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EN
The article considers the methodological aspects of the theoretical investigation of marine power plants with thermochemical fuel treatment. The results of the study of the complex influence of temperature, pressure, and the ratio of steam / base fuel on the thermochemical treatment efficiency are presented. The adequacy of the obtained regression dependences was confirmed by the physical modelling of thermochemical fuel treatment processes. For a gas turbine power complex with a thermochemical fuel treatment system, the characteristics of the power equipment were determined separately with further merging of the obtained results and a combination of material and energy flow models. Algorithms, which provide settings for the mathematical models of structural and functional blocks, the optimisation of thermochemical energy transformations, and verification of developed models according to the indicators of existing gas turbine engines, were created. The influence of mechanical energy consumption during the organisation of thermochemical processing of fuel on the efficiency of thermochemical recuperation is analysed.
EN
The article presents problems occurring during the signals processing of the parameters of working processes of internal combustion engines in tests, while powering the measuring apparatus from the electric network of the marine power plant laboratory. Various experimental methods of separation were used to identify and then eliminate interference. On the basis of analyses carried out in the domain of time and frequency of the in-cylinders pressure signals of internal combustion engines and their wavelet decomposition, attempts were made to determine and eliminate the sources of interference. It has been shown that interference was penetrating the measuring equipment through the supply network. The developed methods of reducing interference in the laboratory conditions can be applied on the marine vessels. On the basis of the conducted tests, it can be concluded that the reduction of interference of pressure measurement signals in the engine cylinder is most effective when the computer is powered only from the battery while the measuring circuit is powered directly from the power network.
PL
W artykule przedstawiono problemy występujące w czasie przetwarzania sygnałów parametrów procesów roboczych w badaniach silników spalinowych, przy zasilaniu aparatury pomiarowej z sieci elektrycznej laboratorium siłowni okrętowej. Dla identyfikacji i następnie eliminacji zakłóceń zastosowano różne eksperymentalne metody ich separacji. Na podstawie wykonanych analiz w dziedzinie czasu i częstotliwości sygnałów ciśnienia w cylindrach silników spalinowych oraz ich dekompozycji falkowych próbowano ustalić źródła zakłóceń oraz je eliminować. Wykazano, że zakłócenia przedostają się do aparatury pomiarowej przez sieć zasilającą. Wypracowane sposoby redukcji zakłóceń w warunkach laboratoryjnych mogą być zastosowane na statkach morskich. Na podstawie przeprowadzonych badań można stwierdzić, że redukcja zakłóceń sygnałów pomiarowych ciśnienia w cylindrze silnika jest najskuteczniejsza, gdy komputer zasilany jest tylko z baterii, a tor pomiarowy bezpośrednio z sieci elektroenergetycznej.
EN
This article presents some of the problems which occur in the course of transforming signals of work process parameters in the testing of internal combustion engines, when power is supplied to a measuring appliance from a shipboard system under certain conditions and on the same measuring path. It characterizes the interference which has an influence on the results of measurements of pressure course in a diagnostics test conducted under marine conditions. In order to identify and to eliminate interference the wavelet analysis of signals of pressure in cylinders of internal combustion engines was carried out. As a result of the analyses it was found that the sources of interference are: electricity grid, electrical power equipment, indicator channels and valves, as well as sensors and measuring sets.
PL
W artykule przedstawiono problemy występujące w czasie przetwarzania sygnałów parametrów procesów roboczych w trakcie badań silników spalinowych, przy zasilaniu aparatury pomiarowej z sieci okrętowej, w określonych warunkach i tym samym torze pomiarowym. Scharakteryzowano zakłócenia mające wpływ na wyniki pomiarów przebiegu ciśnienia w badaniach diagnostycznych prowadzonych w warunkach eksploatacji statków morskich. W celu identyfikacji, a następnie eliminacji zakłóceń zastosowano analizę falkową sygnałów ciśnienia w cylindrach silników spalinowych. W wyniku wykonanych analiz przebiegów czasowych i widmowych oraz ich dekompozycji falkowych ustalono, że źródłem zakłóceń są: sieć zasilająca i urządzenia energetyczne, kanały i zawory indykatorowe oraz czujniki i układy pomiarowe.
PL
W artykule przedstawiono wstępną koncepcję badań dotyczących systemu transportu pneumatycznego paliwa stałego do kotła w warunkach morskich. Uzasadniono konieczność prowadzenia badań w aspekcie sytuacji energetycznej na świecie i możliwości wykorzystania alternatywnych paliw dla statków, także stałych, takich jak węgiel czy biomasa stała. Zawarto też przegląd rozwiązań instalacji transportu pneumatycznego oraz koncepcję budowy stanowiska badawczego wraz z planem pomiarów.
EN
This article presents an initial concept of investigations on a pneumatic transportation system of solid fuel to a boiler in marine conditions. It justifies the necessity to carry out investigations in the aspect of the worldwide energy situation and the possibilities of using alternative fuels in ships, including solid ones, such as coal or biomass. It also includes a review of solutions used in pneumatic transport installations as well as a concept of building a research stand together with a plan of measurements.
EN
Packaging and thermal management of electronic equipment that are located i.e. in a novel marine power plants or computer server rooms has led to the demand for new and reliable methods for electronic cooling. Because of bigger and bigger power levels and miniaturization of the electronic devices, lack of free space in marine power plant, typical cooling techniques such as conduction and forced convection are not able to cool such a high heat flux. The increasing integration of electronic systems requires an improved cooling technology that supposed to be designed for high thermal performance, low mass, and able to work in harsh environments. In this paper presented a prototype of thermosiphon loop heat exchanger developed in Institute of Energy and Industrial Processes in Gdansk University of Technology. This thermosyphon loop is heated from below horizontal side and cooled from upper horizontal side, the working fluid that circulate inside the loop is acetone.
EN
The article presents the general description of the waste energy recovery systems in the marine Diesel power plants. Both, the simple as well as the complex recovery systems have been discussed. The substantial part of the article concerns the overview of the evaluation methods of the recovery systems arrangements. There have been presented the rudiments of the thermodynamic evaluation which in the effect provides the material for the determination of the energetic and exergetic efficiency of the recovery systems. The significant issue is also the description of the method of the arrangements economic evaluation, including the method of the determination of the annual profit ensuing from the operation of the waste energy recovery system and the dynamic methods of the economic analysis with the particular emphasis on the investment outlay payback period index. There have been presented the examples of the dependence of the waste heat turbo-generators on the main engine power output, the estimated payback times of the investment outlays incurred in connection with the discussed systems and the payback time of the outlays with reference to the main engine power output in the function of its power output.
EN
Growing costs of ship operation and actions taken to reduce the emission of harmful components in exhaust gases make designers seek more effective methods of utilizing substantial amounts of waste energy in marine power plants. One such method leads to the steam turbogenerator. This machine to run, however, requires substantially greater amount of steam generated in the waste heat boiler (compared to steam demand for heating purposes). It is possible to supply a sufficient amount of steam if the waste heat contained in exhausts and charge air of the main engine is fully utilized. This article analyzes the influence of some methods of using waste heat from exhaust gases and charge air on the amount of steam produced in the waste heat boiler. The analysis takes account of boundary conditions, such as steam pressure in the boiler and the minimum value of outlet gas after the boiler. The analysis is illustrated with examples of basic calculations for the waste heat boiler co-operating with a specific slow speed engine. Two variants of waste heat recovery installation solutions are considered.
PL
Rosnące koszty eksploatacji statków oraz działania związane z ograniczeniem emisji szkodliwych składników spalin skłaniają konstruktorów do wnikliwych analiz możliwości skuteczniejszego wykorzystania zasobów energii odpadowej w siłowniach okrętowych. Jedną z nich jest zastosowanie turboprądnicy parowej. W tym celu należy znacząco (w porównaniu z zapotrzebowaniem pary na cele grzewcze) zwiększyć ilość pary wytworzonej w kotle utylizacyjnym. Jest to możliwe przy pełnym wykorzystaniu ciepła odpadowego zawartego w spalinach i w powietrzu doładowania silnika napędu głównego. W artykule przedstawiono analizę wpływu wybranych sposobów wykorzystania ciepła spalin i powietrza doładowania na ilość pary wytworzonej w kotle utylizacyjnym z uwzględnieniem warunków brzegowych, takich jak ciśnienie pary w kotle oraz minimalna wartość temperatury spalin za kotłem. Analizę zobrazowano przykładami podstawowych obliczeń dla kotła utylizacyjnego współpracującego z wybranym typem silnika wolnoobrotowego w dwóch wariantach rozwiązań instalacji utylizacji ciepła odpadowego.
EN
A general characteristic of power fluctuation as the casual discrete phenomena in marine power plants have been considered. The approach to processing of the statistical information necessary for a substantiation of a technique of voltage failures’ statistical research is offered. The software for the statistical analysis of processes power change and definition of a power station operating mode are developed.
PL
Artykuł omawia ogólną charakterystykę wahań zasilania jako przypadkowych, dyskretnych zjawisk w morskich siłowniach okrętowych. Zaproponowano sposób przetwarzania informacji statystycznych niezbędnych do uzasadnienia techniki badania statystycznego awarii napięcia. Opracowano oprogramowanie do analizy statystycznej procesów zmiany zasilania i definicję trybu pracy siłowni.
EN
Growing environmental protection requirements also include problems of ozone depletion by coolants. This article presents a possibility of using a cause-and-effect diagram, known as Ishikawa diagram, for an analysis of faults occurring in marine refrigeration systems. The analysis, focused on refrigeration systems installed in Polish fishing vessels, makes use of extensive faults data collected during research.
EN
The waste energy utilisation degree in the marine Diesel power plants grows as the exhaust gas boiler exhaust gas temperature decreases. The limitation in this case is not only a likelihood of sulphur corrosion occurrence in the boiler and exhaust gas ducts, but also the obtainment of too little, or altogether negative values of so called pinch point. The article presents the analysis of the limitations related with the pinch point and minimum boiler exhaust gas temperature which are possible for the acceptance at the stage of the preliminary design in terms of the system correct operation and its energetic effectiveness. The possible negative results of the exhaust gas boiler exhaust gas temperature reduction and the methods to prevent the results have been presented. In the effect of conducting the calculations for the selected thermodynamic parameters of a model waste energy recovery system there has been presented the graphic course of the changes in the achieved power of the steam turbine generator and the pinch point in exhaust gas boiler in relation to the boiler exhaust gas temperature, the generated steam pressure, recovery system feedwater temperature and the main engine exhaust gas temperature. The data presented in the article are but of general nature and reflect the relations between the selected thermodynamic parameters that characterise the model of the waste energy recovery system in the marine Diesel power plant.
EN
The paper presents simulation calculations for a ship’s power transmission system and the associated exhaust gas boiler with the aim of assessing the boiler’s efficacy. Increasing prices of marine fuels force ship owners to limit the cruising speed of ships. This has negative impact on the operation of an exhaust gas boiler powered with exhaust fumes from the main engine. The boiler’s capacity decreases, seriously limiting the tasks ascribed to vapour. Simulation calculations were conducted for the most typical system used on sea ships, i.e. a multi-turn engine and the associated exhaust gas boiler which generates saturated vapour. Adopting several values of ship cruising speed, which were smaller than the nominal speed, was a starting point for he calculations. Main engine powers were calculated with partial loads. Next, relevant values of excess air number were assigned to those powers and classic combustion calculations were conducted with the use of stochiometric combustion equations. For assumed fumes temperatures in front of and behind the boiler drops in fumes enthalpy were noted. It enabled to calculate the values of heat fluxes released by the fumes in the boiler. After adopting relevant vapour parameters boiler capacities were evaluated as appropriate. Results of those calculations are shown in tables and on the graphs. The summary of the paper includes conclusions and suggestions which may be helpful as far as designing waste heat recovery systems is concerned.
EN
The article presents the operational and economic analysis of controlling the cooling water flow in marine steam turbine power plants. The analysis bases on selected designs of the main condenser cooling water pumps and makes use of the results of investigations performed in inland power plants. Special attention was focused on marine aspects of the operation of those systems.
EN
The article compares combined systems in naval applications. The object of the analysis is the combined gas turbine/steam turbine system which is compared to the combined marine low-speed Diesel engine/steam turbine system. The comparison refers to the additional power and efficiency increase resulting from the use of the heat in the exhaust gas leaving the piston engine or the gas turbine. In the analysis a number of types of gas turbines with different exhaust gas temperatures and two large-power low-speed piston engines have been taken into account. The comparison bases on the assumption about comparable power ranges of the main engine.
EN
The article presents a concept of a combined large-power ship propulsion system, composed of the leading internal combustion main engine associated with a power gas turbine and the steam turbine system, both utilising the energy taken from the main engine exhaust gas. In the examined variant the power turbine, arranged in parallel with a turbocharger, is fed with the exhaust gas from the exhaust manifold. A calculation algorithm is presented, along with sample calculations for particular subsystems: supercharging, gas power turbine, and steam turbine system. Assumptions were formulated for the calculations, and were complemented by the adopted limits. Selected system parameters were confronted with the experimental investigations available in the literature. The performed power optimisation of the entire combined marine power plant took only into account the thermodynamic point of view, leaving aside technical and economic aspects. The numerical calculations were performed for the 52 MW low-speed marine diesel engine.
EN
The paper presents a proposal of the application of the entropy analysis for the theoretical research of the processes occurring during the thermodynamic transformations taking place in the waste energy recovery systems in marine Diesel power plants. In view of the low exergy of waste energy carriers in these systems it becomes significant to make a proper selection of parameters in the individual points characterising the thermodynamic transformations of the working media. The method as presented herein consists an adaptation of the methods applied in the arrangements of shore power plants to the needs of the marine power plants. This article presents basic relations allowing to determine increments in entropy in the heating steam generation system, as well as the other basic elements forming the waste energy recovery systems in marine power plants. They constitute the basis to evaluate the performance of the individual processes and to disclose the places of occurrence of the major losses and to determine the manners to minimise same. The proposed method may contribute to the reduction of labour consumption of universally applied, traditional methods of searching the effective systems of waste energy recovery in marine Diesel power plants.
PL
Ograniczona dostępność pomiarowa sygnałów generowanych podczas pracy zautomatyzowanych kotłów pomocniczych zmusza do wykorzystywania w procesie tak modelowania jak i rzeczywistego dozorowania stanów kotłów na podstawie wybranych sygnałów odwzorowujących stan techniczny kotłów. Przeprowadzono dekompozycję strukturalną i funkcjonalną okrętowego pomocniczego kotła parowego. Sygnały podzielono na: cieplno-przepływowe, emisji toksycznych zanieczyszczeń w strumieniu spalin wylotowych, jak również wibroakustyczne. Przedstawiono estymację parametrów sygnałów na podstawie wyników pomiarów wielkości wyjściowych ogólnego modelu kotła. W pracy zdefiniowano sygnały tworzące relacje diagnostyczne, jakich można oczekiwać w procesie oceny stanów kotłów okrętowych. Ich identyfikacja może być uzasadnieniem do wdrożenia strategii eksploatacji kotłów okrętowych z tzw. obsługiwaniem quasidynamicznym
EN
The especially limited measurement availability of signals generated at operation of automated auxiliary boilers enforces the application of modeling as well as actual monitoring of their condition on the basis of a significant number of reliable measurement signals. A structural and functional decomposition of an auxiliary ship boiler has been carried out. Signals have been divided into: thermal-flow, exhaust toxic pollutant emissions in gas flows of marine boilers, as well vibroacoustic and acoustic. Estimation of signals parameters, basing on the results of measurements of output values for a general boiler model, has been suggested. Diagnostic relations which can be expected to be valid for ship boilers have been defined. Establishing their validity may be a justification for implementing a ship boiler quasidynamic maintenance.
EN
The efficient use of waste energy is a major element in designing the energy-saving marine power plants. The ecological aspects of the usage of this energy are of importance as well. Thus the need to perform the evaluation becomes significant – in respect of both the sources of the waste energy and the marine systems of its recovery, inter alia in terms the achievable efficiency levels. Besides the determination of the available quantity of the energy it is necessary to take into account the value characterising this energy in terms of its quality. The measure of the quality of the energy is the value of the maximum capacity of work performance referred to as the exergy. The exergetic analysis allows to determine the values of the individual jets of working media as well as, which is particularly important, allows to properly assess the proportions of losses in the individual elements of the recovery systems under investigation. Therefore it is a basis to calculate their exergetic efficiency. The article presents the balance values of the energy fluxes of the selected ship’s main propulsion engines as well as, inter alia an example of the course of the changes in the specific exergy and enthalpy of the exhaust gases in the function of the load of ship’s main propulsion engine. It presents also the examples of the exergetic analysis of the main propulsion engine exhaust gases recovery systems with the application of Brayton cycle, Clausius-Rankine cycle or both cycles combined.
EN
In the paper there has been presented a method of assessing auxiliary engines load based on identification tests of marine electric power systems loads of cargo vessels. The analysis has been illustrated by means of four auxiliary engines of an up-to date container ship 2200 TEU. A critical analysis of adjusting the auxiliary engines excess power factor to the active rated power of the generators of the currently operating generating sets.
PL
Stały wzrost zapotrzebowania na handel morski spowodował silny rozwój floty kontenerowców. Wielkość światowej floty kontenerowców wynosiła 3400jednostek w marcu 2005 a zaledwie rok później osiągnęła ona wartość około 3800 jednostek. Co więcej, światowa lista zamówień na kontenerowce zawiera ponad 1000 jednostek. Liczba największych kontenerowców rośnie zgodnie z liczbą pływających po morzu kontenerowców. Przewidywalny jest wzrost zapotrzebowania na małe statki dostawcze i statki dostawcze z większą pojemnością handlową, oznaczającą większą liczbę TEU na pokładzie i większą prędkością rejsową, wzrost wynikający z większej liczby kontenerowców o dużych pojemnościach zawijających do kilku głównych portów morskich. Te małe statki dostawcze i statki dostawcze zapewnią handel pomiędzy dużymi terminalami kontenerowymi i małymi portami spełniając funkcje zaopatrzeniowe. Współczesne statki kontenerowe mają pojemność ładunku dochodzącą do 14 000 TEU i przewiduje się, że pojemność ta osiągnie wartość 18 000 TEU z prędkością podróżną wynoszącą 28 węzłów. Powoduje to konieczność wykorzystania jako głównych silników statków silników Diesla o mocach wyjściowych dochodzących do 100 000 kW ze sprawnością około 50%. Artykuł zawiera klasyfikację floty kontenerowców opartą na liczbie TEU i obszarze żeglugowym, jak również zawiera opisy konfiguracji morskich siłowni dla współczesnych kontenerowców, z uwzględnieniem napędu głównego, siłowni elektrycznych i parowych. Ponadto, omówione zostały współczesne trendy w budowie kadłubów okrętowych i morskich siłowni.
EN
Permanent growth of sea trade demand has contributed to strong expansion of container carriers. The capacity of the worlds container fleet was about 3400 vessels in March 2005 and only one year later it reached the number of about 3800 ships. What is more, there are over 1000 container carriers in the world's order book. The number of the biggest capacity container carriers is growing along with the number of container vessels at sea. The increasing demand for small feeders and feeders with higher trade capacity, meaning more TEU on board and higher en route speed resulting from higher number of large capacity container carriers that will call at a few main seaports, is predictable. These small feeders and feeders will trade between big container terminals and smaller ports as suppliers. Contemporary container vessels have a load carrying capacity of up to 14 000 TEU and it is foreseen that the capacity will reach 18 000 TEU with voyage speed amounting to 28 knots. It causes the necessity of using diesel engines whose output power is even 100000 kW with an efficiency of about 50% as the main ship propulsion. The container vessel fleet classification based on TEU number and trading area as well as configurations of marine power plants for the contemporary container vessels regarding main propulsion, electric power and boiler plants have been shown in the article. Moreover, the trends of ship hulls and marine power plants are discussed.
EN
There has been presented a new procedure of the seating of a combustion engines at the marine power plant with steel chocks cemented by a thixotropic polymer composition between the engine's spot footing and the foundation ledge. A combustion engine is seated on foundation at the marine power plant by steel chocks or the chocks that are cast from polymer composition at the marine power plant. The arrangement, number and dimensions of foundation chocks, as well as arrangement, number and dimensions of the lateral and frontal stoppers that secure chocks work, are established by an engine manufacturer and are approved by Classification Society that supervises the vessel's construction and operation. The author's intention was to develop such chocks that combine the good resistance of steel chocks with the easiness of adjustment the bearing surfaces of polymer compositions chocks. Combination of these features was obtained for steel chocks which are glued by the relatively thin layers of polymer compositions between the engine spot footing and the foundation ledges. Such a method of making the chocks and seating with them the engines on foundation was claimed with the Patent RP No. 192120 on 24th July 2000 for the Polish Naval Academy. In order to receive the approval of the Polish Register of Shipping to use new chocks at the marine power plants, the author carried out appropriate research, results of which are presented below. The results obtained in the research show that by seating of a combustion engine with these steel-thixotropic polymer chocks at the marine power plant, the foundation bolts tension can be diminished to the value equal to five times of the engine weight.
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