Wyniki wyszukiwania - BazTech

1

Lengthwise finning surface as the method of influence on the flow separation in diffusers

Zaryankin A., Rogalev A., Lisin E., Khudyakova V.

Journal of Applied Mathematics and Computational Mechanics

|

2017

|

Vol. 16, nr 1

127--138

EN

The paper deals with the analysis of power factors acting within the boundary layer for different types of flow: convergent, gradientless and diffuser. Based on the considered formation mechanism of boundary layer separation, a hypothesis about the possible influence on structure and character of a separated flow by changing the gradient of the tangential stresses in the boundary layer was proposed. This impact is proposed to realize by means of the longitudinal finning of diffuser. Verification of the concept is performed on the basis of numerical flow investigation and available experimental data.

2

Niekonwencjonalna metoda tworzenia transferu wartości wzorca przepływu gazu ziemnego

Seredyuk O. E., Kruk I. S., Malisevich V. V., Warszawa Z. L.

Gaz, Woda i Technika Sanitarna

|

2013

|

Nr 1

7--11

PL

Przedstawiono podstawy teoretyczne udoskonalonej metody przekazywania wartości wzorca przepływu gazu i dla pomiarów przepływu gazu ziemnego zaproponowano realizację techniczną transferu z wykorzystaniem przepływomierzy o zmiennym spadku ciśnienia. Rozpatrzono możliwości przekazywania wartości miary wzorca od etalonu krajowego, lub wtórnego wzorca odniesienia w państwowym systemie kontroli przyrządów pomiarowych, do gazomierzy użytkowych z uwzględnieniem rodzaju medium roboczego i zmian jego parametrów. Przeprowadzano aprobatę działania modelu takiego transferu przy pomiarach przepływu powietrza z zastosowaniem zwężki Lavala i dzwonowego stanowiska kalibracyjnego do wytworzenia wzorca roboczego.

EN

The methodological study and technical solution for creation the transmission of standard values of consumption of natural gas using ѵагіаblе differential pressure flow meters were proposed and justified. The possibility of transferring of the standard gas flow rate values for natural gas consumption measurements taken from the State standard (etalon) or from the second level reference standard in the State verification system with taking to consideration changes of gas parameters and type of working medium (air or natural gas) were conducted. The experimental verification of the designed transfer unit model based on Laval type nozzle and the bell calibration stand to create the working standard was held.

3

Comparison of experimental data and numerical simulation of two-phase flow pattern in vertical minichannel

Sowiński J., Krawczyk M., Dziubiński M.

Chemical and Process Engineering

|

2012

|

Vol. 33, nr 1

63-70

EN

The aim of the study was the implementation of a numerical simulation of the air-water two-phase flow in the minichannel and comparing results obtained with the values obtained experimentally. To perform the numerical simulations commercial software ANSYS FLUENT 12 was used. The first step of the study was to reproduce the actual research installation as a three-dimensional model with appropriate and possible simplifications - future computational domain. The next step was discretisation of the computational domain and determination of the types of boundary conditions. ANSYS FLUENT 12 has three built-in basic models with which a two-phase flow can be described. However, in this work Volume-of-Fluid (VOF) model was selected as it meets the established requirements of research. Preliminary calculations were performed for a simplified geometry. The calculations were later verified whether or not the simplifications of geometry were chosen correctly and if they affected the calculation. The next stage was validation of the chosen model. After positive verification, a series of calculations was performed, in which the boundary conditions were the same as the starting conditions in laboratory experiments. A satisfactory description of the experimental data accuracy was attained.