Sesija: Eksploatacioni problemi termo/hidro/vetro i drugih elektrana

Razvoj i primena tehničkih dijagnostičkih metoda i opreme za praćenje i vođenje procesa; unapređenje opreme sa aspekta procesa koji se u njima odvijaju; savremena organizacija proizvodnje, metode i sredstva održavanja opreme.

Radovi odabrani za sesiju Konferencije pod nazivom: Eksploatacioni problemi termo/hidro/vetro i drugih elektrana

nazad na Sesije

• EFFECTS OF THE AGRICULTURAL AND FOREST BIOMASS CHARACTERISTICS FOR THE PURPOSES OF ENERGY APPLICATIONS

  Branislav Repić (University of Belgrade, Vinca Institute of Nuclear Sciences, Laboratory for Thermal Engineering and Energy, P.O. Box 522, 11001 Belgrade, Serbia) Ana Marinković (University of Belgrade, Vinca Institute of Nuclear Sciences, Laboratory for Thermal Engineering and Energy, P.O. Box 522, 11001 Belgrade, Serbia) Dejan Djurović (University of Belgrade, Vinca Institute of Nuclear Sciences, Laboratory for Thermal Engineering and Energy, P.O. Box 522, 11001 Belgrade, Serbia) Vuk Spasojević (University of Belgrade, Vinca Institute of Nuclear Sciences, Laboratory for Thermal Engineering and Energy, P.O. Box 522, 11001 Belgrade, Serbia) Aleksandar Erić (University of Belgrade, Vinca Institute of Nuclear Sciences, Laboratory for Thermal Engineering and Energy, P.O. Box 522, 11001 Belgrade, Serbia)

  Sesija

  Eksploatacioni problemi termo/hidro/vetro i drugih elektrana

  Poslao

  Branislav

  Abstrakt

  Biomass is the most important renewable energy source in Serbia. The production of heat and electricity using biomass can be very important. Biomass is a very high quality fuel, but with specific characteristics that make it different from fossil fuels and influence different ways of its use. In this paper has been analyzed and compared characteristics of different types of agricultural and forest biomass for the purpose of a sustainable source of energy. The analysis used the results of numerous ultimate, proximate and chemical analyses of different types of biomass. All the characteristics are determined in accordance with the relevant standards. Based on obtained results different technologies for combustion of agricultural and forest biomass has been analyzed. In addition to that, it was analyzed various aspects of practical application of biomass through references of solving the basic problems that occurs during combustion of agricultural and forest biomass. Special emphasis in this analysis has been focused on agricultural biomass, whose practical application requires knowledge of the specific characteristics of the ashes that create big problems in the practical operation of the biomass plant. Obtained results have their practical application in concrete plants design with selected type of biomass.
• TO THE QUESTION ABOUT THERMAL EFFICIENCY OF DOUBLE-HEIGHT SCREENS IN LIQUID FUEL HOT-WATER BOILERS UP TO 3.15 MW CAPACITY

  R. K. Orumbaev (Almaty University of Power Engineering and Telecommunication, Almaty, Kazakhstan) A. A. Kibarin (Almaty University of Power Engineering and Telecommunication, Almaty, Kazakhstan) Sh. R. Orumbaeva (Almaty University of Power Engineering and Telecommunication, Almaty, Kazakhstan) M. S. Korobkov (Almaty University of Power Engineering and Telecommunication, Almaty, Kazakhstan) T. V. Khodanova (Almaty University of Power Engineering and Telecommunication, Almaty, Kazakhstan) A.F. Volkov (LLP “Kazkotloservis”, Almaty, Kazakhstan)

  Sesija

  Eksploatacioni problemi termo/hidro/vetro i drugih elektrana

  Poslao

  korobkovmax

  Abstrakt

  In this paper are given the results of thermal tests of hot-water boilers with heat capacity up to 3.15 MW. Performed the evaluation of thermal efficiency of double-height screens made in form of coaxial cylinders by the combustion of diesel fuel. According to the growing needs of the Republic of Kazakhstan in effective autonomous heat sources arose the need to expand the range of manufactured hot-water boilers. Specialists from LLP “Kazkotloservis” developed the cylindrical design of the hot-water boiler “KKS-KVa” with coaxial double-height combustion chamber made in order to maximize usage of the heating surfaces of the furnace and to increase heat transfer from the luminous flame. For intensification of convective heat transfer in the new KVa series boiler in all longitudinal flame tubes installed emitters - twisted steel inserts with a large winding angle (45°). To conduct acceptance of the factory were prepared thermotechnical tests and scientific research on the test bench that allows determining the thermotechnical, economic and environmental performance of KVa boilers with heat output of 0.4 to 3.15 MW. Steel hot-water KVa boilers are made in cylindrical form with an arrangement of flame tubes in three concentric rows above the coaxially double-height furnace screens. The external shell of all KVa boilers is a cylindrical barrel sheet. The tube plates with the equal diameters are welded to the barrel sheet from two sides; they form the body of the boiler that is filled with water. Below the longitudinal axis of the barrel sheet with an offset of 150 mm to 350 mm (depending on thermal capacity of the KVa boiler) is installed longitudinal axis of coaxial the combustion chamber. Around the combustion chamber from the outside is situated the body of the furnace barrel sheet. Inside of each of the flame tubes are mounted longitudinal coiled steel strips with a twist angle up to 45°. Tape inserts perform the function of twisting the longitudinal gas flow in the pipe and direct the flow to the wall, and simultaneously perform functions of heat emitters by increasing convective heat transfer. The hot-water boilers of KVa-Series has combustion chamber (combuster) performed in the way that both of its walls (inner wall and outer wall) from both sides in conjunction with inner wall work as faces, which receive radiant component of energy from expanded flame during the process of diesel fuel combustion. Besides, the main portion of that radiant energy is received by inner wall of the combustion chamber and then, after the turn of expanded flame and getting into the ring-shaped channel the radiant part of the energy is received by outer wall of combustion chamber and inner wall of the combustor. The main constructive feature of the hot-water boilers of KVa-series which were tested – is the expanded luminous flame with division and allocation of the second part of the flame into a coaxial clearance between inner wall of combustion chamber and combustor shell. It provides complete burn out of liquid fuel.
• SYSTEM FOR CALCULATION OF STEAM TURBINE PART LOAD BEHAVIOUR

  Miloš Popović (University of Belgrade-Faculty of Mechanical Engineering, Belgrade) Milan Banjac (University of Belgrade-Faculty of Mechanical Engineering, Belgrade) Milan V. Petrović (University of Belgrade-Faculty of Mechanical Engineering, Belgrade)

  Sesija

  Eksploatacioni problemi termo/hidro/vetro i drugih elektrana

  Poslao

  mpetrovic1

  Abstrakt

  Steam turbines operation at partial loads are increasingly requested taking into account the increase in share of unpredictable renewable energy sources, especially wind and solar energy, in power systems. Also, in case of combined heat and power production (CHP) during large steam extraction for hot water heating, LP turbine operates with very reduced flow, that is, at the far off conditions. In this paper, a system for the calculation of the behavior of steam turbine at different operating conditions is presented. Applying of the developed model it is possible, based on a relatively small number of geometric data, to determine the most important operating characteristics of turbine. The paper presents the results of calculations for a low pressure 165 MW turbine. The results can be applied during the design phase to optimize the design of the turbine as well as in the exploitation as important data for part and low load operation of the power plant.
• REALIZATION OF A POWER SYSTEM STABILIZER IN THE FIXED-POINT ARITHMETIC

  Slavko Veinović*, Đorđe Stojić*, Milan Milinković*, Zoran Ćirić*, Zoran Božović** (University of Belgrade, Electrical Institute „Nikola Tesla“, Koste Glavinića 8a, Beograd* )

  Sesija

  Eksploatacioni problemi termo/hidro/vetro i drugih elektrana

  Poslao

  slavko.veinovic

  Abstrakt

  In this paper the realization of a single-channel conventional power system stabilizer (PSS) is presented, realized in the fixed-point arithmetic. The PSS represents a part of synchronous generator excitation controller, implemented by means of the same control platform used for the digital voltage controller DARP, produced by Electrical institute Nikola Tesla. The voltage regulator and PSS program code is implemented on the 16-bit digital signal processor, by means of the standard C programming language, to be tested by using of the simulation package Simulink. The PSS is tested by means of the standard four machine test bench model. The PSS algorithm implemented by using a fixed-point arithmetic is verified by comparing it with a floating-point arithmetic based generic PSS with the rotor speed used as the input signal. Also, in the paper the PSS parameter tuning procedure is presented. By using the two differential compensators the control system phase characteristics is tuned in the frequency range from 0.2 to 3 Hz. In this way, the dumping of the slowly varying system modes is increased. The small-signal PSS responses are simulated, and the system stability is examined for typical power system disturbances. The results justify use of the fixed-point arithmetic based microprocessor in power system stabilization.
• BARRIERS TO CHEMICAL LOOPING COMBUSTION (CLC) POWER PLANTS

  Prof. E. J. Anthony (Carbon Systems Engineering, Energy & Power Engineering Division,School of Engineering, Cranfield University Cranfield, England, UK)

  Sesija

  Eksploatacioni problemi termo/hidro/vetro i drugih elektrana

  Poslao

  b.j.anthony

  Abstrakt

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• OPTIMIZATION OF THE GUYED MAST EXPOSED TO WIND ACTION

  Milada Pezo (University of Belgrade, Vinca Institute of Nuclear Science, Laboratory for Thermal and Energy Research, P. O. Box 522, 11000 Belgrade, Serbia) Vukman Bakić (University of Belgrade, Vinca Institute of Nuclear Science, Laboratory for Thermal and Energy Research, P. O. Box 522, 11000 Belgrade, Serbia) Lato Pezo (University of Belgrade, Institute of General and Physical Chemistry, Studentski Trg 12-16, 11000 Belgrade, Serbia)

  Sesija

  Eksploatacioni problemi termo/hidro/vetro i drugih elektrana

  Poslao

  milada

  Abstrakt

  This paper presents the optimization of the geometrical parameters of the guyed mast exposed to wind loading. The optimization method used for this purpose is called the standard score analysis. The investigated tower is a 79 m tall guyed mast with four levels of guys, consisting of standard beam elements. The European standards EN 1993-3-1:2006 and EN 1993-1-6:2007 already give some information about the masts structure, definition and guidelines for internal forces, moments, natural frequencies, maximal displacement determination, etc. The optimization is performed for the dimensions of all mast elements, attachment points of the guys, the distances of the guys’ foundations from the mast, etc. The height of the mast, geometrical in-plan and bracing schemes of the mast, wind loading and material data are not variable. The optimization should ensure the minimal mast weight, minimal displacement of the top of the mast and minimal values of stress.
• COMMINUTION OF SOLID FUEL IN FLUIDIZED BED

  Milijana Paprika (University of Belgrade, Vinča Institute of Nuclear Sciences, Laboratory of Thermal Engineering and Energy, Belgrade, Serbia) Stevan Nemoda (University of Belgrade, Vinča Institute of Nuclear Sciences, Laboratory of Thermal Engineering and Energy, Belgrade, Serbia) Milica Mladenović (University of Belgrade, Vinča Institute of Nuclear Sciences, Laboratory of Thermal Engineering and Energy, Belgrade, Serbia) Branislav Repić (University of Belgrade, Vinča Institute of Nuclear Sciences, Laboratory of Thermal Engineering and Energy, Belgrade, Serbia) Goran Živković (University of Belgrade, Vinča Institute of Nuclear Sciences, Laboratory of Thermal Engineering and Energy, Belgrade, Serbia)

  Sesija

  Eksploatacioni problemi termo/hidro/vetro i drugih elektrana

  Poslao

  milijana.paprika

  Abstrakt

  Comprehension of the comminution processes of solid fuels in fluidized bed (FB) over a range of fuel types, sizes and FB conditions is useful, sometimes even essential, in understanding and optimizing the practical coal combustion and creating credible combustion models. These processes are important concomitants of combustion and, therefore, influence behavior of the fluidized bed inventory, char and ash formation, and emission of pollutants. An analysis of comminution processes of different fuels under FB conditions were carried out and some estimation of size distributions are given. Also, an analysis of the fragmentation processes for different types of fuels are given.