Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 4
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

The non-stationary problem of temperature distribution in a circular cylindrical channel of infinite length filled with a homogeneous biomass material moving with a constant velocity in the axial direction was investigated. The heat source was a shaftless helical screw (or auger), which was heated with an electric current due to the Joule–Lenz effect and rotated uniformly around the axis of symmetry of the channel. Similar problems arise in the thermal processing of biomaterials using screw conveyor in pyrolysis and mass sterilization and pasteurization of food products. The problem is solved using the expansion of given and required functions in Fourier series over angular coordinate and integral Fourier and Laplace transforms over axial coordinate and time, respectively. As a result, the temperature field is obtained as the sum of two components, one of which, global, is proportional to time, and the other, which forms the microstructure of the temperature profile, is given by Fourier–Bessel series. The coefficients of the series are determined by the integrals calculated using the Romberg method. Based on the numerical calculations, the analysis of the space-time microstructure of the temperature field in the canal was performed. A significant dependence of the features of this microstructure on the geometric, kinematic and thermodynamic characteristics of the filling biomass and the screw was revealed.
Go to article

Bibliography

Abramowitz M., Stegun I.A. (Eds), 1972. Handbook of mathematical functions with formulas, graphs, and mathematical tables. Dover Publ., Inc., New York.

Aramideh S., Xiong Q., Kong S.C., Brown R.C., 2015. Numerical simulation of biomass fast pyrolysis in an screw reactor. Fuel, 156, 234–242. DOI: 10.1016/j.fuel.2015.04.038.

Biogreen, 2016. The pyrolyzer Spirajoule®. Available at: https://www.biogreen-energy.com/spirajoule.

Bortolamasi M., Fottner J., 2001. Design and sizing of screw feeders. PARTEC 2001, International Congress for Particle Technology. Nuremberg, Germany, 27–29 March 2001.

Campuzano F., Brown R.C., Martínez J.D., 2019. Auger reactors for pyrolysis of biomass and wastes. Renewable Sustainable Energy Rev., 102, 372–409. DOI: 10.1016/j.rser.2018.12.014.

Carleton A.J., Miles J.E.P., Valentin F.H.H., 1969. A study of factors affecting the performance of screw conveyers and feeders. J. Eng. Ind., 91, 329-333. DOI: 10.1115/1.3591565.

Carslaw H.S., Jaeger J.C., 1959. Conduction of heat in solids. Clarendon Press, Oxford.

Cheney W., Kincaid D., 2008. Numerical mathematics and computing. Thomson Brooks/Cole, Belmont.

ETIA S.A.S., 2019. Thermal processing of bulk and powders powered by electricity. Available at: https://etiagroup. com/operations-for-thermal-processing.

Evstratov V.A., Rud A.V., Belousov K.Y., 2015. Process modelling vertical screw transport of bulk material flow. Procedia Eng., 129, 397–402. DOI: 10.1016/j.proeng.2015.12.134.

Guda V.K., Steele P.H., Penmetsa V.K., Li Q., 2015. Fast pyrolysis of biomass: Recent advances in fast pyrolysis technology, In: Pandey A., Bhaskar T., Stöcker M., Sukumaran R. (Eds.), Recent advances in thermochemical conversion of biomass. Elsevier, Amsterdam etc., 175-211.

Henan Pingyuan Mining Machinery, 2015. What factors that affect the screw conveyor conveying efficiency? Available at: https://www.pkmachinery.com/faq/factors–affect–screw-conveyor-conveying-efficiency.html.

Korn G.A., Korn T.U., 2000. Mathematical handbook for scientists and engineers: Definitions, theorems and formulas for references and review. Dover Publ., Inc., Mineola, New York.

Kovacevic A., Stosic N., Smith I., 2007. Screw compressors: Three dimensional computational fluid dynamics and solid fluid interaction. Springer-Verlag, Heidelberg, Berlin, New York. DOI: 10.1007/978-3-540-36304-0.

Krein S.G. (Ed.), 1972. Functional analysis. Wolters-Noorhoff Publ., Groningen.

Ledakowicz S., Stolarek P., Malinowski A., Lepez O., 2019. Thermochemical treatment of sewage sludge by integration of drying and pyrolysis/autogasification. Renewable Sustainable Energy Rev., 104, 319–327. DOI: 10.1016/j.rser.2019.01.018.

Lepez O., Sajet P., 2009. Patent No. WO 2009/095564 A3. Device for the thermal processing of divided solids. Luikov A.V., 1968. Analytical heat diffusion theory. Acad. Press, New York etc.

Martelli F.G., 1983. Twin-screw extruders: A basic understanding. Van Nostrand Reinhold Co, New York.

Martínez J.D., Murillo R., Garcia T., Veses A., 2013. Demonstration of the waste tire pyrolysis process on pilot scale in a continuous screw reactor. J. Hazard. Mater., 261, 637–645. DOI: 10.1016/j.jhazmat.2013.07.077.

Nachenius R.W., Van De Wardt T.A., Ronsse F., Prins W., 2015. Residence time distributions of coarse biomass particles in a screw conveyor reactor. Fuel Process Technol, 130, 87–95. DOI: 10.1016/j.fuproc.2014.09.039.

Shi X., Ronsse F., Roegiers J., Pieters J.G., 2019a. 3D Eulerian-Eulerian modeling of a screw reactor for biomass thermochemical conversion. Part 1: Solids flow dynamics and back-mixing. Renewable Energy, 143, 1465-1476. DOI: 10.1016/j.renene.2019.05.098.

Shi X., Ronsse F., Nachenius R., Pieters J.G., 2019b. 3D Eulerian-Eulerian modeling of a screw reactor for biomass thermochemical conversion. Part 2: Slow pyrolysis for char production. Renewable Energy, 143, 1477-1487. DOI: 10.1016/j.renene.2019.05.088.
Go to article

Authors and Affiliations

Stanisław Ledakowicz
1
ORCID: ORCID
Olexa Piddubniak
1

  1. Faculty of Process and Environmental Engineering, Lodz University of Technology, Wolczanska St. 215, 90-924 Lodz, Poland
Download PDF Download RIS Download Bibtex

Abstract

Significant subsoil deformation and additional loads from the new denitrification unit caused a major problem with the load-bearing capacity of the coal power plant. It was necessary to perform an advanced assessment of the technical condition of the structure. Laser scanning (LiDAR) were used to obtain detailed data upon structure. Based on the analysis of the point cloud, the location of the column axes was determined, which allowed to determine the global and local displacements of the structure. Spatial models of the structure were created. Non-linear analyses of the structure were carried out using two types of models: 1) global beam-shell 3D models of the boiler room used to calculate the magnitude of internal forces and deformations of the structure; 2) local beam-shell detailed models of selected structural elements. Based on the results of the calculations, necessary reinforcement of the structure was designed and successfully implemented. Advanced analysis of the structure using laser scanning, subsoil monitoring and complex numerical models made it possible to perform only local reinforcements of the entire complex structure.
Go to article

Authors and Affiliations

Szymon Skibicki
1
ORCID: ORCID
Tomasz Wróblewski
1
ORCID: ORCID
Wiesław Paczkowski
1
ORCID: ORCID
Krzysztof Kozieł
2
ORCID: ORCID
Marcin Matyl
2
ORCID: ORCID
Maciej Wisniowski
3
ORCID: ORCID

  1. West Pomeranian University of Technology in Szczecin, Faculty of Civil and Environmental Engineering, al. Piastów 50a, 70-311 Szczecin, Poland
  2. Optimal Design of Structures Krzysztof Kozieł, ul. Na Piasku 12a, 44-122 Gliwice, Poland
  3. Silesian University of Technology, Faculty of Civil Engineering, ul. Akademicka 2A, 44-100 Gliwice, Poland
Download PDF Download RIS Download Bibtex

Abstract

The phenomenon of the so-called Polish monumental theatre has for nearly a century resisted attempts at conceptualization. Created by artists living in a transitional period and formed in a peculiar “trans-era” mental space, this theatre was wrought from a hybrid substance that combined a Romantic and post-Romantic content with an avant-garde form. Being “simultaneously national and supra-national”, it appeared as a unique conceptual and artistic construct; a construct that was touted as the innovative Polish input into the reform of European theatre. Owing to the heterogeneity of its subject-matter, it was at times included into, and at other times excluded from the body of endeavours of an avant-garde nature; the correct categorization was until now made difficult by the conceptual template constructed around the dogma concerning the incompatibility of the two areas: the avant-garde and the so-called national duties. Seen in the perspective of modern-day research on the variegated nature of Modernism and on its inner tensions, however, this phenomenon may emerge as an interesting illustration of the synthesizing efforts of Modernism.
Go to article

Authors and Affiliations

Joanna Stacewicz-Podlipska
1
ORCID: ORCID

  1. Instytut Sztuki PAN
Download PDF Download RIS Download Bibtex

Abstract

The paper is concerned with one of the internal forces driving the progress of lyrical discourse. Its nature consists in that initially, some linguistic and/or cognitive deviation appears in the poem, and next the author undertakes a series of attempts at its adjustment or mitigation. More often than not these attempts are increasingly successful, but at some later point they, for various reasons, stop to be rewarding. This tends to happen either at the end of the text, where the most important truth is prototypically discovered, or immediately before the final fragment. In both cases, the completion of the relevant ‘adjustment’ theme plays a significant compositional role. Discussed at some length are the implications of our analysis for the theory of discourse relations. The bulk of the instances under examination are drawn from O. Mandelstam’s verse.
Go to article

Authors and Affiliations

Gennadij Zeldowicz
1
ORCID: ORCID

  1. Warszawa, Uniwersytet Warszawski

This page uses 'cookies'. Learn more