NUMERICAL AND EXPERIMENTAL ANALYSIS OF A CENTRIFUGAL PUMP WITH DIFFERENT ROTOR GEOMETRIES

The paper presents a comparative analysis of the operation of two variants of centrifugal pump rotors, a description of the main parameters, and the influence of the blade geometry on the performance characteristics obtained. Rotors have been designed using the arc and point method. Based on the developed 3D CAD models, the rotors were printed using the rapid prototyping method on a 3D printer in FFF (Fused Filament Fabrication) technology, in order to experimentally verify the performance, by placing them on the Armfield FM50 test stand. The analysis part of the CFD includes a fluid flow in Ansys Fluent. The process of creating a flow domain and generating a structural mesh was described, along with the definition of boundary conditions, the definition of physical conditions and the turbulence model. The distribution of pressures and velocities in the meridional sections is shown graphically. The chapter with the experimental analysis contains a description of the measuring stand and the methodology used. The results obtained made it possible to generate the characteristics, making it possible to compare the results received. The results allowed to note the influence of geometry on the behavior of the rotors during operation in the system and to indicate that the arc rotor gets a 7% higher head and 2% higher efficiency than the point method rotor, which gives the basis for its commercial use in industry

Lignin and Starch Derivatives with Selenium Nanoparticles for the Efficient Reduction of Dyes and as Polymer Fillers

Selenium nanoparticles (SeNPs) were synthesized and stabilized by biopolymers, namely, sodium lignosulfonate (LS) and starch sodium octenyl succinate (OSA). The obtained selenium nanoparticles were studied for their catalytic activity in the reduction of a dye (C.I. Basic Blue 9, methylene blue) by sodium borohydride. The SeNPs-OSA and SeNPs-LS nanoparticles were also dispersed in a photosensitive matrix and studied as polymer composites. The research confirmed the catalytic abilities of the prepared SeNPs in the reduction of the organic dye. Mechanical tests on the polymers and their composites showed an improvement in the composites’ strength in all tested cases. An increase in hardness and Young’s modulus values of the filled materials compared to the pure matrix was found as well.</p

Study of the relationships between multi-hole, multi-disc mill performance parameters and comminution indicators

The knowledge of a grinder structure, its performance parameters and characteristics of biomaterials breakage are crucial for this research whose aim is to determine the dependencies between performance parameters and comminution indicators. The aim of this study is to investigate the relationships between multi-disc mill performance parameters such as discs angular speed, batch dosing speed and comminution characteristics: power consumption, specific energy consumption, throughput and size reduction ratio. To achieve these goals, an experiment was conducted on a five-disc mill with a special monitoring system. The research program was established, with disc angular speed at different configurations and different batch dosing speeds. The results show that power consumption, specific energy consumption and size reduction ratio depend on the total increase in angular speed of discs S Delta omega in such a way that an increase in S Delta omega causes an increase in the abovementioned comminution indicators. In turn, an increase in batch dosing speed W causes an increase in throughput. The fitting curves of comminution indicators in dependence of selected performance parameters are also presented in this study.Web of Science1315art. no. 826

New Trends in Substrates and Biogas Systems in Poland

The amendment to the Polish Renewable Energy Act creates great opportunities for the development of the biogas market in Poland. Years of experience in biogas production in Western Europe and the development of biogas installations in Poland indicate the requirement to look for alternative substrates to those produced from dedicated crop production (mainly maize silage). Feasible solutions include the use of biodegradable waste from agriculture or industry as well as municipal landfill sites. The usage of these substrates in the methane fermentation process offers low cost, high biogas production and the safe management of biowaste. The arguments for using them in biogas installations are persuasive. This article presents new approaches of biogas plant installation solutions which allows for the effective fermentation of biowaste from animal and vegetable production, from the agro-food industry and from municipal wast

Analysis of flow through channel with mounted blades

Numerical analysis of parts of the installation for transporting the mixture. The mixture consists of sand, stones and water. The analysis concerns the possibility of reducing the flow velocity of the mixture in the installation by means of installing the blades. The article presents an analysis of 10 blades that have been simulated. Speed distributions are presented after passing through the blades and determined which slows the speed of the mixture to the best possible extent

Measurements and Analysis of the Physical Properties of Cereal Seeds Depending on Their Moisture Content to Improve the Accuracy of DEM Simulation

This article presents the results of research on the influence of moisture on changes in the physical properties, i.e., the length, width, thickness, and weight, of dressed and untreated cereal seeds in order to improve the simulation process based on the discrete element method (DEM). The research was conducted on the seeds of three winter cereals, i.e., triticale, rye, and barley. The seeds with an initial moisture content of about 7% were moistened to five levels, ranging from 9.5% to 17.5%, at an increment of 2%. The statistical analysis showed that moisture significantly influenced the physical properties of the seeds, i.e., their length, width, thickness, and weight. As the moisture content of the seeds increased, there were greater differences in their weight. The average increase in the thousand kernel weight resulting from the increase in their moisture content ranged from 4 to 6 mg. The change in the seed moisture content from 9.5% to 17.5% significantly increased the volume of rye seeds from 3.10% to 14.99%, the volume of triticale seeds from 1.00% to 13.40%, and the volume of barley seeds from 1.00% to 15.33%. These data can be used as a parameter to improve the DEM simulation process

The Application of Optoelectronic Elements to Control the Sowing Process

The article is an overview of scientific and patent literature as well as solutions available on the world market of electronic equipment for seed drills. Recently Dickey-John and Väderstad, which offers the SeedEye system, have been leading companies in this branch. Photoelectric sensors, which do not interfere with the seed flow, are often used to count seeds and control the correctness of sowing. The article describes and presents the results of simulation and laboratory tests of two original innovative concepts of a photoelectric sensor: 1 – with an infrared diode and a centrifugal seed stream concentrator, 2 - laser multi-reflection senso

PVDF Piezoelectric Sensors for Seeds Counting and Coulter Clogging Detection in Sowing Process Monitoring

The paper presents the results of a test on the use of piezoelectric sensors made of PVDF foil for counting grain and checking clogging in the sowing drill. The tests were carried out in a simulator of the sowing drill with the use of a measuring system with high input impedance. Two kinds of barley and triticale grains were investigated. Measurements were carried out for different feeding frequencies. On the basis of the signals recorded, an algorithm of counting the sown grain was developed and tested. The algorithm is based on signal statistic comparison in adjacent windows. The developed algorithm allows counting more than 90% of the sown grains

An overview of technical parameters and functional features of universal seed drills. Part 1. Mechanical seed drills

Dokonano przeglądu parametrów technicznych i cech użytkowych wybranych uniwersalnych siewników mechanicznych producentów krajowych. Ponadto szczegółowo przeanalizowano istotne parametry i cechy mające bezpośredni wpływ na jakość zabiegu siewu nasion.The article is an overview of the technical parameters and functional features of selected Polish universal mechanical seed drills. It also includes a detailed analysis of important parameters and features with direct impact on the quality of the seed sowing procedure

Computer Aided Modeling of Wood Chips Transport by Means of a Belt Conveyor with Use of Discrete Element Method

The effectiveness and precision of transporting wood chips on the transport trailer or hopper depends on an inclination angle, a conveyor belt speed, and length. In order to devise a methodology aiding designing and the selection of technical and performance parameters (aiding the settings of conveyor belt sub-assemblies), the authors carried out the simulation tests concerning wood chips transport on the belt conveyor and their outlet. For the purposes of these tests, a simulation model was performed in the Rocky DEM (discrete element method) software in the numerical analysis environment and compared to analytical tests. The tested wood chips were taken from cherry plum branches chipping processes (Prunus cerasifera Ehrh. Beitr. Naturk. 4:17. 1789 (Gartenkalender 4:189-204. 1784)), out of which seven basic fractions were separated, which differed mainly in terms of their diameter from 5 mm to 50 mm and the length of 150 mm. The article presents the results of wood chips ejection distance in the form of the 3D functions of wood chips ejection distance depending on the conveyor belt inclination angle and belt speed. The results are presented for five conveyor belt lengths (1 m, 2 m, 3 m, 4 m, 5 m). The tests also involved the conveyor belt inclination angle in the range from 10&deg; to 50&deg; and the belt velocity in the range from 1 m/s2 to 5 m/s2. The numerical test results demonstrate higher average values of wood chips ejection distance than designated in the analytical model. The average arithmetical difference in the results between the numerical and analytical model is at the level of 13%