The paper deals with ionization impact on efficient cleaning of air in a measuring chamber which has been cleaned and closed against any outer impacts (e.g. impurities, dust from another room, human odours). Smoking has an impact on the number of positive and negative ions including the concentration of particulate matter PM 10 . We investigated the ion concentration according to the presence of cigarette smoke in the room and according to the change of lit cigarette distance from the supply of ionized air. Due to the experiment there was simulated smoking at the relative air humidity φ = 37 % and φ = 39 % and temperature of 20 °C in the room. Increased PM 10 concentrations were caused only by cigarette smoke pollution or more precisely by artificially created higher humidity in the measuring room excluding ambient environment impacts. The aim of the experiments was to prove influence of ionization on the elimination of cigarette smoke. The measurements showed that the highest efficiency of PM 10 particulate removal was achieved when the distance of smoking cigarettes from ionization source was 3 m and the air humidity was 39 %. The consequent increase of the distance of smoking cigarettes from the ionization source significantly decreased the efficiency of particle removal. The difference between ionized and natural air is minimal at the bigger distance.

-The paper shows the analysis of the effect of introduction of an exit tube into the cylindrical part of a cyclone on the flow velocity, pressure losses and, above all, the separation efficiency. We made measurements and carried out CFD simulations for three levels of the exit tube introduction. The ratios of the depth of the exit tube introduction to the cyclone diameter (Hp/D) were 0.4, 0.475 and 0.89 at three velocity settings of 8 m.s -1 , 13 m.s -1 and 15 m.s -1 . The Reynolds Stress Model (RSM), which was compatible with the experimental results, was used for numerical solutions. The efficiency of cyclone separation was explored on a sample of oak sawdust. The efficiency of cyclone separation increased with the geometric size of the particles, the inlet velocity and a deeper introduction of the exit tube.

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The contribution deals with the comparison of possibilities of utilizing two experimental methods: digital and classical holographic interferometry for the visualization of beam motion. The girders are used in civil and mechanical engineering and considering the technical point of view it is necessary to learn to what extent the beam is deformed at the load and how much it can withstand.

The paper deals with the visualization of temperature fields in the vicinity of profiled heat transfer surfaces and a subsequent analysis of local values of Nusselt numbers by forced air convection in an experimental channel. Holographic interferometry was used for visualizing the temperature fields. Experiments were carried out at Re 462 up to 2338 at the distances between heat transfer surfaces of 0.025 m and 0.035 m. Temperature contours were determined from the obtained images of holographic interferograms of temperature fields and the local values of Nusselt numbers along the profiled surface for x/s = 0 up to x/s = 1.25 were calculated from them. A significant effect of the profiled surface on the local values of Nusselt numbers can be observed from the obtained results.