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Particuology 2014年第4期12卷 129-137页

作者： Wojciech P.Adamczyk Adam Klimanek ryszard a.biaecki Gabriel Wecel Pawe Kozolub Tomasz Czakiert Institute of Thermal Technology Silesian University of Technology44-100 GliwiceKonarskiego 22Poland Institute of Advanced Energy Technologies Czestochowa University of TechnologyCzestochowaPoland

Particle transport phenomena in small-scale circulating fiuidized beds （CFB） can be simulated using the Euler-Euler, discrete element method, and Euler-Lagrange approaches. In this work, a hybrid Euler-Lagrange model known as the dense discrete phase model （DDPM）, which has common roots with the multiphase particle-in-cell model, was applied in simulating particle transport within a mid-sized experimental CFB facility. Implementation of the DDPM into the commercial ANSYS Fluent CFD package is relatively young in comparison with the granular Eulerian model. For that reason, validation of the DDPM approach against experimental data is still required and is addressed in this paper. Additional difficulties encountered in modeling fluidization processes are connected with long calculation times. To reduce times, the complete boiler models are simplified to include just the combustion chamber. Such simplifications introduce errors in the predicted solid distribution in the boiler. To investigate the conse- quences of model reduction, simulations were made using the simplified and complete pilot geometries and compared with experimental data. All simulations were performed using the ANSYSFLUENT 14.0 package. A set of user defined functions were used in the hybrid DDPM and Euler-Euler approaches to recirculate solid particles.

关键词： Particle Multiphase flow CFD Particulate processes CFB Fluidized bed

New Insight to the Surface Temperature of the Sun

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Energy and Power Engineering 2024年第8期16卷 285-292页

作者： ryszard Petela Professor Emeritus Calgary Canada

Information is given on thermal radiation from the Sun, considered in practical engineering calculations of heat exchange. It was found that although the surface temperature of the Sun is assumed to be about 5800 K, the solar spectrum data measured by Kondratyev lead to a value of at least 7134 K. Such a higher value can be obtained by interpreting the Planck formula for the black radiation spectrum for the Kondratyev data. In addition, using the Stefan-Boltzmann law, the energetic emissivity of the Sun’s surface was determined to be 0.431. Furthermore, based on Petela’s formulae for exergy of thermal radiation, the exergetic emissivity of the Sun’s surface was also calculated at the level of 0.426.

关键词： Thermal Radiation Radiation Temperature Surface Temperature Surface Emissivity Sun Radiation Spectrum Plank Law Exergy of Radiation Photosphere

Effects of the concentration and nature of total dissolved solids in drinking water on feed intake, nutrient digestion, energy balance,methane emission, ruminal fermentation, and blood constituents in different breeds of young goats and hair sheep

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Animal Nutrition 2024年第01期16卷 84-95页

作者： Amlan Kumar Patra Luana Paula dos Santos Ribeiro Hirut Yirga Adekayode O.Sonibare Ahmed R.Askar Ali H.Hussein ryszard Puchala Arthur Louis Goetsch American Institute for Goat Research Langston University Animal and Poultry Nutrition Department Desert Research Center Agriculture Food and Natural ResourcesEastern New Mexico University

Understanding how different livestock species and breeds respond to consumption of brackish water could improve usage of this ***,Angora,Boer,and Spanish goat doelings and Dorper,Katahdin,and *** ewe lambs (6 animals per animal type[AT];initial age=296±2.1 days)consuming water with varying concentrations of minerals of a natural brackish water source (BR) and sodium chloride (NaCl;SL) were used to determine effects on water and feed intake,nutrient digestion,heat energy,methane emission,ruminal fluid conditions,and blood constituent *** were 6 simultaneous 6 (water treatments[WT])×6 (AT) Latin squares with 3-wk *** WT were fresh (FR),BR alone (100-BR),a similar total dissolved solids (TDS) concentration as 100-BR via NaCl addition to FR (100-SL),BR with concentrations of all minerals increased by approximately 50%(150-BR),a similar TDS level as 150-BR by NaCl addition to FR (150-SL),and a similar 150 TDS level achieved by addition of a 1:1 mixture of BR minerals and NaCl to 100-BR (150-BR/SL).Concentrations (mg/kg) in BR were 4928 TDS,85.9 bicarbonate,224.9 calcium,1175 chloride,60.5 magnesium,4.59 potassium,1387sodium,1962 sulfate,and 8.3 boron,and TDS in other WT were 209,5684,7508,8309,and 7319 mg/kg for FR,100-SL,150-BR,150-SL,and 150-BR/SL,*** were very few significant effects of WT or AT×WT interactions,although AT had numerous *** intake was affected by AT (P=0.02)and WT (P=0.04),with greater water intake for 150-SL than for FR,100-BR,100-SL,and *** matter intake among AT was lowest (P<0.05) for *** of organic matter and neutral detergent fiber and heat energy differed among AT (P<0.05),but nitrogen digestion and ruminal methane emission were similar among *** aldosterone concentration was higher (P<0.05) for FR than for other *** conclusion,all AT seemed resilient to these WT regardless of mineral source and concentrations,with TDS less than 8300 mg/kg,which did

关键词： Goats Hair sheep Nutrient utilization Ruminal fermentation Salinity Water quality

Influence of Air-Jet Vortex Generator Diameter on Separation Region

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Journal of Thermal Science 2013年第4期22卷 294-303页

作者： ryszard Szwaba Institute of Fluid-Flow Machinery Polish Academy of Sciences (IMP PAN)

Control of shock wave and boundary layer interaction continues to attract a lot of attention. In recent decades several methods of interaction control have been investigated. The research has mostly concerned solid (vane type) vortex generators and transpiration methods of suction and blowing. This investigation concerns interaction control using air-jets to generate streamwise vortices. The effectiveness of air-jet vortex generators in controlling separation has been proved in a previous research. The present paper focuses on the influence of the vortex generator diameter on the separation region. It presents the results of experimental investigations and provides new guidelines for the design of air-jet vortex generators to obtain more effective separation control.

关键词： shock wave boundary layer separation control streamwise vortices air-jet vortex generator

Shock Wave Induced Separation Control By Streamwise Vortices

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Journal of Thermal Science 2005年第3期14卷 249-253页

作者： ryszard SZWABA Technical University of Liberec Faculty of Mechanical Engineering Division of Power Engineering. Halkova 6 461 17 Liberec Czech Republic

Control of shock wave and boundary layer interaction finds still a lot of attention. Methods of this interaction control have been especially investigated in recent decade. This research was mostly concerned with flows without separation. However, in many applications shock waves induce separation often leads to strong unsteady effects. In this context it is proposed to use streamwise vortices for the interaction control. The results of experimental investigations are presented here. The very promising results were obtained, meaning that the incipient separation was postponed and the separation size was reduced for the higher Mach numbers. The decrease of the RMS of average shock wave oscillation was also achieved.

关键词： streamwise vortices separation control boundary layer shock wave

Brain ischemia as a bridge to Alzheimer's disease

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Neural Regeneration Research 2022年第4期17卷 791-792页

作者： ryszard Pluta Laboratory of Ischemic and Neurodegenerative Brain Research Mossakowski Medical Research InstitutePolish Academy of SciencesWarsawPoland

An update of the etiology of Alzheimer's disease(AD):The current theory of the etiology of AD and the guidelines for most of the wide-ranging treatments activities are built around amyloid and tau protein as causative agents of the disease(Atlante et al.,2020).At present,based on a comprehensive evaluation of existing and contemporary studies,important questions arise regarding the causal role of amyloid and tau protein in the pathogenesis of AD(Morris et al.,2018).Analyzes of the available evidence does not allow obvious conclusion that amyloid,and especially tau protein,plays a key role in the etiology of AD(Morris et al.,2018).

关键词： Alzheimer tau ischemia

POSITIVE FUNCTIONALS ON ζ(R^n)

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Acta Mathematica Scientia 1990年第3期10卷 303-310页

作者： ryszard Grzaslewicz Inst.of Math. Tech.Univ.of WroclawWb.Wyspianskiegeo 2750-370 WroclawPoland

Let (E) be a space of operators on a finite dimensional Hilbert space E, and let (E) be its dual In this paper the positive part is considered for the unit ball of (E). We investigate the atructure of extremal subsets... 详细信息

关键词： Th POSITIVE FUNCTIONALS ON R~n

Ground movements modeling applying adjusted influence function

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International Journal of Mining Science and Technology 2020年第2期30卷 243-249页

作者： Agnieszka Malinowska ryszard Hejmanowski Huayang Dai AGH University of Science and Technology Al.Mickiewicza 3030059 KrakowPoland China University of Mining and Technology BeijingD11 Xueyuan Road100083 BeijingChina

Mathematical modeling of surface deformations caused by underground mining operation is commonly carried out with use of empirical,numerical or stochastic *** of the most frequently applied model for prediction of ground deformation in many countries is Knothe *** model developed by Knothe belongs to the stochastic methods and is based on the influence *** China a prediction method named Probability Integration Method(PIF)was established by Liu Baochen and Liao Guohua based on the stochastic medium *** version of that model allows to predict ground movements caused by mining operation in extremely complex technical and geological *** model is commonly applied for coal,metal ore and salt *** article presents several modifications of the mathematical model used in China and *** model is very widespread in the world,therefore the generalizations proposed in the article can be implemented for the purposes of prediction surface deformations for various types of deposits in many *** presented generalizations were then tested on specific examples of coal mining,copper ore mining and rock salt *** obtained results indicate high efficiency of methods based on the influence function in complex geological and mining conditions.

关键词： Mining operation Modeling of surface deformations Stochastic models Probability integration method Influence function Salt hard coal mining copper ore mining

Streamwise vortex generation by the rod

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Chinese Journal of Aeronautics 2019年第8期32卷 1903-1911页

作者： ryszard SZWABA Pawel FLASZYNSKI Piotr DOERFFER Department of Experimental Aerodynamics Institute of Fluid Flow Machinery Polish Academy of Sciences

The technology development related to aerodynamics is leading to ever increasing loads of wings, airfoils and turbine and compressor blades. The increase in aerodynamic forces is often leading to flow separation and depreciation of the aerodynamic performance of flying objects or propulsion systems. Flow control methods are required to avoid these negative effects. In the recent two decades the flow control by means of air-jet vortex generators has been also intensively investigated. In this method a streamwise vortex is introduced by an oblique jet. The necessity to supply air by a pipe system may be considered a disadvantage. In order to eliminate this feature, it has been proposed to put out a rod instead of a jet. It has been shown that the application of a rod can introduce the same effect as a jet, as long as the streamwise vortex generation is concerned and appropriate dimensions are used. The present paper focuses on the influence of rod vortex generators on a flow pattern downstream. The results presented here concern experimental and numerical investigations and provide guidelines for the design of a new flow control method dedicated mainly to external flows.

关键词： Air-jet vortex generator Boundary layer Flow control Rod vortex generator Streamwise vortices

Influence of Internal Channel Geometry of Gas Turbine Blade on Flow Structure and Heat Transfer

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Journal of Thermal Science 2017年第6期26卷 514-522页

作者： ryszard Szwaba Piotr Kaczynski Janusz Telega Piotr Doerffer Institute of Fluid-Flow Machinery Polish Academy of Sciences (IMP PAN) Fiszera 14 80-952 Gdansk POLAND

This paper presents the study of the influence of channel geometry on the flow structure and heat transfer, and also their correlations on all the walls of a radial cooling passage model of a gas turbine blade. The investigations focus on the heat transfer and aerodynamic measurements in the channel, which is an accurate representation of the configuration used in aeroengines. Correlations foi： the heat transfer coefficient and the pressure drop used in the design of internal cooling passages are often developed from simplified models. It is important to note that real engine passages do not have perfect rectangular cross sections, but include a comer fillets, ribs with fillet radii and a special orientation. Therefore, this work provides detailed fluid flow and heat transfer data for a model of radial cooling geometry which has very realistic features.

关键词： cooling internal blade channels aerodynamics with heat transfer