- Type of paper
: Paper in journal
Title: The mathematical model of the steam generator combustion
chamber
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
Journal: Automatika
Number: 3
ISSN: 0005-1144
Volume: 33
Year: 1992
Pages: from 93 to 97
Number of references: 10
Language: engleski
Keywords: mathematical modeling, steam generator furnace
- Type of paper
: Paper in journal
Title: Prediction of once-through boiler steady states and
dynamics in sliding pressure regime by simulation
- Authors:
- Šerman, Nikola (46501.00000)
Journal: Automatika
Number: 3
ISSN: 0005-1144
Volume: 33
Year: 1992
Pages: from 99 to 104
Number of references: 4
Language: engleski
- Type of paper
: Paper in journal
Title: Influence of spatial discretization on the results of the
distributed parameters plant control simulation
- Authors:
- Šerman, Nikola (46501.00000)
Journal: Automatika
Number: 1
ISSN: 0005-1144
Volume: 34
Year: 1993
Pages: from 67 to 72
Number of references: 5
Language: engleski
- Type of paper
: Paper in journal
Title: Flow velocities computation inside a complexly shaped
furnace with boundary condition approximation
- Authors:
- Martinis, Vinko (29004.00000)
- Novko, Igor (184335.00000)
Journal: Automatika
Number: 1
ISSN: 0005-1144
Volume: 34
Year: 1993
Pages: from 73 to 76
Number of references: 2
Language: hrvatski
Summary: The application of nonperpendicular nets usual computing
numerical problems with two-dimensional domain in three-dimensional cases
leads to serious difficulties when transferring real nets into numerically
perpendicular ones. In this paper a perpendicular net relevant to furnace
volume is retained so that differential equations discretisation is
standard. As nodal points do not always fall into domain's boundary the
approximation of boundary conditions is carried out at domain's nodal
points that are closest to the boundary. That way a three-dimensional
problem does not really differ from a two-dimensional problem. Such an
approach is applicable with other methods od discretisation and equation
system computation. In this paper a numerical solution of mathematicam
model of a complexly shaped furnace found by numerical compression method
is shown.
- Type of paper
: Paper in journal
Title: Heat transfer calculation of the furnace with a
two-dimensional mathematical model
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
Journal: Zbornik radova Fakulteta strojarstva i brodogradnje
Sveučilišta u Zagrebu
ISSN: 0350-3097
Volume: 16
Year: 1992
Pages: from 197 to 204
Number of references: 6
Language: hrvatski
Summary: Using a two-dimensional mathematical model, the calculation
of an oil fired 330 t/h steam generator combustion chamber is carried out.
The calculation gives gas velocity, fuel and oxygen concentration and
temperature fields inside the furnace, as well as the distribution of heat
fluxes along the furnace walls. The simulation of the furnace behavior
under steady-state condition is performed in the range of 50-100 % load.
The results are very favorably compared with the data supplied by the steam
generator manufacturer.
- Type of paper
: Paper in journal
Title: Aplication of multigrid correction method on flow
calculation in a steam generator
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
Journal: Zbornik radova Fakulteta strojarstva i brodogradnje
Sveučilišta u Zagrebu
ISSN: 0350-3097
Volume: 17
Year: 1993
Pages: from 147 to 154
Number of references: 6
Language: hrvatski
Summary: In this paper the rate of convergence of the multigrid
method with additive corrections when solving the two-dimensional
mathematical model of the steam generator combustion chamber is analyzed.
The mathematical model is represented by the system of strongly nonlinear
partial differential equations. The solution of the mathematical model is
obtained by the global iterative procedure. In one global iteration the
system of equations of one variable is solved by applying line Gauss-Seidel
iterative procedure. A great improvement in convergence is achieved by
applying the multigrid method with additive corrections in solving
mathematical model of the combustion chamber.
- Type of paper
: Paper in journal
Title: Solar thermal power plants on the way to commercialization
- Authors:
- Duić, Neven (179672.00000)
Journal: Sunčeva energija
Number: 2
ISSN: 0351-2797
Volume: 14
Year: 1993
Pages: from 61 to 68
Number of references: 8
Language: hrvatski
Summary: The paper analyses development of solar thermal power
plants during last ten years. The question of commercial utilization of
such plants is highlighted. Several most important types of such plants are
discussed: central receiver system, parabolic through system, solar pond
system all the way to the modular solar power plants for isolated
consumers. Different solar thermal systems are compared to the conventional
thermal power plants by means of cost analyses.
Keywords: solar thermal, central receiver, parabolic through, solar pond
- Type of paper
: Paper in proceedings
Title: Examination of once through boiler control strategy by
simulation
- Authors:
- Šerman, Nikola (46501.00000)
- Mavračić, Krešimir
- Editors
- El Moudni, A.
- Borne, P
- Tzafestas, S.G.
Proceedings title: Proceedings of IMACS MCTS 91
Language: engleski
Place: Lille, Francuska
Year: 1991
ISBN/ISSN: 29502908-1-7
Pages: from 349 to 354
Meeting: IMACS IFAC Symposium on Modeling and Control of Technological Systems
Held: from 05/07/91 to 05/10/91
- Type of paper
: Paper in proceedings
Title: Contribution to investigation of variable area flowmeter
- Authors:
- Bogdan, Željko (4210.00000)
- Editors
- Galaso, Ivan
Proceedings title: Proceedings of INTERKLIMA 91
Language: engleski
Place: Zagreb
Year: 1991
Pages: from 233 to 239
Meeting: INTERKLIMA 91, 11th International Symposium of Heating, Refrigareting and Air Conditioning
Held: from 06/12/91 to 06/13/91
- Type of paper
: Paper in proceedings
Title: The mathematical model of a steam accumulator
- Authors:
- Duić, Neven (179672.00000)
- Editors
- Galaso, Ivan
Proceedings title: Proceedings of INTERKLIMA 91
Language: engleski
Place: Zagreb
Year: 1991
Pages: from 249 to 256
Meeting: INTERKLIMA 91, 11th International Symposium of Heating, Refrigareting and Air Conditioning
Held: from 06/12/91 to 06/13/91
Other: Zbornik radova nema ISBN.
- Type of paper
: Paper in proceedings
Title: Prediction of once through boiler steady states and
dynamics in sliding pressure regime by simulation
- Authors:
- Šerman, Nikola (46501.00000)
- Editors
- Kecman, Vojislav
Proceedings title: Zbornik radova KoREMA 37
Language: engleski
Place: Zagreb
Year: 1992
ISBN/ISSN: 86-81571-11-7
Pages: from 85 to 89
Meeting: 37. Međunarodni godišnji skup KoREMA
Held: from 04/26/92 to 04/29/92
- Type of paper
: Paper in proceedings
Title: The mathematical model of the steam generator combustion
chamber
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
- Editors
- Kecman, Vojislav
Proceedings title: Zbornik radova KoREMA 37
Language: engleski
Place: Zagreb
Year: 1992
ISBN/ISSN: 86-81571-11-7
Pages: from 77 to 80
Meeting: 37. Međunarodni godišnji skup KoREMA
Held: from 04/26/92 to 04/29/92
Keywords: mathematical modeling, steam generator furnace
- Type of paper
: Paper in proceedings
Title: The mathematical model of the production of carbon dioxide
and sulphur dioxide in the steam generator furnace
- Authors:
- Duić, Neven (179672.00000)
- Bogdan, Željko (4210.00000)
- Editors
- Franković, Bernard
Proceedings title: Zbornik radova XIII. Međunarodnog kongresa Energija i zaštita čovjekove okoline
Language: hrvatski
Place: Opatija
Year: 1992
ISBN/ISSN: 86-81601-01-8
Pages: from 255 to 262
Meeting: XIII. Međunarodni kongres Energija i zaštita čovjekove okoline
Held: from 10/28/92 to 10/30/92
Summary: The two-dimensional mathematical model of processes inside
the furnace is described with special attention given to the production of
carbon dioxide and sulfur dioxide. The model consists differential
equations of continuity, impulse, enthalpy and transport of chemical
species, which are discretized by control volume scheme. Two optional
models are applied: oil firing and natural gas firing. The source terms in
the transport equations of species are modeled by the Arrhenius law of
reaction rate. The resulting distributions of combustion products for oil
model of combustion is shown and compared with the experimental results.
Keywords: mathematical model, furnace
- Type of paper
: Paper in proceedings
Title: Numerical computation of threedimensional flow models
inside a furnace by the PISO method
- Authors:
- Martinis, Vinko (29004.00000)
- Editors
- Kecman, Vojislav
Proceedings title: Zbornik radova KoREMA 37
Language: hrvatski
Place: Zagreb
Year: 1992
ISBN/ISSN: 86-81571-11-7
Pages: from 81 to 84
Meeting: 37. Međunarodni godišnji skup KoREMA
Held: from 04/26/92 to 04/29/92
Summary: Computing furnace temperature field is divided into thermal
and fluid flow parts. This enables separate study of fluid flows with a
quick transient process. In this paper the numerical computation of
steady-state flows by unstationary threedimensional nonlinear fluid flow
model is shown. The stability and the second order accurancy in spatial
coordinates are achieved by implicit discretisation of time derivative.
Moreover, the quick transient process with the use of PISO method for
sloving discretised equations significantly reduces calculation scope.
- Type of paper
: Paper in proceedings
Title: Influence of spatial discretiyation on the results of the
distributed parameters plant control
- Authors:
- Šerman, Nikola (46501.00000)
- Editors
- Novaković, Branko
Proceedings title: Zbornik radova KoREMA 38
Language: engleski
Place: Zagreb
Year: 1993
ISBN/ISSN: 953-6037-00-9
Pages: from 471 to 475
Meeting: 38. Međunarodni godišnji skup KoREMA
Held: from 04/26/93 to 04/28/93
- Type of paper
: Paper in proceedings
Title: The three-dimensional mathematical model of the horizontal
furnace
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
- Editors
- Kalpić, Damir
Proceedings title: Zbornik radova KoREMA 38
Language: engleski
Place: Zagreb
Year: 1993
ISBN/ISSN: 953-6037-00-9
Pages: from 584 to 587
Meeting: 38. Međunarodni godišnji skup KoREMA
Held: from 04/26/93 to 04/28/93
Summary: International Flame Research Foundation experimental
furnace in IJmuiden (Netherlands) is modeled by the three-dimensional
mathematical model, in order to check the results of simulation against the
measured ones. The furnace is horizontal with nearly square cross-section.
Holes for positioning of measuring equipment are placed on side walls. The
mathematical model of the furnace includes fluid flow processes with
recirculation of combustion products, combustion of oil, radiation heat
transfer as well as transport of fuel and combustion products through the
inside of the furnace. Calculated temperature field is compared to the
experimental data with satisfactory agreement.
- Type of paper
: Paper in proceedings
Title: Numerical simulation of air-flow in a heated room
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
- Editors
- Galaso, Ivan
Proceedings title: Proceedings of INTERKLIMA 93
Language: engleski
Place: Zagreb
Year: 1993
ISBN/ISSN: 953-6037-01-7
Pages: from 7 to 12
Meeting: INTERKLIMA 93, 12th International Symposium of Heating, Refrigerating and Air-conditioning
Held: from 06/09/93 to 06/11/93
Summary: In this paper the three-dimensional numerical simulation of
air-flow induced by heating body in a room is presented. The mathematical
model consists of partial differential equations of mass conservation and
transport of momentum and energy. Evaluation of numerical model is based on
control volume approach. The mathematical model is tested against
analytical solution which exists for cavity with heated and cooled vertical
walls with very good agreement. Demonstration calculation is also presented
for a room heated by a radiator and cooled through windows and the walls.
Results are presented in the form of cross-sectional views of velocity and
temperature fields.
- Type of paper
: Paper in proceedings
Title: Three-dimensional simulation of the combustion process in
an oil-fired furnace
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
- Editors
- Čerić, Vlatko
- Hljuz-Dobrić, Vesna
Proceedings title: Proceedings of ITI 93
Language: engleski
Place: Zagreb
Year: 1993
ISBN/ISSN: 1330-1012
Pages: from 351 to 356
Meeting: 15th International Conference on Information Technology Interfaces
Held: from 06/15/93 to 06/18/93
Summary: In this paper the three-dimensional numerical simulation of
the fuel combustion, flue gas flow and radiation heat transfer in an oil
fired furnace is presented. The mathematical model of oil-combustion is
fully empirical, based on experimental data. The flue gas flow model is
described by partial differential equations of mass, momentum and energy
conservation. The simplification of zone method is used for radiation heat
transfer modelling. Evaluation of numerical discretization is based on the
control volume approach. Sensitivity analysis of the grid refinement in the
range of 5000 to 17500 control volumes is carried out.
- Type of paper
: Paper in proceedings
Title: Flow velocities computation inside a complexly shaped
furnace with boundary condition approximation
- Authors:
- Martinis, Vinko (29004.00000)
- Novko, Igor (184335.00000)
- Editors
- Kalpić, Damir
Proceedings title: Zbornik radova KoREMA 38
Language: hrvatski
Place: Zagreb
Year: 1993
ISBN/ISSN: 953-6037-00-9
Pages: from 297 to 303
Meeting: 38. Međunarodni godišnji skup KoREMA
Held: from 04/26/93 to 04/28/93
Summary: The application of nonperpendicular nets usual computing
numerical problems with two-dimensional domain in three-dimensional cases
leads to serious difficulties when transferring real nets into numerically
perpendicular ones. In this paper a perpendicular net relevant to furnace
volume is retained so that differential equations discretisation is
standard. As nodal points do not always fall into domain's boundary the
approximation of boundary conditions is carried out at domain's nodal
points that are closest to the boundary. That way a three-dimensional
problem does not really differ from a two-dimensional problem. Such an
approach is applicable with other methods od discretisation and equation
system computation. In this paper a numerical solution of mathematicam
model of a complexly shaped furnace found by numerical compression method
is shown.
- Type of paper
: Paper in proceedings
Title: Description of two-phase flow test loop with forced
circulation
- Authors:
- Firak, Mihajlo (12003.00000)
- Editors
- Boršić, Mladen
- Mahović, Sanjin
Proceedings title: Zbornik radova KoREMA 38
Language: hrvatski
Place: Zagreb
Year: 1993
ISBN/ISSN: 953-6037-00-9
Pages: from 297 to 303
Meeting: 38. Međunarodni godišnji skup KoREMA
Held: from 04/26/93 to 04/28/93
Summary: An experimental set-up for research of thermohydraulical
phenomena with diabatic forced flow of one component two-phase water flow
has been built at Thermal Power Plants Laboratory of the Faculty of
Mechanical Engineering and Naval Architecture, Zagreb. Basically, this loop
represents monotube steam generator with forced flow (0.5 - 4)x10-2 kg/s,
at working pressure between 20 and 200 bar and superheated steam
temperature up to 550 řC. Preheater and evaporating tube heating (and
consequently medium heating) is done electrically by conduction of electric
power through the wall of the tube. Maximum electric power of the test loop
is 100 kW. By properly selected electric parameters (i.e. current and
voltage), tube materials, tube dimensions and process parameters, (flow,
pressure and temperature), it is possible to ensure various two-phase flow
thermohydraulical phenomena. Incorporated sensors of electric and process
parameters, connected together with computer aided data acquisition and
processing system allow monitoring and analysis of the experiments. This
paper presents basic components of the test loop, and as an illustration of
its experimental abilities, a graphical presentation of certain system
transients during suffocation of output valve with steam.
Keywords: two-phase flow, experimental set-up, thermohydraulical phenomena
- Type of paper
: Paper in proceedings
Title: Protecting infuction turbine flowmeter from
elektromagnetic interference
- Authors:
- Firak, Mihajlo (12003.00000)
- Jakovljević, Žarko (171432.00000)
- Editors
- Boršić, Mladen
- Mahović, Sanjin
Proceedings title: Zbornik radova KoREMA 38
Language: hrvatski
Place: Zagreb
Year: 1993
ISBN/ISSN: 953-6037-00-9
Pages: from 321 to 327
Meeting: 38. Međunarodni godišnji skup KoREMA
Held: from 04/26/93 to 04/28/93
Summary: Induction turbine flowmeter for water is incorporated into
laboratory experimental set-up for researching thermohydraulic phenomena of
diabatic two-phase forced flow. After passing through the flowmeter, water
is heated in the monotube preheater by means of Joule's heat which is
developed in the tube wall. Three-phase transformer with maximal power of
63 kW has the output parameters 1500 A and 16 V max. Transformer, preheater
and connecting cables are all together very strong source of
electromagnetic field. This field induces parasitic alternating voltage in
the coil of induction turbine flowmeter which is superposed to the voltage
formed due to the certain flow. Resulting output voltage carries both
disturbance and information about flow, where disturbance can be stronger.
The paper presents simple experimental/analytical way for approximate
determination the strength of disturbation source alternating magnetic
field in a certain point of space. The results of shielding factor
experimental evaluation for six different shields, which protect induction
turbine flowmeter from electromagnetic interference, are also presented.
Keywords: protecting induction turbine flowmeter from electromagnetic interference
- Type of paper
: Paper in proceedings
Title: Computer-aided processing of measurement data collected on
two-phase flow test loop
- Authors:
- Jakovljević, Žarko (171432.00000)
- Firak, Mihajlo (12003.00000)
- Editors
- Čerić, Vlatko
- Hljuz-Dobrić, Vesna
Proceedings title: Proceedings of ITI 93
Language: engleski
Place: Zagreb
Year: 1993
ISBN/ISSN: 1330-1012
Pages: from 45 to 48
Meeting: 15th International Conference on Information Technology Interfaces
Held: from 06/15/93 to 06/18/93
Summary: An experimental two-phase flow test loop has been built at
Thermal Power Plants Laboratory of Faculty of Mechanical Engineering and
Naval Architecture, Zagreb. Short description of facility is given and its
role in educational process is explained. Measurement data collected on
this loop are processed with MATLAB software package. Description of
developed algorithms is given and advantages of their application for
educational purposes are stated.
Keywords: experimental facility, signal processing, MATLAB, education
- Type of paper
: Paper in proceedings
Title: Measuring velocity and temparature fields in industrial
and experimental furnaces
- Authors:
- Slavica, Željko (146131.00000)
- Editors
- Boršić, Mladen
- Mahović, Sanjin
Proceedings title: Zbornik radova KoREMA 38
Language: hrvatski
Place: Zagreb
Year: 1993
ISBN/ISSN: 953-6037-00-9
Pages: from 432 to 436
Meeting: 38. Međunarodni godišnji skup KoREMA
Held: from 04/26/93 to 04/28/93
Summary: The review of papers published during last 30 years is
presented covering measurement of velocity and temperature fields in
furnaces. Difference is made between measurements on industrial steam
generator furnaces and measurements on experimental furnace models in
laboratory conditions. Measuring equipment used in experiments is
specified, and problems that showed up with some parts of equipment during
measurement are also stated.
- Type of paper
: Paper in proceedings
Title: Mathematical model of the gas-fired furnace
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
Proceedings title: II. kolokvij Modeliranje u znanosti, tehnici i društvu, CROSS 92
Language: hrvatski
Place: Zagreb
Year: 1992
Meeting: II. kolokvij Modeliranje u znanosti, tehnici i društvu, CROSS 92
Held: from 12/11/92 to 12/11/92
Other: Zbornik je u tisku.
- Type of paper
: Paper in proceedings
Title: Water level control in the high pressure feedwater
preheaters of the utility power block
- Authors:
- Šerman, Nikola (46501.00000)
- Editors
- Štambuk-Boršić, Neda
Proceedings title: Zbornik radova KoREMA 39
Language: hrvatski
Place: Zagreb
Year: 1994
ISBN/ISSN: 953-6037-02-5
Pages: from 315 to 318
Meeting: 39. Međunarodni godišnji skup KoREMA
Held: from 04/25/94 to 04/27/94
Summary: Water level control strategy for the high-pressure feed
water preheaters of the 320 MW utility power block is proposed. By
proposing a new control system design in order to overcome functional
shortcomings of the existing local controllers, the particularities of the
regenerative feed water preheating system of the plant under consideration
have been respected. The proposed control system is expected to ensure
fully automatic water level control under all operational conditions of the
H.P. preheater cascade. The basic functional characteristics of the partial
technical solutions have been examined by use of simplified preheater
models. Quantitative estimation of the achievable control quality within
the preheater cascade under different operational conditions was performed
by simulation of the thermohydraulic model coupled with the control system
model.
- Type of paper
: Paper in proceedings
Title: Modeling and simulation of 320 MW thermal power block
feedwater heating system
- Authors:
- Lončar, Dražen (197152.00000)
- Šerman, Nikola (46501.00000)
- Editors
- Štambuk-Boršić, Neda
Proceedings title: Zbornik radova KoREMA 39
Language: hrvatski
Place: Zagreb
Year: 1994
ISBN/ISSN: 953-6037-02-5
Pages: from 264 to 268
Meeting: 39. Međunarodni godišnji skup KoREMA
Held: from 04/25/94 to 04/27/94
Summary: The mathematical model of the thermohydraulic processes in
the line of feedwater heaters has been developed . The control volume
approach and the implicit time domain discretization have been used to find
model's solution in each time step. Thus the system of differential
equations has been reduced to a system of nonlinear algebraic equations and
solved by the numerical procedure based on Newton-Raphson's method. The
influence of the different operational states on condensate flows has been
estimated by simulation. The simulation's results have been used for
verification of the proposed control system design.
- Type of paper
: Paper in proceedings
Title: Open flow boundary conditions at furnace exit in flow
computation
- Authors:
- Martinis, Vinko (29004.00000)
- Slavica, Željko (146131.00000)
- Editors
- Kalpić, Damir
Proceedings title: Zbornik radova KoREMA 39
Language: hrvatski
Place: Zagreb
Year: 1994
ISBN/ISSN: 953-6037-02-5
Pages: from 455 to 459
Meeting: 39. Međunarodni godišnji skup KoREMA
Held: from 04/25/94 to 04/27/94
Summary: Since flow velocities at industrial furnace exit are
unknown, it is difficult to define outflow boudary conditions in numerical
computation of partial differential equations governing fluid flow. In the
present paper the open flow boundary conditions are determined with a
relatively small extension of domain in the direction of outflow. The flow
equations are discretized by the finite-difference method, and the system
of equations is solved using the PISO method (Pressure-Implicit with
Splitting of Operators). The estimation of required domain extension is
given in order to determinate approximate fluid flow velocities at furnace
exit.
- Type of paper
: Paper in proceedings
Title: Simulation of oil heater control loop dynamics
- Authors:
- Lončar, Dražen (197152.00000)
- Editors
- Čerić, Vlatko
- Hljuz-Dobrić, Vesna
Proceedings title: Proceedings of ITI 93
Language: engleski
Place: Zagreb
Year: 1993
ISBN/ISSN: 1330-1012
Pages: from 61 to 64
Meeting: 15th International Conference on Information Technology Interfaces
Held: from 06/15/93 to 06/18/93
Summary: The paper deals with an educational demo-example, based on
the real-life control problem - the problem of the fuel temperature
control, commonly appearing in oil-fired thermal power blocks. Mathematical
model of the oil-heater has been developed and implemented in MATLAB1 in
order to be used as an object in illustrations of the simulation technique
itself and for further control-related investigations performed by
students. The model of the oil heater is briefly decsribed and some
simulation results are presented.
Keywords: modeling, simulation, MATLAB, education
- Type of paper
: Paper in proceedings
Title: Mathematical modelling and simulation of the 320MW thermal
power block
- Authors:
- Bogdan, Željko (4210.00000)
- Editors
- Štambuk-Boršić, Neda
Proceedings title: Zbornik radova KoREMA 39
Language: hrvatski
Place: Zagreb
Year: 1994
ISBN/ISSN: 953-6037-02-5
Pages: from 380 to 383
Meeting: 39. Međunarodni godišnji skup KoREMA
Held: from 04/25/94 to 04/27/94
Summary: In this paper the mathematical model which describes
thermodynamic behavior of the conventional thermal power plant for
electricity generation is presented. The mathematical model consists of the
three main parts: the steam generator model, the turbine model and the
model of regenerative feedwater heaters. The steam generator thermodynamic
model is based on the "normative" method. The mathematical model is used
for simulation of steady-state operation of the thermal power plant Rijeka.
Performance of the thermal power plant influenced by lowering of steam
generator feedwater inlet temperature due to accident closing of high
pressure water heaters is simulated. Good agreement of temperature profiles
along water-steam and flue gas-air tracts as well as water and steam flow
rates with power plant measured data is achieved.
- Type of paper
: Paper in proceedings
Title: Modeling of the high-temperature dissociation of CO2 in
the steam generator furnace
- Authors:
- Duić, Neven (179672.00000)
- Bogdan, Željko (4210.00000)
- Editors
- Čerić, Vlatko
- Hljuz-Dobrić, Vesna
Proceedings title: Proceedings of ITI 94
Language: engleski
Place: Zagreb
Year: 1994
ISBN/ISSN: 1330-1012
Pages: from 265 to 270
Meeting: 16th International Conference on Information Technology Interfaces
Held: from 06/14/94 to 06/17/94
Summary: While simulating combustion and heat transfer processes in
the steam generator furnace by the three-dimensional mathematical model,
local temperature maximums considerably exceeded values obtained by
measurement. It is caused partially by applied model of combustion kinetics
and partially by the dissociation of three-atom flue gases. The CO2
dissociation influence becomes notable already at 1500C, which means it
influences the processes in the furnace. The CO2 dissociation is modeled by
the assumption of a local equilibrium. Since as one of the products of the
dissociation is CO, the transport equation of carbon monoxide is
introduced. Together with the fuel oxidation model, the entire combustion
model includes four differential transport equations for following chemical
species: fuel, O2, CO2 and CO. In the paper the influence of CO2
dissociation on the temperature field in the oil-fired steam generator
furnace is shown. The influence is significant in high-temperature regions
where perceptible decrease of maximal temperatures is observed.
Keywords: carbon dioxide dissociation, numerical simulation, steam generator furnace
- Type of paper
: Paper in proceedings
Title: Prediction of the thermal radiation heat transfer in a
furnace by Monte Carlo zone method
- Authors:
- Bogdan, Željko (4210.00000)
- Schneider, Daniel Rolph
- Duić, Neven (179672.00000)
- Editors
- Čerić, Vlatko
- Hljuz-Dobrić, Vesna
Proceedings title: Proceedings of ITI 94
Language: engleski
Place: Zagreb
Year: 1994
ISBN/ISSN: 1330-1012
Pages: from 253 to 258
Meeting: 16th International Conference on Information Technology Interfaces
Held: from 06/14/94 to 06/17/94
Summary: The mathematical model of radiation heat transfer based on
the Monte Carlo method is developed and tested on a simple case of
radiation in a cubical enclosure for which numerical solution is available.
Number of emitted energy bundles in a sample is varied in order to
establish its influence on the final solution. Different averaging
techniques are tried in an attempt of decreasing the magnitude of the
temperature fluctuations during iterations which are the consequence of the
stochastic nature of the method. Basically the same mathematical model with
the additional provision for fuel heat generation is used for calculating
radiation heat transfer in a steam generator furnace. Results are shown in
the form of distributions of heat flux densities and temperatures in the
furnace and on its walls.
Keywords: Monte Carlo method, radiation heat transfer, numerical simulation
- Type of paper
: Paper in proceedings
Title: Zone boiler furnace calculation
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
- Editors
- Galaso, Ivan
- Iljaš, Branko
- Jakšić, Smiljko
- Šimunović, Ante
- Švaić, Srećko
Proceedings title: Zbornik radova Energetska i procesna postrojenja
Language: hrvatski
Place: Hrašće
Year: 1994
Pages: from 165 to 169
Meeting: Energetska i procesna postrojenja
Held: from 05/25/94 to 05/27/94
Keywords: furnace, zone method, mathematical modeling
Other: Zbornik radova nema ISBN.
- Type of paper
: Paper in proceedings
Title: Leakage detection in power plant boiler
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
- Schneider, Daniel Rolph
- Šerman, Nikola (46501.00000)
- Afgan, Naim
- Editors
- Reis, Albino
Proceedings title: Proceedings of 3rd European Conference on Industrial Furnaces and Boilers
Language: engleski
Place: Lisabon, Portugal
Year: 1995
Meeting: 3rd European Conference on Industrial Furnaces and Boilers
Held: from 04/18/95 to 04/21/95
Summary: The paper deals with the feasibility of using the radiation
heat flux measurement as the diagnostic variable for the tube leakage
detection system. The mathematical model based on the Monte Carlo zone
method is used to investigate sensitivity of the radiative heat flux
changes due to the water leakage into the furnace. Control volume based
mathematical model is used to determine temperature, velocity and
concentration fields. Radiative properties are determined by the three gray
gases model. It was shown that the heat flux might be sufficiently
sensitive diagnostic variable to be used in on-line monitoring of the large
power plant boiler.
Keywords: boiler tube leakage, Monte Carlo method, numerical simulation, mathematical modeling, combustion chamber
Other: Zbornik nije numeriran i nema ISBN.
- Type of paper
: Paper in proceedings
Title: Tube leakage effect on radiation heat flux in boiler
- Authors:
- Duić, Neven (179672.00000)
- Bogdan, Željko (4210.00000)
- Schneider, Daniel Rolph
- Šerman, Nikola (46501.00000)
- Afgan, Naim
Language: engleski
Year: 1995
Meeting: ICHMT International Symposium on Radiative Heat Transfer
Held: from 08/14/95 to 08/18/95
Summary: Early diagnostics of tube leakage in a furnace would help
in preventing the failure by planning maintenance. In the vicinity of the
tube leakage the concentration of water vapor is increased and heat flux
density distribution on the furnace wall changed. The degree of change is
measure of the incident. The Monte Carlo zone method based mathematical
model was developed in order to enable that analysis. The three-dimensional
mathematical model describes steady-state behavior of the steam generator
furnace. It was shown that the radiative heat flux is sufficiently
sensitive to detect the water leakage into the furnace.
Keywords: boiler tube leakage detection, Monte Carlo method, combustion chamber
Other: Konačna verzija Zbornika radova u tisku. Preliminarna
verzija, zbornik sažetaka nema ISBN.
- Type of paper
: Paper in proceedings
Title: Examination of the water level control strategy for the
feed water preheaters of the 320 MW utility power blok by computer
simulation
- Authors:
- Šerman, Nikola (46501.00000)
- Lončar, Dražen (197152.00000)
- Editors
- Galaso, Ivan
- Iljaš, Branko
- Jakšić, Smiljko
- Šimunović, Ante
- Švaić, Srećko
Proceedings title: Zbornik radova Energetska i procesna postrojenja
Language: hrvatski
Place: Hrašće
Year: 1994
Pages: from 446 to 453
Meeting: Energetska i procesna postrojenja
Held: from 05/25/94 to 05/27/94
Summary: The new control system for the high pressure feed water
preheaters has been designed in order to overcome functional shortcomings
of the existing local controllers. The proposed control system is expected
to ensure fully automatic water level control under all operational
conditions. Quantitative estimation of the acheivable control quality
within the preheater cascade under different operational conditions was
performed by simulation of the termohydraulic model coupled with control
system model.
Keywords: feedwater preheaters, level control, simulation
Other: Zbornik radova nema ISBN.
- Type of paper
: Paper in proceedings
Title: Calculation of NOx production in a large steam generator
combustion chamber
- Authors:
- Bogdan, Željko (4210.00000)
- Editors
- Franković, Bernard
Proceedings title: Zbornik radova XIV. Međunarodnog kongresa Energija i zaštita okoliša
Language: engleski
Place: Opatija
Year: 1994
ISBN/ISSN: 953-96054-3-1
Pages: from 27 to 33
Meeting: XIV. Međunarodni kongres Energija i zaštita okoliša
Held: from 10/26/94 to 10/28/94
Summary: In this paper the mathematical model of steady state
thermodynamic processes inside a 1000 t/h steam generator is presented. It
is a lumped model based on the "normative" design method. In the combustion
chamber model the enhanced Zeldovich mechanism for thermal NO calculation
is incorporated. Calculation results of the temperature profiles along
water-vapor, flue gas and air tracts are successfully compared with
measurements data. Results of NOx calculations are shown graphically for
three different power plant loads.
Keywords: NOx production, mathematical modelling, steam generator
- Type of paper
: Paper in proceedings
Title: Steam generator design based on mathematical modelling
- Authors:
- Bogdan, Željko (4210.00000)
- Editors
- Kalpić, Damir
- Hljuz-Dobrić, Vesna
Proceedings title: Proceedings of ITI 95
Language: engleski
Place: Zagreb
Year: 1995
ISBN/ISSN: 1330-1012
Pages: from 419 to 424
Meeting: 17th International Conference on Information Technology Interfaces
Held: from 06/13/95 to 06/16/95
Summary: A mathematical model for the water-tube type of the steam
generator is developed. The model has provisions for different types of
heat exchange surfaces. Uniform inputs and outputs of the models of these
surfaces enable easy inclusion into the main model where the configuration
of steam generator is defined. The mathematical model is one-dimensional
with heat exchange surfaces being nods of the system. The model is used as
an auxiliary tool in upgrading design of the steam generator for fast steam
production.
- Type of paper
: Paper in proceedings
Title: Modeling of a solid fuel combustion chamber of a ramjet
using a multi-block domain decomposition technique
- Authors:
- Coelho, Pedro J.
- Duić, Neven (179672.00000)
- Lemos, C.
- Carvalho, Maria da Gra‡a
Language: engleski
Year: 1996
Meeting: 34th Aerospace Sciences Meeting
Held: from 01/15/96 to 01/18/96
Other: Rad je prihvaćen za objavljivanje.
- Type of paper
: M.A.
Title: Computer-aided experiment supervision and data acquiring
and processing on the experimental evaporator
Faculty: Fakultet strojarstva i brodogradnje Sveučilište u Zagrebu
Date of defense: 03/18/93
Language: hrvatski
Number of pages: 105
- Type of paper
: M.A.
Title: Three-dimensional mathematical model of the processes in
the steam generator furnace
Faculty: Fakultet strojarstva i brodogradnje Sveučilište u Zagrebu
Author: DUIĆ NEVEN
Date of defense: 07/14/93
Language: hrvatski
Number of pages: 121
- Type of paper
: Mentorship
Title: Computer-aided experiment supervision and data acquiring
and processing on the experimental evaporator
Faculty: Fakultet strojarstva i brodogradnje Sveučilište u Zagrebu
Mentor: ŠERMAN NIKOLA
Date of defense: 03/18/93
Number of pages: 105
Author: Jakovljević mr.sc. Žarko
Degree level: M.A.
Summary: In order to investigate thermohydraulical phenomena in
two-phase diabatic flow, a laboratory once-through evaporator with
electrically heated tube wall has been built. Subject of this work is
realization of computer-aided experiment supervision and computer-aided
data acquiring and processing by means of HP 9000/320 computer system and
HP 3852A Data Acquisition/Control Unit. Experimental loop and its
functioning have been described. Characteristics of measuring equipment and
computer system have been stated. Operating conditions supervision demands
and loop protection demands have been defined. Some basic theoretical
concepts needed for successful organizing of measurement data acquisition
have been presented (time-domain and frequency-domain description of
system parameters). Various possibilities of data acquiring and storing by
means of available computer system have been considered. Special software
has been designed for operating conditions supervision, loop protection and
data acquisition. Its structure has been described and explained in
details. Program's basic mode and special modes have been described, and
the role of each computer system component in accomplishing aforesaid tasks
has been explained. Basic theoretical concepts of signal processing have
been introduced, while problems related with choosing data processing
hardware and software have been mentioned. Various algorithms for data
processing have been developed and their application has been illustrated
on few chosen samples from experimental loop
Keywords: data acquisition, signal processing, software, MATLAB, HP 3852A, experimental, evaporator
- Type of paper
: Mentorship
Title: Three-dimensional mathematical model of the processes in
the steam generator furnace
Faculty: Fakultet strojarstva i brodogradnje Sveučilište u Zagrebu
Mentor: BOGDAN ŽELJKO
Date of defense: 07/14/93
Number of pages: 121
Author: Duić mr.sc Neven
Degree level: M.A.
Summary: Three-dimensional mathematical model of the steam generator
combustion chamber is presented. The model is mathematically represented by
the system of nonlinear elliptic partial differential equations of the
second order. It contains the flow of air, fuel and flue gas, the
combustion process, transport of oil, gas and oxygen, heat transfer inside
the gas chamber and radiative and convective heat transfer between gas and
furnace walls. The combustion process is represented by the summary
reaction modelled by the Arrhenius' reaction rate equation. Radiative heat
transfer is modelled by the zone method simplified with the assumptions of
black walls, constant absorption coefficient and one gray gas. For the
transformation of differential equations to algebraic, control volume
(SIMPLER) scheme is applied. The solving procedure is accelerated by the
multigrid method. As a global solution algorithm the iterative modification
of PISO is applied. Code ZONAL was developed in order to examine the latter
model. Comparison between the available experimental data and the
calculated results has shown good agreement.
- Type of paper
: Survey/Study
Title: Efects evaluation of sliding pressure operating regime in
the 210 MW blocks TE Sisak with the reconstructed steam generators
- Authors:
- Šerman, Nikola (46501.00000)
- Bogdan, Željko (4210.00000)
Ordering party: Hrvatska elektroprivreda HEP
Institution depot: FSB-Zagreb
Year: 1991
Number of pages: 44
- Type of paper
: Survey/Study
Title: Air flow simulation through the nuclear power plant Krško
cooling towers
- Authors:
- Bogdan, Željko (4210.00000)
Ordering party: Hrvatska elektroprivreda HEP
Institution depot: FSB-Zagreb
Year: 1991
Number of pages: 29
- Type of paper
: Survey/Study
Title: Heat flux distribution in the gas fired steam generator
furnace X-571 A/B
- Authors:
- Bogdan, Željko (4210.00000)
- Duić, Neven (179672.00000)
Ordering party: INA-Etilen
Institution depot: FSB-Zagreb
Year: 1992
Number of pages: 75
- Type of paper
: Survey/Study
Title: Design proposal of high pressure feedwater heater control
in the 320 MW plant Rijeka
- Authors:
- Šerman, Nikola (46501.00000)
- Bogdan, Željko (4210.00000)
- Lončar, Dražen (197152.00000)
Ordering party: Hrvatska elektroprivreda HEP
Institution depot: FSB-Zagreb
Year: 1993
Number of pages: 128
- Type of paper
: Survey/Study
Title: Feasibility study of the 320 MW block operating with high
pressure feedwater heater turned off
- Authors:
- Bogdan, Željko (4210.00000)
- Šerman, Nikola (46501.00000)
Ordering party: Hrvatska elektroprivreda HEP
Institution depot: FSB-Zagreb
Year: 1993
Number of pages: 37
Language: hrvatski
