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

Deflection of balancing disc in a multistage centrifugal pump, being the consequence of pressure forces, causes the change of shape of the axial clearance between the rotating balancing disc and the stationary counterdisc. It results in reduction of axial force acting on the rotating wall of the clearance, and the total balancing force. The final effect is a significant decrease (e.g. of 20%) of disc to counterdisc distance. The approximate formulae for radial pressure distribution in turbulent flow through hydraulically smooth conical axial clearance are derived in the paper and a numerical example is given. The method of integral relations was applied.
Go to article

Authors and Affiliations

Waldemar Jędral
Download PDF Download RIS Download Bibtex

Abstract

According to Falkum (2011: 9), it is apparent that a single word form can be associated with several different meanings. We may take the selected word for our elaboration, which is run. Its meaning in the verb phrase run a half marathon is apparently different from the one it has in run some water, or, for that matter, in run on gasoline, run on empty, run a shop, run late, run away from responsibilities, run in the family, run for President, etc. This phenomenon, described as polysemy, proliferates in natural languages, including English as well. This is confi rmed by a range of different senses (and/or uses) that any available source, e.g. any dictionary will have listed under a polysemous term a considerable number of its entries. The objective of this article will be the theoretical analysis related to the notion of polysemy. The subsequent sections of the article will comprise the practical demonstration of the results of the corpus study. Its subjects were Polish students of English Philology. The students’ use of a selected polysemous word run was investigated based on the available corpus PELCRA1. The corpus was selected as it is a very reliable source to investigate the use of L2 from the perspective of non-native Polish users of English. To demonstrate how the students comprehend the selected polysemous word run, the extracts from students’ compositions, essays and short stories were analysed in accordance with the occurrence of the word run and supplemented with their performance during the spoken mode. The extracts were subsequently analysed in light of their use and assumed awareness of the investigated word.
Go to article

Authors and Affiliations

Artur Świątek
Download PDF Download RIS Download Bibtex

Abstract

Is the category of “becoming” relative? This question accompanies the considerations undertaken in this article. It is the starting point for the reflection on the understanding of the designations of the expression “to become” in the metaphysical, epistemological and linguistic aspects. The results of this reflection are to serve adequate interpretations of the text. In the applicative part of the article both the fundamentals of text interpretation and the risks resulting from different cognitive perspectives are discussed. The source of these risks is seen primarily in misunderstanding the essence and the category of becoming.
Go to article

Authors and Affiliations

Grzegorz Pawłowski
1
ORCID: ORCID

  1. Uniwersytet Warszawski
Download PDF Download RIS Download Bibtex

Abstract

This paper presents a design of a tracked in-pipe inspection mobile robot with an adaptive drive positioning system. The robot is intended to operate in circular and rectangular pipes and ducts, oriented horizontally and vertically. The paper covers a design process of a virtual prototype, focusing on track adaptation to work environment. A mathematical description of a kinematic model of the robot is presented. Operation of the prototype in pipes with a cross-section greater than 210 mm is described. Laboratory tests that validate the design and enable determination of energy consumption of the robot are presented.

Go to article

Bibliography

[1] A. Valera-Medina, A. Giles, D. Pugh, S. Morris, M. Pohl, and A. Ortwein. Investigation of combustion of emulated biogas in a gas turbine test rig. Journal of Thermal Science, 27:331–340, 2018. doi: 10.1007/s11630-018-1024-1.
[2] K. Tanaka and I. Ushiyama. Thermodynamic performance analysis of gas turbine power plants with intercooler: 1st report, Theory of intercooling and performance of intercooling type gas turbine. Bulletin of JSME, 13(64):1210–1231, 1970. doi: 10.1299/jsme1958.13.1210.
[3] H.M. Kwon, T.S. Kim, J.L. Sohn, and D.W. Kang. Performance improvement of gas turbine combined cycle power plant by dual cooling of the inlet air and turbine coolant using an absorption chiller. Energy, 163:1050–1061, 2018. doi: 10.1016/j.energy.2018.08.191.
[4] A.T. Baheta and S.I.-U.-H. Gilani. The effect of ambient temperature on a gas turbine performance in part load operation. AIP Conference Proceedings, 1440:889–893, 2012. doi: 10.1063/1.4704300.
[5] F.R. Pance Arrieta and E.E. Silva Lora. Influence of ambient temperature on combined-cycle power-plant performance. Applied Energy, 80(3):261–272, 2005. doi: 10.1016/j.apenergy.2004.04.007.
[6] M. Ameri and P. Ahmadi. The study of ambient temperature effects on exergy losses of a heat recovery steam generator. In: Cen, K., Chi, Y., Wang, F. (eds) Challenges of Power Engineering and Environment. Springer, Berlin, Heidelberg, 2007. doi: 10.1007/978-3-540-76694-0_9.
[7] M.A.A. Alfellag: Parametric investigation of a modified gas turbine power plant. Thermal Science and Engineering Progress, 3:141–149, 2017. doi: 10.1016/j.tsep.2017.07.004.
[8] J.H. Horlock and W.A. Woods. Determination of the optimum performance of gas turbines. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 214:243–255, 2000. doi: 10.1243/0954406001522930.
[9] L. Battisti, R. Fedrizzi, and G. Cerri. Novel technology for gas turbine blade effusion cooling. In: Proceedings of the ASME Turbo Expo 2006: Power for Land, Sea, and Air. Volume 3: Heat Transfer, Parts A and B. pages 491–501. Barcelona, Spain. May 8–11, 2006. doi: 10.1115/GT2006-90516.
[10] F.J. Wang and J.S. Chiou. Integration of steam injection and inlet air cooling for a gas turbine generation system. Energy Conversion and Management, 45(1):15–26, 2004. doi: 10.1016/S0196-8904 (03)00125-0.
[11] Z. Wang. 1.23 Energy and air pollution. In I. Dincer (ed.): Comprehensive Energy Systems, pp. 909–949. Elsevier, 2018. doi: 10.1016/B978-0-12-809597-3.00127-9.
[12] Z. Khorshidi, N.H. Florin, M.T. Ho, and D.E. Wiley. Techno-economic evaluation of co-firing biomass gas with natural gas in existing NGCC plants with and without CO$_2$ capture. International Journal of Greenhouse Gas Control, 49:343–363, 2016. doi: 10.1016/j.ijggc.2016.03.007.
[13] K. Mohammadi, M. Saghafifar, and J.G. McGowan. Thermo-economic evaluation of modifications to a gas power plant with an air bottoming combined cycle. Energy Conversion and Management, 172:619–644, 2018. doi: 10.1016/j.enconman.2018.07.038.
[14] S. Mohtaram, J. Lin, W. Chen, and M.A. Nikbakht. Evaluating the effect of ammonia-water dilution pressure and its density on thermodynamic performance of combined cycles by the energy-exergy analysis approach. Mechanika, 23(2):18110, 2017. doi: 10.5755/j01.mech.23.2.18110.
[15] M. Maheshwari and O. Singh. Comparative evaluation of different combined cycle configurations having simple gas turbine, steam turbine and ammonia water turbine. Energy, 168:1217–1236, 2019. doi: 10.1016/j.energy.2018.12.008.
[16] A. Khaliq and S.C. Kaushik. Second-law based thermodynamic analysis of Brayton/Rankine combined power cycle with reheat. Applied Energy, 78(2):179–197, 2004. doi: 10.1016/j.apenergy.2003.08.002.
[17] M. Aliyu, A.B. AlQudaihi, S.A.M. Said, and M.A. Habib. Energy, exergy and parametric analysis of a combined cycle power plant. Thermal Science and Engineering Progress. 15:100450, 2020. doi: 10.1016/j.tsep.2019.100450.
[18] M.N. Khan, T.A. Alkanhal, J. Majdoubi, and I. Tlili. Performance enhancement of regenerative gas turbine: air bottoming combined cycle using bypass valve and heat exchanger—energy and exergy analysis. Journal of Thermal Analysis and Calorimetry. 144:821–834, 2021. doi: 10.1007/s10973-020-09550-w.
[19] F. Rueda Martínez, A. Rueda Martínez, A. Toleda Velazquez, P. Quinto Diez, G. Tolentino Eslava, and J. Abugaber Francis. Evaluation of the gas turbine inlet temperature with relation to the excess air. Energy and Power Engineering, 3(4):517–524, 2011. doi: 10.4236/epe.2011.34063.
[20] A.K. Mohapatra and R. Sanjay. Exergetic evaluation of gas-turbine based combined cycle system with vapor absorption inlet cooling. Applied Thermal Engineering, 136:431–443, 2018. doi: 10.1016/j.applthermaleng.2018.03.023.
[21] A.A. Alsairafi. Effects of ambient conditions on the thermodynamic performance of hybrid nuclear-combined cycle power plant. International Journal of Energy Research, 37(3):211–227, 2013. doi: 10.1002/er.1901.
[22] A.K. Tiwari, M.M. Hasan, and M. Islam. Effect of ambient temperature on the performance of a combined cycle power plant. Transactions of the Canadian Society for Mechanical Engineering, 37(4):1177–1188, 2013. doi: 10.1139/tcsme-2013-0099.
[23] T.K. Ibrahim, M.M. Rahman, and A.N. Abdalla. Gas turbine configuration for improving the performance of combined cycle power plant. Procedia Engineering, 15:4216–4223, 2011. doi: 10.1016/j.proeng.2011.08.791.
[24] M.N. Khan and I. Tlili. New advancement of high performance for a combined cycle power plant: Thermodynamic analysis. Case Studies in Thermal Engineering. 12:166–175, 2018. doi: 10.1016/j.csite.2018.04.001.
[25] S.Y. Ebaid and Q.Z. Al-hamdan. Thermodynamic analysis of different configurations of combined cycle power plants. Mechanical Engineering Research. 5(2):89–113, 2015. doi: 10.5539/mer.v5n2p89.
[26] R. Teflissi and A. Ataei. Effect of temperature and gas flow on the efficiency of an air bottoming cycle. Journal of Renewable and Sustainable Energy, 5(2):021409, 2013. doi: 10.1063/1.4798486.
[27] A.A. Bazmi, G. Zahedi, and H. Hashim. Design of decentralized biopower generation and distribution system for developing countries. Journal of Cleaner Production, 86:209–220, 2015. doi: 10.1016/j.jclepro.2014.08.084.
[28] A.I. Chatzimouratidis and P.A. Pilavachi. Decision support systems for power plants impact on the living standard. Energy Conversion and Management, 64:182–198, 2012. doi: 10.1016/j.enconman.2012.05.006.
[29] T.K. Ibrahim, F. Basrawi, O.I. Awad, A.N. Abdullah, G. Najafi, R. Mamat, and F.Y. Hagos. Thermal performance of gas turbine power plant based on exergy analysis. Applied Thermal Engineering, 115:977–985, 2017. doi: 10.1016/j.applthermaleng.2017.01.032.
[30] M. Ghazikhani, I. Khazaee, and E. Abdekhodaie. Exergy analysis of gas turbine with air bottoming cycle. Energy, 72:599–607, 2014. doi: 10.1016/j.energy.2014.05.085.
[31] M.N. Khan, I. Tlili, and W.A. Khan. thermodynamic optimization of new combined gas/steam power cycles with HRSG and heat exchanger. Arabian Journal for Science and Engineering, 42:4547–4558, 2017. doi: 10.1007/s13369-017-2549-4.
[32] N. Abdelhafidi, İ.H. Yılmaz, and N.E.I. Bachari. An innovative dynamic model for an integrated solar combined cycle power plant under off-design conditions. Energy Conversion and Management, 220:113066, 2020. doi: 10.1016/j.enconman.2020.113066.
[33] T.K. Ibrahim, M.K. Mohammed, O.I. Awad, M.M. Rahman, G. Najafi, F. Basrawi, A.N. Abd Alla, and R. Mamat. The optimum performance of the combined cycle power plant: A comprehensive review. Renewable and Sustainable Energy Reviews, 79:459–474, 2017. doi: 10.1016/j.rser.2017.05.060.
[34] M.N. Khan. Energy and exergy analyses of regenerative gas turbine air-bottoming combined cycle: optimum performance. Arabian Journal for Science and Engineering, 45:5895–5905, 2020. doi: 10.1007/s13369-020-04600-9.
[35] A.M. Alklaibi, M.N. Khan, and W.A. Khan. Thermodynamic analysis of gas turbine with air bottoming cycle. Energy, 107:603–611, 2016. doi: 10.1016/j.energy.2016.04.055.
[36] M. Ghazikhani, M. Passandideh-Fard, and M. Mousavi. Two new high-performance cycles for gas turbine with air bottoming. Energy, 36(1):294–304, 2011. doi: 10.1016/j.energy.2010.10.040.
[37] M.N. Khan and I. Tlili. Innovative thermodynamic parametric investigation of gas and steam bottoming cycles with heat exchanger and heat recovery steam generator: Energy and exergy analysis. Energy Reports, 4:497–506, 2018. doi: 10.1016/j.egyr.2018.07.007.
[38] M.N. Khan and I. Tlili. Performance enhancement of a combined cycle using heat exchanger bypass control: A thermodynamic investigation. Journal of Cleaner Production, 192:443–452, 2018. doi: 10.1016/j.jclepro.2018.04.272.
[39] M. Korobitsyn. Industrial applications of the air bottoming cycle. Energy Conversion and Management, 43(9-12):1311–1322, 2002. doi: 10.1016/S0196-8904(02)00017-1.
[40] T.K. Ibrahim and M.M. Rahman. optimum performance improvements of the combined cycle based on an intercooler–reheated gas turbine. Journal of Energy Resources Technology, 137(6):061601, 2015. doi: 10.1115/1.4030447.
Go to article

Authors and Affiliations

Michał Ciszewski
Michał Wacławski
Tomasz Buratowski
Mariusz Giergiel
Krzysztof Kurc

This page uses 'cookies'. Learn more