency of cleaning an area where the circular system is located.

Keywords: wind engineering, smog reduction, environmental engineering, urban ventilation, ventilation chimney, smoke visualisation

Streszczenie

Artykuł opisuje badania modelowe przeprowadzone w Laboratorium Inżynierii Wiatrowej Politechniki Krakowskiej dotyczące dynamicznego oddziaływania na warstwę przyziemną atmosfery w celu redukcji zanieczyszczenia powietrza i smogu w obszarach zurbanizowanych. Praca skupia się na pionowym wylocie powietrza (kominie wentylacyjnym) i współpracy pomiędzy koncentrycznym systemem wież wentylacyjnych i tym kominem. Pomiary zostały przeprowadzone dla różnych kształtów i  wysokości komina, różnych średnic pierścienia wież wentylacyjnych i różnych prędkości powietrza podawanych przez wentylatory. Wykonano wizualizację dymową dla określenia jakościowego wydajności różnych rozwiązań. Badania potwierdziły wystarczającą wydajność systemu do wyczyszczenia obszaru, w którym się znajduje.

Słowa kluczowe: inżynieria wiatrowa, redukcja smogu, inżynieria środowiska, przewietrzanie miast, komin wentylacyjny, wizualizacja dymowa 

This paper describes model tests conducted at the Wind Engineering Laboratory of Cracow University of Technology as the first stage of studies on dynamic action on the atmospheric boundary layer in order to reduce the effects of air pollution and smog. It focuses on the cooperation between a series of ventilation towers placed one by one (or row by row) in order to generate a continuous airstream with sufficient velocity to aid the natural ventilation of urban areas. The tests were conducted for three different terrain categories with varying roughness. Also tested were different wind speeds, different spacing between the towers and different configurations of the towers in each row. As a preliminary set of tests, this enabled verification of the feasibility of the solution and its effectiveness on a rough terrain that simulates urban areas.

Keywords: wind engineering, smog reduction, environmental engineering, urban ventilation, terrain roughness

Badania modelowe dynamicznego oddziaływania na warstwę przyziemną atmosfery – konfiguracja liniowa wież wentylacyjnych na chropowatym terenie 

Niniejszy artykuł opisuje badania modelowe przeprowadzone w Laboratorium Inżynierii Wiatrowej Politechniki Krakowskiej w ramach pierwszego etapu studium dynamicznego oddziaływania na warstwę przyziemną atmosfery w celu redukcji zanieczyszczenia powietrza i smogu. Praca skupia się na współpracy kilku wież wentylacyjnych ustawionych jedna za drugą (lub rząd za rzędem) w celu utworzenia ciągłej strugi powietrza o dostatecznej prędkości, by wspomóc naturalną wentylację obszarów zurbanizowanych. Badania przeprowadzono dla trzech różnych kategorii chropowatości terenu. Ponadto sprawdzono wpływ różnych prędkości strugi, różnych odległości pomiędzy wieżami i różnych wzajemnych konfiguracji wież w każdym rzędzie. Przeprowadzone badania wstępne pozwoliły na weryfikację wykonalności tego rozwiązania oraz jego wydajności na chropowatym terenie odpowiadającym obszarom zurbanizowanym.

Słowa kluczowe: inżynieria wiatrowa, redukcja smogu, inżynieria środowiska, przewietrzanie miast, chropowatość terenu

The paper presents results of wind tunnel experiments of wind action on two free-standing lighting protection masts: cantilevered and tripod. Own similarity criteria concerning phenomenon of global stability loss were used in these tests. It was determined whether masts fulfill the requirements of overturning and shift global stability in range of base wind velocities adequate for Poland and different categories of terrain roughness according to the Eurocode [13]. Two possible forms of the loss of the global stability of lighting protection masts in strong wind were considered: overturning a mast and shifting of mast as a whole structures. The measurements were conducted for eight directions of wind attack, five positions of masts on the roof, two settings of the mast for tripod mast and one for cantilevered mast, two categories of terrain roughness. Conducted tests allowed to determine whether it is safe to locate tripod mast in all wind zones in Poland. Cantilevered mast can be located safely in I and II wind zone in Poland.

The paper summarizes the wind tunnel tests of original acoustic panels located on the block buildings roofs near edge of building roof and walls. Performed investigations had two main goals: 1. Verification of resistance of the panels at their connecting members at high air flow velocities; 2. Determination the set of aerodynamic force coefficients, obtained from measured wind pressure distribution on the façade panel surfaces in two opposite wind directions, was the main aim of the work.

In the paper, wind tunnel tests of wind action on an aquaporine model exhibit performed in a boundary layer wind tunnel of the Wind Engineery Laboratury at the Cracow University of Technology have been presented. In the experiments, most of the similarity criteria elaborated specially for this purpose have been fulfilled. Moreover, safety assessments of the exhibit with respect to a strong wind action have been done.

The paper presents a set of wind tunnel tests performed for four box-shape solids. The tests were performed in a wind tunnel with a modelled boundary layer. The main objective of the research was to determine the mean wind velocity and turbulence at selected points. Potential placement of wind turbines is considered for those points. The paper includes a description of measurement, tests results and analysis of the results. Conclusions contain determination of necessary conditions for the best setup.

This paper deals with the derivation of similarity criteria for the phenomenon of railway wagons rolling over when exposed to strong crosswinds. Utilizing these criteria, the authorial method for the determination of the aerodynamic coefficient of the rollover moment is also presented in the paper.