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1
Content available Design and investigations of the ethanol microturbine
Kosowski K., Piwowarski M., Stępień R., Włodarski W.
Archives of Thermodynamics
|
2018
|
Vol. 39, no 2
41--54
EN
The paper presents the results of the design analysis and experimental investigations of the microturbine set consisting of the microturbine with partial admission and permanent magnet generator. The microturbine was designed for operation with the vapour of ethanol as a working fluid. Microturbine unit was tested for different parameters of the working fluid and varying the electrical load. The examples and the comparison between experiment results and numerical simulations are shown and discussed in the paper.
2
Analiza obiegów kogeneracyjnych z silnikami tłokowymi i mikroturbinami
Cieśliński A., Kosowski K., Piwowarski M., Stępień R., Włodarski W.
Rynek Energii
|
2015
|
Nr 6
41--46
PL
Przeprowadzono analizę dla układów kogeneracyjnych z mikroturbinami wykorzystującymi ciepło odpadowe z silników tłokowych. Rozważono cztery główne źródła ciepła odpadowego z silników tłokowych: spaliny wylotowe, woda chłodząca silnik, olej smarny i ciepło z systemu turbodaładowania. Obliczenia przeprowadzono dla silników General Electric Jerbacher typów: J320 GS-C25 i J416 GS-B05. Uwzględniono różne czynniki robocze siłowni (zarówno “suche”, jak i “mokre”) oraz różne cycle termodynamiczne. Nasze badanie wykazały, że wykorzystując ciepło odpadowe silników, można nie tylko podgrzewać wodę, ale także wytwarzać energię elektryczną. W ten sposób można podnieść sprawność ogólną wytwarzania energii elektrycznej nawet o 20%.
EN
The analysis was carried out for Combined Heat and Power generation systems with micro-turbines power plants working on heat rejected from the reciprocating engine. There are four main sources of heat rejected from the stroke engines: exhaust gases, engine cooling water, lubricating oil and intercooler. The calculations were performed for GE Jerbacher engines of J320 GS-C25 and J416 GS-B05 types. We considered different working media (both wet and dry fluids) and different thermodynamic cycles. Our results proved that using the heat rejected from the engines is possible not only to warm up water but also to produce some electric power and, in this way, increase the total electric output by even 20%.
3
Content available remote Experiences from operation of various expansion devices in small scale ORC
Mikielewicz D., Wajs J., Mikielewicz J., Kosowski K.
Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka
|
2014
|
nr 145
95--96
EN
The main aim of this paper was to present various expansion devices for an application in the small scale ORC system. The investigations were carried out in two parallel directions. One direction was to design and construct a device dedicated to the analyzed ORC system. The second direction was to adapt existing expansion devices for the needs of the analyzed ORC system. Four various devices were described and presented together with the experimental results. The most promising seemed to be the vapour microturbine which was built from the beginning as the device ORC system oriented.
4
Content available Remarks on aerodynamic forces in seals of turbine stages
Stępień R., Kosowski K.
Polish Maritime Research
|
2009
|
S 1
58-63
EN
This paper presents results of numerical examination of flow through over-shroud seals of turbine stages. Various labyrinth seals of different configurations and number of sealing teeth were considered. It was demonstrated that results of investigations of isolated seals cannot be directly used for analyzing turbine stage operation. Such approach may lead to relatively large errors in determining value of aerodynamic force and direction of its action.
5
Content available On the modelling of aerodynamic force coefficients for over-shroud seals of turbine stages
Włodarski W., Kosowski K.
Polish Maritime Research
|
2009
|
S 1
71-74
EN
This paper presents experimental investigations which made it possible to determine dynamic coefficients of labyrinth over-shroud seal of a model air turbine. The coefficients associate pressure forces with turbine rotor displacement, velocity and acceleration respective to turbine casing (linear model) and play important role in analyzing turbine-set dynamics. The obtained results indicated that involving serious errors can be expected in the case of application of the simplification consisting in neglecting inertia coefficients, proposed in the literature. It was simultaneously demonstrated that seals can be also met of weak damping qualities, for which to neglect damping coeffcients is allowable.
6
Content available Design analysis of turbines for co-generating micro-power plant working in accordance with organic Rankine’s cycle
Mikielewicz J., Piwowarski M., Kosowski K.
Polish Maritime Research
|
2009
|
S 1
34-38
EN
This paper presents results of a design analysis of turbines for co-generating micro-power plant working in accordance with organic Rankine’s cycle and using biofuel. The heat power range from 25 kW to 100 kW with corresponding available electric power from 2kW to 12kW, was considered. Designs of axial-flow turbines (single-stage and multi-stage ones, also those partially fed), radial-flow and axial-radial -flow ones, were analyzed. Particular variants of the solutions were compared to each other.
7
Content available Design analysis of Tesla micro-turbine operating on a low-boiling medium
Lampart P., Kosowski K., Piwowarski M., Jędrzejewski Ł.
Polish Maritime Research
|
2009
|
S 1
28-33
EN
This paper presents results of the design analysis of a Tesla bladeless turbine intended for a co-generating micro-power plant of heat capacity 20 kW, which operates in an organic Rankine cycle on a low-boiling medium. Numerical calculations of flow in several Tesla turbine models were performed for a range of design parameters. Results of investigations exhibit interesting features in the distribution of flow parameters within the turbine interdisk space. The calculated flow efficiency of the investigated Tesla turbine models show that the best obtained solutions can be competitive as compared with classical small bladed turbines.
8
Content available Intelligent microbearings project with memory of stress-strain history
Wierzcholski K., Miszczak A., Kosowski K.
Journal of KONES
|
2008
|
Vol. 15, No. 4
583-589
EN
Taking into account the increasing need of intelligent micro-bearing with memory, this paper presents the optimization, simulation and practical application of operating parameters(load carrying capacity, friction forces, friction coefficient, wear), simulation for hydrodynamic HDD micro-bearing with curvilinear nano-grooved journal profile. One of the reason of such journal profile is that this journal profile contributes to the variation (an increase or decrease) the memory capacity of HDD drive operating on hydrodynamic micro-bearings. Such properties are very important and required in HDD micro-bearings. A general theory of materials with memory is the theory developed by Noll and Koleman. The simple solid body and liquid theory presented in this paper is based on the assumption that stress is defined by a whole deformation history. The changes of micro-bearing superficial surfaces presented in this paper are described by the process of changes of mass of a body system defined by non-classical intelligent oil and bearing material properties. Scientific problems considered in the paper are focused on comparisons and practical applications of tribological processes, which occur during fluid flow around cells lubrication on the nano-surfaces in bio-bearings as well as surfaces of micro-bearings used in micro-mechanisms. Up to now, the dynamic behaviour of HDD spindle system with fluid micro-bearings was considered by Jang at al. [7]. They simulated an increase in the memory capacity by increase in the bearing width and by application herringbone or spiral grooves on the sleeve and journal surfaces of HDD micro-bearings. After proposal contained in this project it is additionally possible to make capacity memory simulations by the various shapes of micro-bearing journal application.
9
Content available Some aspects of vibration control. Part II: An optimal active controller.
Kosowski K.
Polish Maritime Research
|
2005
|
nr 1
28-31
EN
The paper presents a theoretical method for determining the optimal correction to be introduced in a mechanical system. The active control of harmonic vibrations may be achived by applying a control unit which ought to reduce the vibration amplitude of the selected elements of the system. The proposed method makes it possible to determine the controller parameters which provide an optimum value of the chosen quality index. This criterion includes the reduction of weighted amplitudes of the elements on the one hand, and minimizes energy of the control signal on the other. The described method is suitable for determination of an optimum controller of turbine rotor vibrations caused by bearing oil whip, bearing oil whirl or aerodynamic forces. For the case of rotor self-excited vibrations of aerodynamic type the linear model of excitations was compared with the neural network method.
10
Content available Some aspects of vibration control. Part I: Active and passive correction
Kosowski K.
Polish Maritime Research
|
2004
|
nr 4
22-27
EN
The paper presents a general approach to mechanical system modification aimed at controlling the steady harmonic vibrations by means of passive and active methods. The relaŹtive decrease of harmonic vibration amplitudes of selected elements of the mechanical system has been chosen as a measure of the quality of the introduced modification. The proposed theoretical method enables to determine the parameters of the system’s dynamic flexibility matrix, which show the most remarkable effect on the dynamic behaviour of the whole system. When active control is considered the method is useful in designing the structure and choosing the parameters of the control system. In certain in cases of self-excited vibration the approach helps examining the elements of the system, most responsible for this kind of excitation.
11
Steam turbine as the main ship propulsion. More than a hundred years at sea
Kosowski K.
Marine Technology Transactions. Technika Morska
|
2004
|
Vol. 15
65-80
EN
This paper is the first part of a series of articles, encompassing a short historical outline of the development of turbine ship propulsion. In this paper steam turbines are discussed, and the characteristic features of marine steam turbines are described, together with examples of marine power plants. The second part, "Gas turbine: advanced marine propulsion", concerns marine gas turbine units, and presents scientific achievements and state-of-the-art solutions in this field. Finally, the third article, "Marine turbines: cogeneration and combined propulsion systems", is devoted to gas-steam turbine combined propulsion units, the cooperation of turbines with piston engines and integrated energy and heat production in marine power plants. The discussed topic are illustrated with schemes, diagrams of specific technical solutions, and photos. The entire series of articles constitutes a collected source of information on the topic of marine steam and gas turbines.
12
Marine turbines: cogeneration and combined propulsion system
Kosowski K.
Marine Technology Transactions. Technika Morska
|
2004
|
Vol. 15
97-110
EN
This paper is the third part of a series of articles, encompassing a short historical outline of the development of turbine ship propulsion. In the first part, entitled "Steam turbine as the main ship propulsion", steam turbines are discussed, and the characteristic features of marine steam turbines are described, together with examples of marine power plants. The second part, "Gas turbine: advanced marine propulsion", concerns marine gas turbine units, and presents scientific achievements and state-of-the-art solutions in this field. Finally, the third article, "Marine turbines: cogeneration and combined propulsion systems", is devoted to gas-steam turbine combined propulsion units, the cooperation of turbines with piston engines and integrated energy and heat production in marine power plants. The discussed topic are illustrated with schemes, diagrams of specific technical solutions, and photos. The entire series of articles constitutes a collected source of information on the topic of marine steam and gas turbines.
13
Gas turbine: advanced marine propulsion
Kosowski K.
Marine Technology Transactions. Technika Morska
|
2004
|
Vol. 15
81-96
EN
This paper is the second part of a series of articles, encompassing a short historical outline of the development of turbine ship propulsion. In the first part, "Stema turbine as the main ship propulsion", steam turbines are discussed, and the characteristic features of marine steam turbines are described, together with examples of marine power plants. This part concerns marine gas turbine units, and presents scientific achievements and state-of-the-art solutions in this field. Finally, the third article, "Marine turbines: cogeneration and combined propulsion systems", is devoted to gas-steam turbine combined propulsion units, the cooperation of turbines with piston engines and inegrated energy and heat production in marine power plants. The discussed topics are illustrated with schemes, diagrams of specific technical solutions, and photos. The entire series of articles constitutes a collected source of information on the topic of marine steam and gas turbines.
14
Content available remote Theoretical investigations into flows in rotor blade shroud clearance
Kosowski K., Stępień R.
Transactions of the Institute of Fluid-Flow Machinery
|
2003
|
nr 113
249-262
EN
Asymmetrical shroud clearance, resulting from rotor-stator eccentricity, causes so called aerodynamic forces, which in turn lead to self-excited vibrations of rotor systems. Numerical investigations were carried out to show how CFD code can cope with determination of the pressure field in a rotor blade tip gap. Calculations of flows on the whole turbine stage circumference were performed in order to investigate the aerodynamic forces generated above the shroud due to asymmetrical pressure field caused by rotor-stator eccentricity. The 3D calculations of axial turbine of impulse type performed using CFD code Fluent. Different types of shroud geometry were considered. The Multiple Reference Frame method and the Sliding Mesh method were applied and some of the results were compared with the experimental data. Both the techniques appeared to give results similar to those obtained in the experiments. The experimental investigations into the pressure field in the shroud clearance were performed on a one-stage air model turbine. The calculations and measurements of pressure distribution were carried out for different rotor speeds and different turbine load.
15
Content available remote Research into flows in turbine blade seals. Part III: Numerical calculations versus experiment
Kosowski K., Stępień R., Piwowarski M., Badur J.
TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
|
2003
|
Vol. 7, No 3
329-336
EN
Experimental and theoretical investigations of the pressure field in the shroud clearance were performed on a one-stage air model turbine of the impulse type. Measurements of pressure distribution were carried out for various rotor speeds and turbine loads. 3D calculations of flows in this turbine were performed using the FLUENT CFD code. The calculations were carried out for variants which had been measured experimentally. The experimental data have been compared to theoretical results obtained with 3D codes for turbomachinery calculations. The Sliding Mesh and Multiple Reference methods have given very similar results of average values of pressure distribution and the velocity field in the shroud clearance. These results correspond to the experimental data. The pressure pulsations were determined only by the Sliding Mesh method, and these results have also been compared with the experiment. Stage flow calculations carried by the Sliding Mesh method with a structural shroud mesh and with a minimum number of 2-2.5 million cells have given a range of non-stationary pressure pulsations corresponding to the experimental data.
16
Content available remote Research into flows in turbine blade seals. Part II: Numerical analysis
Stępień R., Kosowski K., Badur J.
TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
|
2003
|
Vol. 7, No 3
319-327
EN
3D calculations of an axial model turbine of the impulse type were performed using the FLUENT CFD code. The calculations were carried out for variants which had been measured experimentally. Special attention was paid to the pressure field in the rotor blade shroud clearance. The Multiple Reference Frame method, the Mixing Plane method and the Sliding Mesh method were applied, and meshes of different types and configurations were used for calculations. Only the Sliding Mesh technique appeared to describe non-stationary effects and pressure pulsations in the turbine flow channels and clearances. In this part of the paper, numerical analysis is described, while the comparison between the experimental and the calculated results is presented in part III.
17
Content available remote Research into flows in turbine blade seals. Part I: research methods
Badur J., Kosowski K., Stępień R., Piwowarski M.
TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
|
2003
|
Vol. 7, No 3
309-317
EN
Flows in the shroud clearance affect leakage losses and, thus, the turbine stage efficiency. However, at the same time, the distribution of pressure in the seal gaps plays an important role in the generation of the so-called "pressure forces", which may cause self-excited rotor vibrations of the aerodynamic type. Our investigations were carried out in order to show how a CFD code can cope with determining the pressure field in a rotor-blade shroud clearance. Experimental investigations of the pressure field in the shroud clearance were performed on a one-stage air model turbine of the impulse type. Measurements of pressure distribution were carried out for various rotor speeds and turbine loads. 3D calculations of flows in the model turbine were performed using the FLUENT CFD code. The calculations were carried out for the same variants which had been measured experimentally. In this part of the paper, the experimental stand and the numerical methods are described, while a detailed numerical analysis and a comparison between the experimental and the calculated results are presented in parts II and III, respectively.
18
Wykorzystanie odpadów i oczyszczanie spalin z zanieczyszczeń
Sokołowski J., Kosowski K., Kwiatkowski Jarosław
Energetyka
|
2003
|
nr 1
33-41
19
Content available remote Application of 3D flow solver in education of students
Kosowski K.
TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk
|
2002
|
Vol. 6, No 4
621-629
EN
The development of 3D numerical methods enables the estimation of flow parameters in any section of the channels and in this way the complex phenomenon of generation of losses can be investigated. Application of 3D solver helps in better understanding of flow behaviour in turbine stages, while basing on the results of calculations of stages of different geometries, it is possible to show the effect of different design parameters on the turbine stage output and its efficiency. The paper presents the examples of application of modern computer programs for teaching turbomachinery problems, for research flows in turbine stages and for solving design tasks. Some examples of students' projects are also included.
20
Wytwarzanie energii elektrycznej i ciepła z wykorzystaniem odpadów komunalnych i przemysłowych. Analiza techniczna dla warunków polskich
Sokołowski J., Kwiatkowski J., Kosowski K.
Energetyka
|
2002
|
nr 9
678-681
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