Validation of movement over a belt conveyor drum

This paper presents the use of new modern methods for the research of movement of material on a belt conveyor. One of the innovative methods is Particle Image Velocimetry (PIV), which was used to scan and assess the two-dimensional vector field of speed of particles on the belt conveyor. Outputs from PIV were compared to simulations of the same transport process. These simulations were performed using the Discrete Element Method (DEM). Four transport speeds of material were assessed for a real and simulative belt conveyor model. Software tracking of particle movement was used to determine and compare the trajectories of paths of particles leaving the belt conveyor drum. Validation of the DEM simulation of material movement over a belt conveyor drum using PIV provided acceptable results in the area of particle speed fields. Comparison of the particle path trajectory corresponds to the preliminary hypothesis which leads to calibration of the DEM simulation. The results and assessment of this paper were created based on validation.Web of Science11212411

Simulation of material flow through a sample divider

The prerequisite for a modem approach to innovative procedures of the development of current or even newly created equipment for the transport of particulate materials is the utilization of simulation methods, such as the Discrete Element Method (DEM). This article focuses on the basic, or initial, validation of movement of material through the sample divider. The mechanical-physical properties of brown coal were measured. Based on these parameters the preliminary input values for EDEM Academic were selected, and a simulation of the dividing process was run. The key monitored parameters included density and friction coefficient. Experiments on a realistic model of the equipment were performed and assessed. The total weights of brown coal at the exit from the divider were determined for a specific speed of the divider. The aim of this task was to simulate the realistically determined weight division of the brown coal sample. The result from the DEM was compared with the results of measurement on a realistic model.Web of Science12119919

Návrh rekonstrukce zásobníku slinku

Práce dodaná autorem není finální verzí dokumentu, proto není veřejně dostupnáBakalářská práce se zabývá metodikou řešení rekonstrukce zásobníku na sypké hmoty a to pro slinek (cement). V úvodu je popsáno rozdělení zásobníku, základní pojmy , vzorce pro technologický výpočet a měření. Na základě těchto informací je založeno řešení, je proveden technologický výpočet, vyroben zmenšený model zásobníku a změřen vzorek. Následně podle těchto naměřených a vypočítaných údajů jsou vytvořeny výkresy. Protokoly měření a výkresy jsou ve formě přílohy a jsou řešením této bakalářské práce.Prezenční342 - Institut dopravyNeuveden

Project of depiler for semi-finished steel products - slabs

Import 01/11/2007Prezenční342 - Institut doprav

Wood pellets transport with vibrating conveyor: Experimental for DEM simulations analysis

This work presents a comprehensive overview of the mechanical-physical parameters of the transport material affecting the vibratory transport. For this purpose, spruce pellets of different lengths, oak rods and spruce crush were tested. The determined parameters were particle size distribution and shape, internal friction, static and dynamic angle of repose. The samples were transported by a patented validation vibrating conveyor. Various settings were used. The results show that by changing the shape, it is possible to reduce friction or resistance as well as energy intensity during transport. It was observed that perfect shapes and lighter particles have lower friction, but a more pronounced bounce. Therefore, it does not form a typical pattern during transport, as in the case of an imperfectly shaped one. There is also included a simulation of the discrete element method. The study shows the possibility of the vibration machine where the material can be conveyed either directionally or sorted.Web of Science111art. no. 1660

The pelletization and torrefaction of coffee grounds, garden chaff and rapeseed straw

Waste biomass pelletization is a suitable process for obtaining energy dense solid fuel. If the pellets are further processed by torrefaction, both their qualitative and energy parameters are changed. Therefore, the objective of this study is to investigate the effect of the torrefaction process on pellets made from coffee grounds, garden chaff and rapeseed straw. Mechanical parameters, such as the pellet durability index, the wettability index of the pellets, their water moisture resistance, hardness, or specific and bulk density were determined for evaluation. Furthermore, pellet energy parameters such as the heat of combustion, calorific value, or elemental analysis were compared. Pelletization of the above-mentioned waste biomass and the torrefaction of the pellets were carried out in pilot plants. The first results showed that the torrefaction process for all samples increased the values of the heat of combustion or the values of the carbon content. The energy value of the pellets increases. The higher heating value of torrefied coffee ground pellets reached 26 MJ kg−1. The ash content also increases with these values. A simple energy balance has been carried out. Therefore, the study shows an insight into the energy use of coffee grounds and chaff from the garden compared to the results of the rapeseed straw pellets for the pelletization and torrefication process.Web of Science21035434

Characterization and flowability methods for metal powders

With the rise of additive technologies, the characterization of metal powders is increasingly required. There is a need to precisely match the properties of metal powders to a specific machine and to ensure highly consistent production. Therefore, the study aims at a detailed characterization of ten metal powders (Metal powder 316 L, Zn, Sn, Al, Cu, Mn, Fe, Bronze, Ti and Mo powder), for which the particle size distribution, morphology, static and dynamic angle of repose and the effective internal friction angle (AIFE) were determined. The AIFE parameter and flow index were determined from three commonly used rotary shear devices: The computer-controlled Ring Shear Tester RST-01. pc, the Brookfield PFT Powder Flow Tester and the FT4 Powder rheometer. The results showed that the values for the device of one manufacturer did not fully correspond to the values of another one. The flow characteristics of the metal powders were quantified from the particle size distribution data, static angle of repose, and AIFE data. According to the particle size distribution and angle of repose (AOR), 50% of the tested metal powders fell into the free-flowing mode. According to the evaluation of AIFE, 20% of the samples fell into the lower area. Based on the flow indexes calculated from the measurements of the shear devices used, 100% (RST-01.pc), 70% (PFT) and 50% (FT4) of the samples were included in the free-flowing category. When comparing the results, attention should be paid not only to the nature of the material, but also to the methodology and equipment used. A comparison of methodologies revealed similarities in the changing behavior of the different metal powders. A comparison of effective angles of AIFE and static AOR was shown, and a hypothesis of the conversion relation was derived.Web of Science101art. no. 2100

Zapis zachowania ziaren przy opuszczaniu zasobnika

The article focuses on behaviour of particular matter depending on marginal conditions with application of the PIV (Particle Image Velocimetry) and DEM (Discrete Element Method). The Discrete Element Method was used for validation of the particular matter behaviour. The research on the bulk material behaviour concentrated on detection of changes of velocity in experimental materials under constant marginal conditions. The marginal condition is an obstacle on the bottom of the storage tank. As experimental material, we selected glass balls of various sizes. The diameter of the particles was 5 and 3 mm. These particles were mixed in a 50/50 proportion up to the capacity of the experimental sample. The output velocity was recorded by a high-speed camera and compared with numerical simulation in the DEM program. The resulting values of the particle velocity in both the PIV and DEM method were compared. The agreement between the experimental outputs and the numerical method in comparison of the flow velocity was on a high level. From results is possible to detect the period when all particles left the tested zone from charts illustrating the average velocity of all particles in the selected areas during drainage of the tank. By comparison of the locations with the period of the flow's termination in the individual zones we can declare that in the course of the flow, the matter leaves the higher delimited zones earlier than zones closer to the outlet hole. The time difference of the mutually successive zones then becomes shorter while approaching the outlet hole. To summarize the whole experiment complexly, we can declare that the particular matter is accelerated towards the outlet hole by action of the 30 degrees incline of the hopper wall. In an area outside the outlet hole, this acceleration occurs especially in the x axis before the matter arrives above the discharge hole, where the core flow is under way and the direction of the matter's acceleration changes from the x axis to the y axis.W artykule skupiono się na zachowaniu pyłu zawieszonego w zależności od warunków brzegowych z użyciem anaklizatora obrazu cząstek (ang. skrót PIV – Particle Image Velocimetry) oraz metody elementów dyskretnych (ang. skrót DEM). Metody elementów dyskretnych użyto w celu określenia zachowania pyłu zawieszonego. Badanie materiału sypkiego skupione było na wykryciu zmian w prędkości materiału wysypującego się ze zbiornika, w stałych warunkach brzegowych. Jako materiał eksperymentalny użyto szklane kule o różnych średnicach. Średnice wynosiły 5 oraz 3 mm. Kule wymieszano w proporcji 50/50, aż do osiągnięcia objętości próbki eksperymentalnej. Prędkość wyjściowa została zarejestrowana przez kamerę i porównana z symulacją numeryczną w programie DEM. Porównano uzyskane wyniki określenia prędkości cząstek z obu metod PIV i DEM. Zalezność między wynikami eksperymentalnymi i prędkością strumienia wyznaczoną metodą numeryczną była na wysokim poziomie. Dzięki wynikom z wykresów przedstawiających średnią prędkość cząstek na wybranych powierzchniach można określić moment, w którym wszystkie cząstki opuściły badaną przestrzeń. Można stwierdzić, że w przepływ strumienia materiału opuszczającego zbiornik niejest jednolity. Można stwierdzić, że pył zawieszony przyspiesza w kierunku odbioru, przy 30° kącie nachylenia ściany zbiornika.Web of Science220620