Paweł Niegodajew - Academia.edu (original) (raw)
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Papers by Paweł Niegodajew
Applied Mathematical Modelling, 2016
The paper is devoted to CFD modelling of the CO 2 capture from flue gases with the use of chemica... more The paper is devoted to CFD modelling of the CO 2 capture from flue gases with the use of chemical absorption. The model incorporates various physico-chemical submodels, in particular Eulerian countercurrent 2-phase gas-liquid flow in porous media, chemical reaction of CO 2 absorption/desorption combined with heat release/consumption, inter-phase heat transfer and the water evaporation/condensation phenomena. The special attention has been put on flow hydrodynamics in porous region, where a flow resistance and a liquid holdup have to be modelled with special care. Moreover, a flow redistribution model has been adopted in a porous region in order to adequately reconstruct liquid behaviour due to the geometry constraints of packed bed filling elements. Due to high complexity of the model, its development and testing has been performed with the use of a number of simplified models. Test simulations have shown a good agreement with experimental data acquired at the reference pilot CCS installation proving the model relevance and its usefulness to industrial applications.
Journal of Power Technologies, Dec 3, 2013
The paper concerns research aimed at developing a computational fluid dynamics (CFD) model of an ... more The paper concerns research aimed at developing a computational fluid dynamics (CFD) model of an aminebased carbon dioxide capture process in post-combustion capture (PCC) technology. A numerical model of the absorber column (the first stage of PCC cycle) including complex hydrodynamics, heat transfer and absorption reaction involving monoethanolamine (MEA) was developed and described in detail in . This paper focuses on the second stage of the PCC cycle: the desorber (stripper) column. An Eulerian multiphase model was adopted to resolve two-phase counter-current gas-liquid flow in a porous region with desorption reaction, multiphase heat transfer and evaporation/condensation phenomena. The preliminary calculations were performed on simplified geometry of the stripper column in order to reduce the computational time required. The results showed physically correct behavior, proving its relevance and utility for practical applications.
Applied Thermal Engineering, 2016
The study presented in this paper deals with the analysis of operating conditions of a modern sup... more The study presented in this paper deals with the analysis of operating conditions of a modern supercritical power plant. The 460 MW reference thermal cycle, which is based on the Lagisza supercritical, coal fired power plant was selected for this study. The thermodynamic analysis was performed with the use of the industrial software package IPSEpro, designed for power plant engineering. The main objective was to demonstrate the role of supercritical parameters in enhancing the efficiency of the thermodynamic process. It was done among the others by the comparative analysis of two thermal cycles, one working with standard and the other with supercritical parameters. Apart from nominal operating conditions part load operation was analyzed.
Nowadays, there are many commercial software allowing to perform 0-dimennsional (0D) analysis of ... more Nowadays, there are many commercial software allowing to perform 0-dimennsional (0D) analysis of power plant. Some of these programs, are equipped with their own optimization tools, however, as is so often the case, most of them are not able to carry out a multi-variable optimisation concerning greater number of decision parameters. This paper presents application of the integrated package containing the IPSEpro and MATLAB software for numerical optimisation of ultra-supercritical thermal cycle. For that purpose a new concept of 900 MW ultra-supercritical power unit was examined. To increase the efficiency and flexibility of calculations three different non-gradient methods were introduced into the code, i.e.: Nelder-Mead, Hook-Jeeves and Rosenbrock. It was shown that all of three considered methods can find their usefulness in optimization process of power plant thermal cycle giving the rise in the efficiency by about 0.3%. The significant advantage of the Rosenbrock one is the lower cost of computation and the low sensitivity of the cost to the number of independent variable.
A new optimization technique was developed at Institute of Thermal Machinery allowing to improve ... more A new optimization technique was developed at Institute of Thermal Machinery allowing to improve power plant efficiency. This approach was integrated with one of the most advanced procedures used in the economic analysis of power systems i.e. Revenue Requirement Method (RRM). RRM allows for a detailed estimation of the investment cost, thereby provides the value of the minimum acceptable cost recovery to the investor. A new concept of 900 MW power unit for ultra-supercritical parameters was chosen as an object of the study. Thermo-economic analysis using the efficiency of the installation as an objective function was performed. Bleed and outlet pressures of high pressure turbine were selected as decision variables. The calculations of the power plant thermal cycle were conducted with the use of IPSEpro software. The RRM method was implemented in MOExcel software while power plant optimization was performed in MATLAB environment. Rosenbrock algorithm was used to find optimal values of bleed and outlet pressures of high pressure turbine. 0.15 percentage point rise in efficiency was achieved. However, analysis of total investment cost indicated that such increase in efficiency gained by change high pressure turbine operating pressures is economically unjustified.
The paper is devoted to CFD modelling of the CO2 capture from flue gases with the use of chemical... more The paper is devoted to CFD modelling of the CO2 capture from flue gases with the use of chemical absorption. The model incorporates various physico-chemical submodels, in particular Eulerian countercurrent 2-phase gas-liquid flow in porous media, chemical reaction of CO2 absorption/desorption combined with heat release/consumption, inter-phase heat transfer and the water evaporation/condensation phenomena. The special attention has been put on flow hydrodynamics in porous region, where a flow resistance and a liquid holdup have to be modelled with special care. Moreover, a flow redistribution model has been adopted in a porous region in order to adequately reconstruct liquid be haviour due to the geometry constraints of packed bed filling elements. Due to high complexity of the model, its development and testing has been performed with the use of a number of simplified models. Test simulations have shown a good agreement with experimental data acquired at the reference pilot CCS in...
Journal of Physics: Conference Series, 2014
The paper is devoted to the computational fluid dynamics (CFD) simulation of liquid spreading pro... more The paper is devoted to the computational fluid dynamics (CFD) simulation of liquid spreading process in a packed bed. The volume of fluid (VOF) approach was applied to simulate the flow in a realistic porous region composed of 6mm Raschig rings. Modelling results were used to determine the probability density function (PDF) distribution of liquid velocity vector orientation angle which was then implemented into 2-fluid Euler-Euler multiphase model of packing column. The simulation showed that the model is capable to simulate adequately the liquid redistribution in a porous region being, however, much more efficient computationally than the VOF method.
Chemical and Process Engineering, 2000
The paper deals with numerical modelling of carbon dioxide capture by amine solvent from flue gas... more The paper deals with numerical modelling of carbon dioxide capture by amine solvent from flue gases in post-combustion technology. A complex flow system including a countercurrent two-phase flow in a porous region, chemical reaction and heat transfer is considered to resolve CO 2 absorption. In order to approach the hydrodynamics of the process a two-fluid Eulerian model was applied. At the present stage of model development only the first part of the cycle, i.e. CO 2 absorption was included. A series of parametric simulations has shown that carbon dioxide capture efficiency is mostly influenced by the ratio of liquid (aqueous amine solution) to gas (flue gases) mass fluxes. Good consistency of numerical results with experimental data acquired at a small-scale laboratory CO 2 capture installation (at the Institute for Chemical Processing of Coal, Zabrze, Poland) has proved the reliability of the model.
Archives of Thermodynamics, 2000
The paper deals with the computational fluid dynamics modelling of carbon dioxide capture from fl... more The paper deals with the computational fluid dynamics modelling of carbon dioxide capture from flue gases in the post combustioncapture method, one of the available carbon capture and storage technologies. 30% aqueous monoethanolamine solution was used as a solvent in absorption process. The complex flow system including multiphase countercurrent streams with chemical reaction and heat transfer was considered to resolve the CO2 absorption. The simulation results have shown the realistic behaviour and good consistency with experimental data. The model was employed to analyse the influence of liquid to gas ratio on CO2 capture efficiency.
The paper deals with the numerical modelling of carbon dioxide capture from flue gases in the pos... more The paper deals with the numerical modelling of carbon dioxide capture from flue gases in the post combustion method, the most preferred option among the carbon capture and storage (CCS) technologies. The process is performed by means of a chemical absorption of CO2 by aqueous solution of monoethanolamine (MEA) in the absorber column filled in with the porous material ensuring the enlarged contact area between fluids. The complex flow system including multiphase countercurrent streams with chemical reaction and heat transfer is considered to resolve the CO2 capture. The Euler-Euler model was applied to treat the gas-liquid system and the simplified chemistry has been adopted to describe the CO2 absorption. The absorber model follows the small-scale pilot CO2 capture installation being ready for tests at the Institute for Chemical Processing of Coal, Zabrze. The model developed has been used to conduct a series of test simulations both for nonreacting and reacting conditions. The res...
Applied Mathematical Modelling, 2016
The paper is devoted to CFD modelling of the CO 2 capture from flue gases with the use of chemica... more The paper is devoted to CFD modelling of the CO 2 capture from flue gases with the use of chemical absorption. The model incorporates various physico-chemical submodels, in particular Eulerian countercurrent 2-phase gas-liquid flow in porous media, chemical reaction of CO 2 absorption/desorption combined with heat release/consumption, inter-phase heat transfer and the water evaporation/condensation phenomena. The special attention has been put on flow hydrodynamics in porous region, where a flow resistance and a liquid holdup have to be modelled with special care. Moreover, a flow redistribution model has been adopted in a porous region in order to adequately reconstruct liquid behaviour due to the geometry constraints of packed bed filling elements. Due to high complexity of the model, its development and testing has been performed with the use of a number of simplified models. Test simulations have shown a good agreement with experimental data acquired at the reference pilot CCS installation proving the model relevance and its usefulness to industrial applications.
Journal of Power Technologies, Dec 3, 2013
The paper concerns research aimed at developing a computational fluid dynamics (CFD) model of an ... more The paper concerns research aimed at developing a computational fluid dynamics (CFD) model of an aminebased carbon dioxide capture process in post-combustion capture (PCC) technology. A numerical model of the absorber column (the first stage of PCC cycle) including complex hydrodynamics, heat transfer and absorption reaction involving monoethanolamine (MEA) was developed and described in detail in . This paper focuses on the second stage of the PCC cycle: the desorber (stripper) column. An Eulerian multiphase model was adopted to resolve two-phase counter-current gas-liquid flow in a porous region with desorption reaction, multiphase heat transfer and evaporation/condensation phenomena. The preliminary calculations were performed on simplified geometry of the stripper column in order to reduce the computational time required. The results showed physically correct behavior, proving its relevance and utility for practical applications.
Applied Thermal Engineering, 2016
The study presented in this paper deals with the analysis of operating conditions of a modern sup... more The study presented in this paper deals with the analysis of operating conditions of a modern supercritical power plant. The 460 MW reference thermal cycle, which is based on the Lagisza supercritical, coal fired power plant was selected for this study. The thermodynamic analysis was performed with the use of the industrial software package IPSEpro, designed for power plant engineering. The main objective was to demonstrate the role of supercritical parameters in enhancing the efficiency of the thermodynamic process. It was done among the others by the comparative analysis of two thermal cycles, one working with standard and the other with supercritical parameters. Apart from nominal operating conditions part load operation was analyzed.
Nowadays, there are many commercial software allowing to perform 0-dimennsional (0D) analysis of ... more Nowadays, there are many commercial software allowing to perform 0-dimennsional (0D) analysis of power plant. Some of these programs, are equipped with their own optimization tools, however, as is so often the case, most of them are not able to carry out a multi-variable optimisation concerning greater number of decision parameters. This paper presents application of the integrated package containing the IPSEpro and MATLAB software for numerical optimisation of ultra-supercritical thermal cycle. For that purpose a new concept of 900 MW ultra-supercritical power unit was examined. To increase the efficiency and flexibility of calculations three different non-gradient methods were introduced into the code, i.e.: Nelder-Mead, Hook-Jeeves and Rosenbrock. It was shown that all of three considered methods can find their usefulness in optimization process of power plant thermal cycle giving the rise in the efficiency by about 0.3%. The significant advantage of the Rosenbrock one is the lower cost of computation and the low sensitivity of the cost to the number of independent variable.
A new optimization technique was developed at Institute of Thermal Machinery allowing to improve ... more A new optimization technique was developed at Institute of Thermal Machinery allowing to improve power plant efficiency. This approach was integrated with one of the most advanced procedures used in the economic analysis of power systems i.e. Revenue Requirement Method (RRM). RRM allows for a detailed estimation of the investment cost, thereby provides the value of the minimum acceptable cost recovery to the investor. A new concept of 900 MW power unit for ultra-supercritical parameters was chosen as an object of the study. Thermo-economic analysis using the efficiency of the installation as an objective function was performed. Bleed and outlet pressures of high pressure turbine were selected as decision variables. The calculations of the power plant thermal cycle were conducted with the use of IPSEpro software. The RRM method was implemented in MOExcel software while power plant optimization was performed in MATLAB environment. Rosenbrock algorithm was used to find optimal values of bleed and outlet pressures of high pressure turbine. 0.15 percentage point rise in efficiency was achieved. However, analysis of total investment cost indicated that such increase in efficiency gained by change high pressure turbine operating pressures is economically unjustified.
The paper is devoted to CFD modelling of the CO2 capture from flue gases with the use of chemical... more The paper is devoted to CFD modelling of the CO2 capture from flue gases with the use of chemical absorption. The model incorporates various physico-chemical submodels, in particular Eulerian countercurrent 2-phase gas-liquid flow in porous media, chemical reaction of CO2 absorption/desorption combined with heat release/consumption, inter-phase heat transfer and the water evaporation/condensation phenomena. The special attention has been put on flow hydrodynamics in porous region, where a flow resistance and a liquid holdup have to be modelled with special care. Moreover, a flow redistribution model has been adopted in a porous region in order to adequately reconstruct liquid be haviour due to the geometry constraints of packed bed filling elements. Due to high complexity of the model, its development and testing has been performed with the use of a number of simplified models. Test simulations have shown a good agreement with experimental data acquired at the reference pilot CCS in...
Journal of Physics: Conference Series, 2014
The paper is devoted to the computational fluid dynamics (CFD) simulation of liquid spreading pro... more The paper is devoted to the computational fluid dynamics (CFD) simulation of liquid spreading process in a packed bed. The volume of fluid (VOF) approach was applied to simulate the flow in a realistic porous region composed of 6mm Raschig rings. Modelling results were used to determine the probability density function (PDF) distribution of liquid velocity vector orientation angle which was then implemented into 2-fluid Euler-Euler multiphase model of packing column. The simulation showed that the model is capable to simulate adequately the liquid redistribution in a porous region being, however, much more efficient computationally than the VOF method.
Chemical and Process Engineering, 2000
The paper deals with numerical modelling of carbon dioxide capture by amine solvent from flue gas... more The paper deals with numerical modelling of carbon dioxide capture by amine solvent from flue gases in post-combustion technology. A complex flow system including a countercurrent two-phase flow in a porous region, chemical reaction and heat transfer is considered to resolve CO 2 absorption. In order to approach the hydrodynamics of the process a two-fluid Eulerian model was applied. At the present stage of model development only the first part of the cycle, i.e. CO 2 absorption was included. A series of parametric simulations has shown that carbon dioxide capture efficiency is mostly influenced by the ratio of liquid (aqueous amine solution) to gas (flue gases) mass fluxes. Good consistency of numerical results with experimental data acquired at a small-scale laboratory CO 2 capture installation (at the Institute for Chemical Processing of Coal, Zabrze, Poland) has proved the reliability of the model.
Archives of Thermodynamics, 2000
The paper deals with the computational fluid dynamics modelling of carbon dioxide capture from fl... more The paper deals with the computational fluid dynamics modelling of carbon dioxide capture from flue gases in the post combustioncapture method, one of the available carbon capture and storage technologies. 30% aqueous monoethanolamine solution was used as a solvent in absorption process. The complex flow system including multiphase countercurrent streams with chemical reaction and heat transfer was considered to resolve the CO2 absorption. The simulation results have shown the realistic behaviour and good consistency with experimental data. The model was employed to analyse the influence of liquid to gas ratio on CO2 capture efficiency.
The paper deals with the numerical modelling of carbon dioxide capture from flue gases in the pos... more The paper deals with the numerical modelling of carbon dioxide capture from flue gases in the post combustion method, the most preferred option among the carbon capture and storage (CCS) technologies. The process is performed by means of a chemical absorption of CO2 by aqueous solution of monoethanolamine (MEA) in the absorber column filled in with the porous material ensuring the enlarged contact area between fluids. The complex flow system including multiphase countercurrent streams with chemical reaction and heat transfer is considered to resolve the CO2 capture. The Euler-Euler model was applied to treat the gas-liquid system and the simplified chemistry has been adopted to describe the CO2 absorption. The absorber model follows the small-scale pilot CO2 capture installation being ready for tests at the Institute for Chemical Processing of Coal, Zabrze. The model developed has been used to conduct a series of test simulations both for nonreacting and reacting conditions. The res...