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EN
Rapeseed by-products of seeds de-oiling, particularly expellers and post-extracted meal, are currently considered an important biomass that can be used as an alternative energy source, either in raw form or after conversion to biochar. Rapeseed biomass represents a difficult-to-handle cargo, mainly due to its sensitivity to mechanical, climatic, and biological impacts, as well as its dusty nature. This study aims to determine the physical properties of rapeseed meals and their fractions. Morphological and chemical features of six particle sets are investigated in order to explain the variation in their physical properties having importance in handling and transportation processes. The true density of fractions increases when the particle size decreases due to the diminishing quantitative share of seed coats. No correlation is observed between true and bulk densities, as the particle shape, surface sculpture, and adhesion affect the mutual particle arrangements. Along with a decrease in the particle size from 0.4 mm, a rapid decrease in the flowability is observed. The tendency of the finest dust (d < 0.075 mm) to form agglomerated complexes causes its lower bulk density, higher porosity, and higher angles of repose in comparison to coarse dust (0.075–0.4 mm). It is concluded that a relatively low tendency to free flowing of natural RSM is mainly caused by its wide-ranging particle size distribution and their geometry differentiation, which facilitate mutual particle interlockings. The known cases of blockages of silos, bins, hoppers, and transfer chutes may be mainly caused by the powder fractions (< 0.2 mm), with a much lower flowability than other particles.
EN
Computer simulation of bulk materials behavior, including comminution and fragmentation, using DEM has been growing fast, recently. One of the important tasks to get the reliable simulation results is to provide proper materials and contact parameters, which need to be determined in a series of laboratory experiments. For comminution simulation the additional parameters describing the breakage probability and breakage functions are necessary. While some simulation parameters are available in the literature for brittle materials, valid data are lacking for biomaterials such as cereal, rice or corn grains, especially for comminution parameters. The aim of this study was to present the calibration approach and determination of materials, contact, interaction and breakage parameters for grainy biomaterials. The calibration process was done for rice and corn grains. The calibration approach consists of grains size distribution and shape characterization, friction and restitution coefficient determination, and breakage probability description. Based on the results of the experiments, the models were created in the DEM software. The result was the set of calibrated parameters for rice and corn grains.
EN
The literature is flooded with scientific information on most durability properties except water absorption coefficient of masonry units like sandcrete blocks. Also, while waste papers disposal is a systemic problem due to ineffectiveness of waste management system in developing countries, the price of cement is on the increase. This situation, ultimately, causes a bane in achievement of low-cost housing development considering the fact that sandcrete blocks are predominantly used as walling elements for such undertakings. In this study, solid core sandcrete blocks were produced with waste paper ash (WPA) utilized as partial replacement of cement at 5 % and 10 % volumetric levels. Chemically, the WPA was found to show similarity with cement in terms of SiO2, Al2O3, and CaO contents. Density and water absorption coefficient of the block samples were determined. While density ranged from 1682 to 1872 kg/m3, water absorption coefficient varied from 27.04 to 23.49 kg/m2h0.5. Statistically, no significant difference was revealed at 𝑝<0.05 between experimentally-measured water absorption coefficients and those obtained using the model developed for prediction based on density of the samples. Thus, utilization of WPA as described herein could help to reduce the cost of procuring cement and in turn, enhance low-cost building construction. Also, with the developed model (showing dependence of water absorption coefficient on density), durability of sandcrete blocks exposed to moisture –prone environment could be easily predicted.
EN
The paper deals with various types of buckwheat products (Fagopyrum esculentum Moench), which have been determined with mechanical and physical properties in order to provide useful data for engineers to design structures of used equipment, harvesting and other processing technologies. Buckwheat is currently a well-sought-after food in the field of healthy nutrition, especially because of its high fiber content, iron and potassium. Among the tested samples were, for example, buckwheat hazelnuts, chips, flakes and others. In the above mentioned, the parameters of the linear dimensions, the Carrs index, the Hausner ratio and the flow rate were measured and compared. The influence of geometric parameters of buckwheat products was determined on mechanical and physical properties. The first results showed that the set parameters were statistically different for each type of buckwheat. On the basis of measured data, a simulation of the flow of a specific buckwheat sample was performed. The discrete element (DEM) method used for this purpose appears to be an appropriate tool for transporting these agricultural products.
PL
Artykuł dotyczy różnych rodzajów produktów z gryki (Fagopyrum esculentum Moench), które zostały określone za pomocą właściwości mechanicznych i fizycznych w celu dostarczenia inżynierom przydatnych danych do projektowania struktur używanych urządzeń, zbiorów i innych technologii przetwarzania. Gryka jest obecnie popularnym pożywieniem w dziedzinie zdrowego żywienia, szczególnie ze względu na wysoką zawartość błonnika, żelaza i potasu. Wśród badanych próbek były orzechy laskowe, gryka, chipsy, płatki i inne. Zmierzono i porównano parametry wymiarów liniowych, wskaźnik Carrsa, współczynnik Hausnera i natężenie przepływu. Określono wpływ parametrów geometrycznych produktów z gryki na właściwości mechaniczne i fizyczne. Wyniki wykazały, że zmierzone i założone parametry były statystycznie różne dla każdego rodzaju gryki. Na podstawie zmierzonych danych przeprowadzono symulację przepływu określonej próbki gryki. Zastosowana w tym celu metoda elementów dyskretnych (DEM) wydaje się odpowiednim narzędziem do opisu transportu tych produktów rolnych.
EN
The influence of external factors on changes in the soybean meal quality features has an important meaning in the emergence of hazards during the transport processes of this cargo. Soybean meal is one of the most frequently used components of fodder mixtures. Due to its inherent properties, it is classified as special cargoes. Maintaining the quality of soybean meal during transport processes depends on storage, handling and transport conditions. The main external factor included in the study was humidity. Transport-technological quality features were distinguished: kinetic angle of repose, size of particles, bulk density, porosity. The article presents the results of research on soybean meal and its separated fractions. There was presented humidity influence on changes in significant features for this cargo. Type and range of changes in the distinguishing features of soybean meal were determined in the given stages of the transport chain under the influence of humidity. The risk was assessed in the transport processes of soybean meal. A correlation was determined between changes of individual features and water content in soybean meal changing as a result of air humidity. It was found that humidity of the ambient air in which transport processes occur and size of grain particles of soybean meal have a significant impact on changes in transport-technological quality features.
EN
This paper analyzed the effect of moisture content on selected physical properties of Astoria variety wheat grain using six levels of grain moisture content (14%, 16%, 18%, 20%, 22% and 24%). The following were determined for each level of moisture content: angle of repose, static angle of repose (SAR), bulk density and thousand kernel weight. The friction coefficients for four different construction materials (CEF) were also determined: acid-resistant steel, wear-resistant steel, plastic (PPLD) and rubber. It was found that an increasing moisture content in grains was accompanied by an increase in the thousand kernel weight, angle of repose, SAR, as well as the CEF against each of the surfaces used in the study. The highest value of the CEF was recorded for a rubber surface (0.782) and the smallest was for a polypropylene surface (0.443). The highest values of the angle of repose and the SAR were recorded for the grain with the highest moisture content: 37.15o and 39.44o, respectively. An increase in the moisture content in kernels reduced their bulk density from 79.870 kg · hl–1 (moisture content: 14%) to 68.783 kg · hl–1 (moisture content 24%).
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EN
The paper examines the selected physical properties of seeds of 8 plants used in agri-food processing industry. These are: winter rapeseed (Brassica napus L.) Adriana cultivar, sesame (Sesamumindicum L.), common flax (Linum usitatissimum L.) Luna cultivar, husked sunflower (Helianthus L.) (country of origin – Bulgaria), hemp (Cannabis sativa L.) Benikocultivar, blue poppy (Papaver somniferum L.) Major cultivar, garden cress (Lepidium sativum L.), black caraway (Nigella Sativa L.). In the research material we determined the following: mass of thousand seeds (MTS), piling angle and angle of repose, tap and bulk density and compressive resistance of single seeds. Some seeds from the selected plant species differed with shape and size. Thus, the results determining the physical properties were varied.
PL
W pracy zbadano wybrane właściwości fizyczne nasion 8 roślin wykorzystywanych w przetwórstwie rolno-spożywczym, takich jak: rzepak ozimy (Brassica napus L.) odmiany Adriana, sezam indyjski (Sesamum indicum L.), len zwyczajny (Linum usitatissimum L.) odmiany Luna, słonecznik łuskany (Helianthus L.) (kraj pochodzenia – Bułgaria), konopie siewne (Cannabis sativa L.) odmiany Beniko, mak niebieski (Papaver somniferum L.) odmiany Major, rzeżucha ogrodowa (Lepidium sativum L.), czarnuszka siewna (Nigella Sativa L.). W materiale badawczym oznaczono: masę 1000 nasion (MTS), kąt zsypu i usypu nasion, gęstość utrzęsioną i usypową nasion oraz wytrzymałość pojedynczych nasion na ściskanie. Niektóre nasiona spośród wybranych gatunków roślin różniły się między sobą zarówno kształtem jak i wielkością, stąd też wyniki oznaczeń właściwości fizycznych były zróżnicowane.
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