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1

Thermodynamic analysis and profitability study of a power unit with an added CO2 capture plant

Kowalczyk Ł., Niegodajew P., Drobniak S., Elsner W.

Journal of Power Technologies

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2016

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Vol. 96, nr 4

276--284

EN

Concerns over greenhouse gas emissions are driving a requirement for newly built coal power units to satisfy the so-called “capture ready” conditions. This paper presents the a thermo-economic analysis supplemented by a cost evaluation of a power unit for ultra-supercritical parameters expanded by an amine-based CO2 capture plant. The analysis was performed with the use of an integrated package containing the IPSEpro, MATLAB and Revenue Requirement Method implemented in MOExcel. The 0D model of a post combustion capture installation was developed based on complex CFD calculations of the absorber and stripper. A number of CFD simulations were conducted to create a large database, which was then utilized to develop suitable correlations describing the process Thermodynamic and economic calculations were performed in respect of a power plant coupled with a CO2 separation unit for a varying ratio of amine solvent to the exhaust gas stream (L/G). A local minimum for reboiler heat duty was found for L/G≈3.5 revealing the optimal post combustion capture configuration. It was observed that complementing the power unit with a post-combustion capture (PCC) installation causes a slight increase in the investment costs due to the drop in efficiency, but more important is the rise in total cost due to the investment associated with the CO2 capture plant. It was found that about 14 years is required to compensate the investment cost of the PCC installation.

2

Two–Phase Flow in Porous Bed with Chemical Reaction

Niegodajew P, Asendrych D., Drobniak S., Elsner W.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2013

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z. 101

75--76

EN

Continuous growth of CO2 emission is one of the most important threats of today’s power industry. Among the alternatives allowing to solve that problem, carbon capture and storage (CCS) technology seems to be a very promising option. With this method the flue gases are being sent through the absorber where CO2 is captured by aqueous amine solution flowing countercurrently. Both phases pass through the packed bed where most of the chemical reaction occurs due to the enlarged contact area between phases. The research performed so-far included investigations with the use of laboratory or pilot installations as well as numerical modelling by means of simplified 0D or 1D models. These methods have, however, limited capabilities as they do not allow to have an insight into the details of the process.

3

Numerical modelling of CO2 desorption process coupled with phase transformation and heat transfer in CCS installation

Niegodajew P., Asendrych D., Drobniak S.

Journal of Power Technologies

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2013

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Vol. 93, nr 5

354--361

EN

The paper concerns the research aimed at developing the computational fluid dynamics (CFD) model of amine based carbon dioxide capture process in post combustion capture (PCC) technology. Numerical model of absorber column (being the first stage of PCC cycle) including complex hydrodynamics, heat transfer and absorption reaction with the use of monoethanolamine (MEA) has already been developed and described in detail in [1, 2]. This paper focuses on the second stage of PCC cycle i.e. desorber (stripper) column. Eulerian multiphase model was adopted to resolve two-phase countercurrent gas-liquid flow in porous region with desorption reaction, multiphase heat transfer and evaporation/condensation phenomena. The preliminary calculations were performed on simplified geometry of stripper column in order to reduce the computational time required. Results have shown a physically correct behaviour, proving its relevance and its usefulness to practical applications.

4

Thermoeconomic analysis of supercritical coal fired power plant using RRM method

Kowalczyk Ł., Elsner W., Drobniak S.

Energetyka

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2013

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nr 11

803--807

EN

The paper presents the thermoeconomic analysis for a novel concept of an ultra-supercritical coal-fired steam cycle. The main purpose of this paper was to show basic assumption of RRM method which was used for three different structural configurations of a power unit. The calculations were performed with IPSEpro and RRM methods. Our results confirm the literature data that RRM method is the most suitable one for the energy sector. Additionally this method is one of the most advanced procedures used in the financial analysis. It allows to estimate investment costs for which the revenues provide minimum acceptable cost return for investors. This method was implemented for IPSEpro and MO Excel software. For PEC calculation a new library, called APP_ECO_Lib, was created. Three cases with different structure configurations were analysed. From the viewpoint of thermodynamic the case nr 3 is the most effective system, as the increase of efficiency seems to be sufficient to compensate investment cost associated with structural change. It should be mentioned that some of calculation uncertainty is related with material factors. The analyses have shown that calculations for critical and under-critical steam cycles are sufficiently reliable. However, there is a lack of data for new materials which will be used for design of for ultra-supercritical steam cycle components, that is why calculations for these cases may be biased with some error which is difficult to estimate.

PL

Artykuł przedstawia analizę termoekonomiczną nowatorskiej koncepcji dla bloków realizujących cykl parowy o parametrach supernadkrytycznych i opalanych węglem kamiennym. Głównym celem tego artykułu jest pokazanie podstawowych założeń metody RRM, która została wykorzystana dla trzech różnych konfiguracji struktury bloku energetycznego. Obliczenia zostały wykonane przy pomocy metod IPSEpro i RRM. Osiągnięte przez nas wyniki potwierdzają publikowane dane, że metoda RRM jest najbardziej przydatną metodą dla sektora energetycznego. Metoda ta została zaimplementowana dla oprogramowania IPSEpro i MO Excel. Na użytek obliczeń PEC została opracowana nowa biblioteka o nazwie APP_ECO_Lib. Przeanalizowano trzy przypadki różnych konfiguracji strukturalnych. Z punktu widzenia termodynamiki, przypadek nr 3 jest systemem najbardziej efektywnym, jako że wzrost wydajności wydaje się być wystarczający dla kompensacji kosztów poniesionych w związku ze zmianą strukturalną. Analizy wykazują, że obliczenia przeprowadzane dla krytycznego i podkrytycznego cyklu parowego są wystarczająco wiarygodne. Brakuje jednakże danych dotyczących nowych materiałów, które będą wkrótce wykorzystywane przy projektowaniu elementów instalacji na potrzeby supernadkrytycznych cykli parowych. Dlatego też obliczenia dla takich przypadków mogą być obciążone pewnymi błędami, których wartości są trudne do oszacowania.

5

CFD modelling of CO2 capture in a packed bed by chemical absorption

Asendrych D., Niegodajew P., Drobniak S.

Chemical and Process Engineering

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2013

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Vol. 34, nr 2

269--282

EN

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 CO2 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. CO2 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 CO2 capture installation (at the Institute for Chemical Processing of Coal, Zabrze, Poland) has proved the reliability of the model.

6

Numerical analysis of CO2 capture efficiency in post combustion CCS technology in terms of varying flow conditions

Niegodajew P., Asendrych D., Drobniak S.

Archives of Thermodynamics

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2013

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Vol. 34, no. 4

123--136

EN

The paper deals with the computational fluid dynamics modelling of carbon dioxide capture from flue gases in the post combustion-capture 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.

7

Thermodynamic analysis of a thermal cycle of supercritical power plant

Elsner W., Kowalczyk Ł., Niegodajew P., Drobniak S.

Mechanics and Mechanical Engineering

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2011

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Vol. 15, nr 3

217-225

EN

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 Łagisza 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.

8

Application of VITA technique for detection of the organized structures present in a turbulent boundary layer under an adverse pressure gradient

Dróżdż A., Elsner W., Drobniak S.

Archives of Mechanics

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2011

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Vol. 63, nr 2

183-199

EN

The paper concerns experimental investigations of turbulent boundary layer (TBL), developing on a flat plate at Reynolds number based on momentum thickness= 3000 under an adverse pressure gradient (APG) corresponding to the case of pressure variation at axial compressor blading. In particular, the paper deals with the analysis of bursting phenomena and coherent structures activity in TBL with the use of VITA technique. The interpretation of coherent structures was based on the analysis of conditionally averaged traces of u and v velocity components recorded by X-wire probe in several boundary layer regions. The paper describes the modification introduced into the VITA method, which enables to distinguish four types of coherent structures. This modification relies on the detection of instantaneous positive or negative gradients of u and v velocity traces. It was found that bursting process under the influence of adverse pressure gradient is damped near the wall and this phenomenon is even more pronounced in the outer region of turbulent boundary layer. Furthermore, the paper gives the consistent proof, that vortices developing in TBL create the effect of bursting present in velocity signal.

9

Experimental analysis of velocity field structure in isothermal countercurrent jets

Wojciechowska B., Domagała P., Drobniak S.

Journal of Theoretical and Applied Mechanics

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2009

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Vol. 47 nr 1

3-16

EN

The paper presents results of experimental analysis of the flowfield in isothermal countercurrent round jets. The velocity measurements were carried out by means of a hot-wire anemometry. The instantaneous signals collected during the experiment were digitally processed and used to determine the statistics of velocity fields and distributions of turbulence scales. The results revealed that the fluid aspiration at the jet periphery significantly influences the mixing and entrainment in the free flow.

PL

Artykuł przedstawia wyniki eksperymentalnej analizy pola prędkości izotermicznych strug przeciwbieżnych. Eksperyment przeprowadzony został z wykorzystaniem pionowego tunelu aerodynamicznego wyposażonego w układ dwóch dysz do generacji osiowosymetrycznych, koncentrycznych strug przeciwbieżnych. Pomiar prędkości został wykonany przy użyciu termoanemometrii. Uzyskane w trakcie badań wyniki pokazują, że zewnętrzna struga zwrotna ma istotny wpływ na rozwój wewnątrz strugi osiowosymetrycznej. Najistotniejszy parametr niniejszych badań, tzn. stosunek prędkości wewnętrznej i zewnętrznej strugi, wykazał wartość krytyczną I = 0.2. Prawidłowość tę zaobserwowano dla obydwu badanych liczb Reynoldsa, chociaż dla niższych liczb Reynoldsa tendencja ta była bardziej widoczna. Nowym elementem poznawczym było określenie rozkładu charakterystycznych skal turbulencji, które według wiedzy autorów nie były prezentowane w literaturze dla badanego przepływu.

10

The structure of turbulent boundary layer with adverse pressure gradient corresponding to turbomachinery condition

Materny M, Dróżdż A, Drobniak S, Elsner W

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2008

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nr 133

221--228

EN

The paper deals with the experimental analysis of turbulent boundary layer at the flat plate for large value of Reynolds number equal Reθ ≈ 3000. The adverse pressure gradient generated by curvature of the upper wall corresponded to the case of pressure variation in axial compressor. The fully developed turbulence structure was achieved by proper triggering of the boundary layer. The mean and turbulent flow – fields were investigated with the use of hot–wire technique.

11

Prediction of laminar – turbulent transition on highly-loaded turbomachinery profiles

Drobniak S, Elsner W

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2008

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nr 133

95--102

EN

The paper presents a review of the current knowledge concerning the modelling of laminar – turbulent transition on turbomachinery blading. The most important physical features of laminar – turbulent transition are reviewed and their consequences for CFD modelling are discussed. The main features and assumptions of existing models are discussed with special reference to intemittency based models. The limitations of existing models are discussed and the reasons why intermittency – based models seem to be a promising perspective are outlined. The main features of intermittency – based model developed at the Institute of Thermal Machinery and extended by in-house correlations on onset location and transition length are also presented and discussed.

12

Application of oil – fringe interferometry for measurements of wall shear stress in turbulent boundary layer

Dróżdż A, Elsner W, Drobniak S

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2008

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nr 133

103--110

EN

The measurement of skin friction is presently recognized as a critical element of aerodynamic testing. Skin friction is necessary to characterize wall-bounded flows, to provide critical information necessary for computational simulations and to serve as a sensitive quantity for use in flow-control applications. The paper is aimed at presenting a new technique of precise skin friction measurement applied for a flat plate at the adverse pressure gradient corresponding to pressure distribution in the axial compressor.

13

Turbulencja - od losowości do determinizmu

Boguslawski A., Drobniak S., Tyliszczak A.

Modelowanie Inżynierskie

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2008

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T. 5, nr 36

41-48

PL

Praca poświęcona jest omówieniu aktualnych tendencji w matematycznym modelowaniu przepływów turbulentnych. Przedstawiono obecny stan wiedzy w dziedzinie modelowania turbulencji, który stanowi podstawę wykorzystywanych obecnie kodów CFD, należących do klasy RANS. Scharakteryzowano ograniczenia modeli RANS i omówiono założenia metod DNS stanowiących wzorzec rozwiązań dla problematyki turbulencji. Szczególną uwagę poświęcono omówieniu metod LES, które stanowi przyszłościowe rozwiązanie problemu modelowania przepływów turbulentnych.

EN

The paper presents contemporary developments in numerical modelling of turbulence with special reference to Large Eddy Simulation (LES) methods. The limitations of conventional turbulence models based on stochastic methodology have been discussed and reasons for development of deterministic approach were outlined. It was shown that even the fastest available computers restrict the possible DNS (Direct Numerical Simulation) solutions to small Reynolds numbers. Finally the basic assumptions have been formulated for the LES formalism, that seems to offer the possibility for industrial flow modelling

14

Some remarks on modelling and simulation of turbulence

Drobniak S., Bogusławski A., Tyliszczak A.

Journal of Theoretical and Applied Mechanics

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2008

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Vol. 46 nr 2

243-256

EN

The paper presents contemporary developments in the field of deterministic description of turbulence with special reference to Large Eddy Simulation (LES) methods. The limitations of conventional turbulence modelling based on stochastic methodology have been discussed, and reasons for development of deterministic approach outlined. It has been shown that the computational power of the fastest available computers restrict possible DNS (Direct Numerical Simulation) solutions to the range of small Reynolds numbers. Finally, basic assumptions have been formulated for the LES formalism that seem to offer a reasonable compromise between the tendency towards the deterministic solution to Navier-Stokes equations and the existing computational resources.

PL

Praca przedstawia współczesny stan wiedzy w dziedzinie numerycznego modelowania turbulencji ze szczególnym uwzględnieniem metody LES (ang. Large Eddy Simulation). Przedstawiono ograniczenia modeli turbulencji typu RANS, opartych o uśrednione w czasie równania Reynoldsa oraz wskazano perspektywy deterministycznego ujęcia turbulencji z użyciem metod DNS (ang. Direct Numerical Simulation). Wykazano również, że możliwości najszybszych dostępnych obecnie komputerów ograniczają możliwe obszary aplikacji DNS do przepływów o stosunkowo niskich liczbach Reynoldsa. Następnie sformułowano podstawowe zależności dla metod LES i wskazano ich perspektywiczne znaczenie dla inżynierskiego modelowania przepływów turbulentnych.

15

Experimental analysis of droplet generation

Wojciechowski G., Domagała P., Drobniak S.

Archives of Thermodynamics

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2008

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Vol. 29, no. 3

45-58

EN

The paper presents results of experimental analysis concerning the primary breakup of liquid jet. The experimental was carried out with two types of injectors based on Rayleigh phenomenon. The breakup process was investigated by optical methods based on fast micro photography. The results obtained constitute the data base for verification of numerical modelling of liquid jet breakup.

16

Experimental analysis of turbulent boundary layer under the influence of adverse pressure gradient

Materny M., Dróżdż A., Drobniak S., Elsner W.

Archives of Mechanics

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2008

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Vol. 60, nr 6

449-466

EN

The paper deals with the experimental analysis of turbulent boundary layer at the flat plate for large value of Reynolds number equal Re??3000. The adverse pressure gradient is generated by curvature of the upper wall and corresponds to the case of pressure variation in axial compressor. The analysis is concentrated on the problem of scaling of turbulent boundary layer and on the physical background behind scaling laws being compared. The results obtained suggest, that boundary layer at APG conditions requires two velocity scales, i.e. inner (imposed by inner boundary condition) and outer (imposed by outer layer) velocity scales.

17

Determination of production rate of turbulent spots using wavelet analysis

Elsner W., Wysocki M., Drobniak S.

Inżynieria Chemiczna i Procesowa

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2006

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T. 27, z. 3/1

935-950

EN

The paper deals with the analysis of laminar-turbulent transition process in the flow around the turbomachinery blading. The characteristic feature of laminar-turbulent transition process is the appearance of well-defined structures. commonly known as turbulent spots. The basic difficulty in analysis of turbulent spots, which occurs randomly in time, is their discrimination from the highly unsteady background of transitional and turbulent flow. One needs therefore a detection procedure only able to detect particular frequency components but also to localize the investigated event in time. The wavelet analysis fulfills the above requirements and that is why it was chosen as the detection procedure for the present research.

PL

Artykuł poświęcony jest analizie procesu przejścia laminarno-turbulentnego w warstwie przyściennej na powierzchni wypukłej łopatki turbinowej. Cechą charakterystyczną procesu przejścia jest powstawanie i rozwój pojedynczych struktur cechujących się dużą turbulencją, nazywanych turbulentnymi spotami. Jednym z problemów występujących w analizie warstwy przyściennej jest trudność w odróżnieniu spotów turbulentnych, losowo pojawiających się w czasie i w przestrzeni, od silnie nieustalonego tła przepływu zewnętrznego. Konieczne jest więc opracowanie wiarygodnej procedury detekcji, która nie tylko umożliwi wykrycie charakterystycznych składowych częstotliwościowych, ale również pozwoli lokalizować badane "zdarzenia" w czasie. Wymagania te spełnia analiza falkowa i dlatego została ona wybrana jako podstawowe narzędzie w procesie detekcji spotów.

18

Unsteady Boundary Layer Transition and its Role in Turbomachinery Aerodynamics

Elsner W., Drobniak S.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2005

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nr 128, vol. 1

179-186

EN

Nowadays, the research interest in the modeling near wall region in turbomachinery flows is directed towards boundary layers which are not fully turbulent but laminar and transitional, especially under the condition of wake unsteadiness. The paper presents the review of recent achievements in interpretation of by-pass and wake induced transition processes and the most important aspects of transition modeling. This review is complemented by physical explanation of those phenomena based on the latest literature data as well as on the results of numerical and experimental investigations performed at the Institute of Thermal Machinery.

19

Techniczne i ekonomiczne aspekty rozwoju energetyki w perspektywie dziesięciolecia

Drobniak S., Elsner W.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

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2004

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Vol. 295, z. 53

151-162

PL

Sektor energetyczny oczekuje w najbliższej przyszłości istotna transformacja i przejście od scentralizowanej struktury zorientowanej na proces wytwarzania, do struktury rozproszonej zorientowanej na odbiorców energii. Powstały w ten sposób układ rozproszonej generacji energii zawierający wiele zróżnicowanych źródeł mocy elektrycznej i ciepła, zintegrowany być musi jednak z istniejącym systemem energetycznym. Niezbędne w tym celu będą nowe narzędzia i metody optymalizacji, które pozwolą uzyskać maksymalny efekt ekonomiczny i ekologiczny. Przyjęcie takiej strategii sprawi, że w układzie energetycznym pojawią się duże, wirtualne źródła energii elektrycznej, ciepła i chłodu utworzone z dużej liczby małych jednostek, rozproszonych na dużym obszarze. Przedstawiony w niniejszym artykule przegląd tendencji światowego rynku energii wykazuje istnienie stymulatorów popytowych, technologicznych i ekonomicznych sprzyjających takiej transformacji systemu energetycznego.

EN

The energy sector of the world economy is currently being subjected to a shift from generation-oriented centralised structure to a consumer-oriented, economically and environmentally optimised decentralised network of small regeneration and trigeneration units. The structure of the decentralised generation system must be integrated into a complex structure incorporating a variety of possible energy sources, equipped with controlled local optimisation tools. As a result, a novel intelligent energy supply system will offer the full economical benefit of highly efficient energy sources mixed with renewable energy units. The use of the most updated information and communication technology will enable the creation of virtually large generation units, despite their possible distribution as small units over a wide area. Analysis of current trends of the market reveals the existence of demand, technological and economic drivers for micro-scale or even household - sized power plants The big issue is what technology will be able to produce reliable, emission-free power in distributed networks at a competitive cost, but the technology review presented in the paper provides at least several possible choices of competitive technical solution.

20

ERCOFTAC special interest group #38 on microfluidics and micro heat transfer : the report on the kick-off meeting

Favre-Marinet M., Steenhoven van A., Drobniak S., Asendrych D.

Turbulence : international journal

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2004

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Vol. 10

59-65