Marek Ochowiak received a Ph.D. degree in chemical technology from Poznan University of Technology. Since 2002 works in Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology. Obtained Dr. Eng. Habil. degree in chemical engineering from Silesian University of Technology (2014). Since 2016 he is the head of Department of Chemical Engineering and Equipment. Associate Professor Ochowiak’s research interests include chemical and process engineering, mechanics, automatics, esspecially: multiphase systems, atomization process, separation processes, and computer analysis of images. He has published more than 28 papers in JCR journals. His hobbies are photography, reading and travel

The aim of this work was to analyze the effect of aeration on distribution of drop sizes in the aerosol. The aerosol was generated with a pneumatic medical nebulizer fitted with a modified nebulizer cup connected to the additional source of aerating gas. The size of drops formed was analyzed with a digital microphotography with prior capture of drops onto the immersive liquid layer. The photos obtained were analyzed in Image-Pro Plus. The mean drop diameter and volumetric share of drops of 5 µm and 10 µm were analyzed. Based on results, the effect of aeration of liquid on the dispersion process was evaluated. Modification of the nebulizer cup consists in making four holes in the bottom of this vessel . All tubes (used as the aerator) coming out from the holes were connected to the collector to which an additional air stream from another Medel Family pneumatic nebulizer was provided via a hose by rotameter and valve. The valve enables control of the flow rate of additional air fed to the nebulization cup. Dispersion Atomization in pneumatic medical nebulizer with different gas flow rates by dispersed liquid was tested. The tests were conducted within the flow rate of additional gas from 1.39•10-5 to 8.33•10-5 m3/s. The work also analyzed the size of bubbles flowing out from a single aerator orifice with a flow rate of additional gas from 6.44•10-6 to 8.33•10-5 m3/s. The analysis of drops size histograms shows that with the higher flow rate of gas, the number of large drops decreases and there are more smaller drops. With the higher gas flow rate, the drops size distribution curve clearly moves towards the smaller drops. Based on these tests it was found that: when the gas flow rate is higher, there are more smaller drops, there are less drops with large diameters; the mean drop diameter decreases under higher flow rate of additional gas stream; the higher gas flow rate increases the volume of the bubble flowing out through a single opening, and it was further found that the design modifications of atomizing equipment could contribute to improving efficiency of aerosol therapy thanks to obtaining smaller diameters of drops.

Magdalena Matuszak was born in 1988. In 2016, she graduated from Poznan University of Technology, Faculty of Chemical Technology, Institute of Chemical Technology and Engineering and obtained Ph.D. degree. In October 2016 she started to work at Poznan University of Technology, Department of Chemical Engineering and Equipment as assistant. She research interests include chemical and process engineering, esspecially: multiphase systems, atomization process, and computer analysis of images. She carry out research, which are concerned with the analysis of the atomization process in medical devices. She has published more than 9 papers in JCR journals. Her hobbies are reading and travel.

Atomization of liquid is widely used in industry (including aerosol therapy, spray drying, powder and emulsion production and agrotechnical treatment). In the recent years, a high interest in aerosol therapy has been noted. This type of therapy has a series of advantages such as: an easy, convenient and quick drug administration, low invasiveness, ability to choose an individual type and dose of medication. It is worth to note that a higher interest in inhalation techniques may be due to the fact that nowadays, the respiratory diseases are one of the most frequent and fast developing in the world affecting whole population in a wide age range. In aerosol therapy and effective delivery of drugs to specific respiratory tract regions a key role is played by a size of drops. It is due to the fact that the drops with greatest diameters (> 5 µm) mostly deposit in the upper respiratory tract while drops with diameters of ≤ 5 µm deposit in the lower respiratory tract. The existing research often concerns the method of improving the efficiency of atomization process by affecting the diameters of drops and drops size distribution curves. As part of the research, an attempt was made to modify the pneumatic nebulizer in order to improve the atomization process as a result of smaller drops. For this purpose, the influence of the temperature of nebulized liquid with a use of additional aeration of liquid residing in a nebulizer cup, exerted on drops size histogram and size of drops were analyzed. The tests conducted showed that the proposed modification of the pneumatic nebulizer contributed to disappearance of drops with relatively large diameters, formation of more drops with smaller sizes and the distribution of drop sizes was more uniform.