Ship Power Plant Research Articles

ИССЛЕДОВАНИЕ ВОЗМОЖНОСТИ ПРИМЕНЕНИЯ ПАРОГАЗОВЫХ УСТАНОВОК НА СУДАХ РОССИЙСКОГО ФЛОТА

The article studies the possibility of application combined-cycle gas turbine plants (CCGT) in the Russian Navy. A review of numerous publications allows to infer that the essential increase of ship power plant (SPP) efficiency (10-15%) can be reached by using combine-cycle gas turbine plants. It should be noted that the greatest effect on CCGT performance makes the level of technological sophistication of gas-turbine units (GTU), in particular, the gas temperature achieved before the turbine. The possibility of creating marine CCGT in Russia is being explored. The article contains examples of the use of GTUs on board foreign ships. Close attention is drawn to the advanced techniques used to increase CCGT efficiency. There have been presented calculations of the approved scheme of CCGT, which demonstrate the advantages of using CCGTs.

КОНСТРУКЦИЯ И РАСЧЕТ ТЕРМОЭЛЕКТРИЧЕСКОГО ГЕНЕРАТОРА ДЛЯ СУДОВЫХ ЭНЕРГЕТИЧЕСКИХ УСТАНОВОК

The article presents the design of a thermoelectric generator (TEG) for utilizing heat energy of exhaust gases of ship diesel engines. There have been chosen a TEG basic design and a technique for its efficiency raising. Geometric, heat and electric parameters of TEG have been calculated using RSD 49 ship project. Calculation of heat and electric parameters of TEG with intensive heat exchange on the surface of a hot node was made using sloping plates. The relation between TEG position (before and after exhaust boiler) and a Wartsila 6L20 main engine exhaust system has been determined. According to the analysis result, in case of TEG position after exhaust boiler and 100% load of main engine, estimates increased compared to a basic design: performance - 4%, capacity - 5%; output gas temperature decreased to 1%. At combined operation of TEGs positioned in the exhaust system of one main engine with exhaust boiler shut down and TEG positioned after exhaust boiler, estimates grew: capacity - 35%, performance - 14%; output gas temperature decreased to 19%. Total maximum capacity of TEGs positioned in the main engine exhaust systems makes 42.78 kW which is 1.78% of a ship power plant capacity.

About some peculiarities of calculating the energy flow in the non – equilibrium diesel engine cycle

In the modern methods of calculating the reciprocating engines there is an assumption that the ideal gas is used as actuation fluid in the cycle that makes the current task much easier however brings sufficient untrueness to the achieved results and mispresents the description of the process itself. It was suggested an algorithm of calculating the thermodynamic cycle through releasing the equilibrium component of the energy flow in the non-equilibrium combined cycle at the cost of accepted concept of the process volume speed as a cycle parameter. The developed method allows to separate the most efficient cycle part and after achieving in the remaining part of energy can be used for ship power plant operation by means of effectively set phase of releasing the exhaust gases.

Assessment of destabilizing factor for automatic control systems in propulsion systems of mechatronic and maritime transport objects

It is known that many of today’s ships and vessels have a shaft generator as a part of their power plants. Modern automatic control systems used in the world’s fleet do not enable their shaft generators to operate in parallel with the main diesel generators for long-term sustenance of the total load of the ship network. On the other hand, according to our calculations and experiments, a shaft generator operated in parallel with the main power plant helps save at least 10% of fuel while making the power system of the ship more efficient, reliable, and eco-friendly.The fouling and corrosion of the propeller as well as the weather conditions of navigation affect its modulus of resistance. It changes the free component of the transient process of shaft generator stress frequency changes in transient processes. While the shaft generator and the diesel generator of the ship power plant are paralleled, there emerges an angle between their EMF. This results in equalizing currents generated between them. The altering torque in the drive–shaft line—propeller system causes torsional fluctuations of the ship shaft line. To compensate for the effect of destabilizing factors and torsional fluctuations of the shaft line on the dynamic characteristics of the transient process that alters the RPM of the main engine, sliding mode controls can be used. To synthesize such a control, one has to evaluate the effect of destabilizing factors.

Theoretical-applied aspects of the composition of regression models for combined propulsion complexes based on data of experimental research

Based on the study into internal properties of components of the ship power plants (SPP) in the combined propulsion complexes (CPC) and considering special features in the construction of equations that characterize energy processes in the specific SPP of the particular CPC, we developed the principles of constructing their regression models according to data from experimental research. The function is defined that connects input variables and the output variable based on data of the experiment with the certain number of common observations of the input and output parameters. The check for adequacy of the obtained model was performed according to the experimental data. Such studies are necessary in order to develop specialized software modeling tools that are used when designing CPC SPP whose structure may vary in certain specified operational limits and situational factors. Similar empirical models also make it possible to improve simulation modeling algorithms involving the use of statistical tests and construction of CPC SPP models based on experimental data. As the result of present research, according to data obtained in the course of experiment, which contained 14 joint observations of the input and output parametric coordinates of the thruster drives (TDs) of CPC of the ship that operates under dynamic positioning mode, we estimated variation in the coefficients of regression equation and determined coefficients b 0 =0.4527; b 1 =–0.1126; b 2 =0.0848; b 3 =–0.0277; b 4 =0.0856, which refine the structure of regression model of SPP of CPC. For different levels of significance and degrees of freedom, the Student's t-criterion was computed for significance level α=0.06 and for the number of degrees of freedom 30 f y =30t(0.06; 30)=t(0.06; 2)=4.823, as well as the Fisher’s F-criterion F e (0.06; 12; 2)=5.43, on the basis of which the conclusion was made that confirms adequacy of the obtained model according to the experimental tests. Based on the constructed regression model, it is possible to adjust the position of CPC TD relative to each other and to the diametrical plane of the ship, as well as directions of TD rotation in the process of optimization of parameters of physical models of control systems of TD electric engines.

Formalization of design for physical model of the azimuth thruster with two degrees of freedom by computational fluid dynamics methods

Based on theoretical and practical studies into the causes of losses of propellers, caused by the axial inflows, employing the methods of computational fluid dynamics, we calculated the geometry of physical model of the thrusters with two degrees of freedom. We specified the required physical conditions of implementation, formalized geometric parameters of the model, assigned the initial and boundary conditions of differential equations that describe behavior of propeller flows in the recirculation zones. The coefficients are calculated that take into account the existence of degradation effects. The use of methods of computational fluid dynamics is necessary to account for the losses of propellers caused by the axial water inflows that are dependent on the degradation effects, which will contribute to reducing the propeller thrust and torque. As the result of the studies, we received the Reynolds and Froude numbers for the zero-velocity model of the ship: R n =4.405×106; F r =3.124. Components of the axial and tangential forces of the radial distribution of steering propellers thrusts are refined within the limits of 2.7–5.1 %. The largest deviation of similarity coefficients is in the region of 85–100 % of the rated propeller thrust. We obtained dependences of adjustment factors that affect the components of thrusts and torques proportional to the radius of propeller of the model and the actual steering propeller, related to the original geometry. The value of corrective factors depending on the propeller flow direction relative to the plane of motion of the ship is within the few hundredths of the percent. We systematized and compiled in the table the list of parameters (factors) according to the operating mode of the ship, which are required to solve the basic equations in the formalization of physical models of thrusters. The developed principles of formalization of the physical models of thrusters could be employed in the process of selection and improvement of design of combined propulsive complex and adjustment of selected regulators of components of the ship power plant.

DESIGN OF THE THREE-LEVEL MULTICRITERIAL STRATEGY OF HYBRID MARINE POWER PLANT CONTROL FOR A COMBINED PROPULSION COMPLEX

Purpose. Efficiency of hybrid ships power plants (SPP) combined propulsion complexes (CPC) by various criteria for energy management systems strategies . Methodology. Based on the classification system topologies SPP CPC for mechanical, electrical and hybrid types of motors schematic diagrams of management strategies for the criterion of minimum power consumption are defined. Changing the technical component of the traditional approach to building hybrid ships electric power systems (SEPS) SPP CPC the principle of modifying the structure of SEPS is applied with the integration of additional static alternative power source as dynamic reserve, which allowed to meet modern requirements for energy efficiency, levels of vibration, noise and degradation effects produced to SPP CPC, in all areas of the energy for the transfer of power from energy to propellers. Modeling of power transmission of energy to propellers in MatLab/Simulink is conducted, using blocks of optimization library and definition of identity markers. Results. Major advantages and disadvantages SPP CPC depending on the topology of energy distribution systems are determined. According to the chosen structure system electricity characteristics were obtained in the process of power transmission SPP CPC and power systems and their control strategies in terms of increased efficiency and eliminate these drawbacks. And finally, mathematical apparatus for research in terms of the development of methods for designing and managing SPP hybrid CPC to reduced fuel consumption, emissions into the environment and improving maintainability, flexibility and comfort level are improved. Originality. The methodology for improving SPP CPC implementation by developing methods of identification markers mutually influencing processes in SPP CPC and the development of implementing these methods of settlement and information systems. Practical value. The method enables iterative optimization parameters SPP CPC, it can be used as a means of intelligent design, which is the result of the application of improved performance SPP CPC.

ПОВЫШЕНИе УСТОЙЧИВОСТИ К ДЕСТАБИЛИЗИРУЮЩИМ ФАКТОРАМ ЭНЕРГЕТИЧЕСКОЙ УСТАНОВКИ ПРОМЫСЛОВОГО СУДНА

The task of developing methods and tools for the study of stability for parallel operation of two or more diesel and the shaft generator sets as a part of an autonomous electrical power system of the fishing vessel is considered. The use of such devices is a promising and demanded, but difficult to implement due to the high dependence of the frequency of the current generated by such units on the temperature and the quality of lubricating oils, advance angle of fuel supply, the depreciation of the fuel equipment, the influence of depreciation of cylinder piston group and parts of the crank mechanism, the load, the fuel properties and the external environment. The method of increasing the stabilization of processes in the units of the ship power plants and providing their rating data in the conditions of availability of the destabilizing operational factors is offered. The method is based on the compensation of influence of the destabilizing operational factors on dynamic characteristics of transition processes on the frequency of ship power plant units. The modeling results are presented in the example of implementation of described approach. The scheme of the regulator of the sliding mode of the adaptive system of automatic control with the frequency of rotation of a bent shaft of diesel allowing to study the processes of fluctuations of its speed and to develop the principles of its effective management was developed. For its synthesis the new mathematical description of dynamics of diesel which brings the generator into rotation was developed. This allows not only to provide the work of diesel and the shaft generators units, but also, as a result, to exercise effective management of electric power parameters in autonomous electric power industry, to develop means and methods of providing the required indicators of quality of the electric power produced by the main and auxiliary power units.

Overview of training programs for midshipmen in the usa

The international maritime community systematically introduces ever higher standards of quality training of marine specialists capable of professional growth and rapid conversion for the operation of modern vessels of all types. At the heart of 84 % of emergency cases are errors due to insufficient competence of specialists, managers of the ship and operating ship power plants and systems. The basic level of training is reduced, seafarers lack practical skills. To remain a maritime power, competitive in the training of qualified specialists at all levels, manage the modern fleet and effectively operate it, it is necessary to improve the system of maritime education without delay. The work provides an overview of training programs for midshipmen in the United States.

MODELING OF OPERATION MODES OF SHIP POWER PLANT OF COMBINED PROPULSION COMPLEX WITH CONTROL SYSTEM BASED ON ELECTRONIC CONTROLLERS

Purpose. Designing of diagrams to optimize mathematic model of the ship power plant (SPP) combined propulsion complexes (CPC) for decreasing operational loss and increasing fuel efficiency with simultaneous load limiting on medium revolutions diesel generator (MRDG) by criterion reducing of wear and increasing operation time between repairs. Methodology. After analyzing of ship power plant modes of CPC proposed diagrams to optimize mathematic model of the above mentioned complex. The model based on using of electronic controllers in automatic regulation and control systems for diesel and thruster which allow to actualize more complicated control algorithm with viewpoint of increasing working efficiency of ship power plant at normal and emergency modes. Results. Determined suitability of comparative computer modeling in MatLab Simulink for building of imitation model objects based on it block diagrams and mathematic descriptions. Actualized diagrams to optimize mathematic model of the ship’s power plant (SPP) combined propulsion complexes (CPC) with Azipod system in MatLab Simulink software package Ships_CPC for decreasing operational loss and increasing fuel efficiency with simultaneous load limiting on medium revolutions diesel generator (MRDG) by criterion reducing of wear and increasing operation time between repairs. The function blocks of proposed complex are the main structural units which allow to investigate it normal and emergency modes. Originality. This model represents a set of functional blocks of the components SPP CPC, built on the principle of «input-output». For example, the function boxes outputs of PID-regulators of MRDG depends from set excitation voltage and rotating frequency that in turn depends from power-station load and respond that is a ship moving or dynamically positioning, and come on input (inputs) of thruster rotating frequency PID-regulator models. Practical value. The results of researches planned to use in creation of software package Ships_CPC, in Mat Lab/Simulink was developed under the state budget project «Concepts, technologies and ways of improving ship plants combined propulsion complexes» at the Department of Electromechanics and Electrical Engineering of National University «Odessa Maritime Academy» (State registration number 0114u000340).

Thermal design of a natural gas - diesel dual fuel turbocharged V18 engine for ship propulsion and power plant applications

A detailed method is presented on the thermal design of a natural gas - diesel dual fuel internal combustion engine. An 18 cylinder four stroke turbocharged engine is considered to operate at a maximum speed of 500 rpm for marine and power plant applications. Thermodynamic, heat transfer and fluid flow phenomena are mathematically analyzed to provide a real cycle analysis together with a complete set of calculated operation conditions, power characteristics and engine efficiencies. The method is found to provide results in close agreement to published data for the actual performance of similar engines such as V18 MAN 51/60DF.

Optimal load allocation of complex ship power plants

In a world with increased pressure on reducing fuel consumption and carbon dioxide emissions, the cruise industry is growing in size and impact. In this context, further effort is required for improving the energy efficiency of cruise ship energy systems.In this paper, we propose a generic method for modelling the power plant of an isolated system with mechanical, electric and thermal power demands and for the optimal load allocation of the different components that are able to fulfil the demand.The optimisation problem is presented in the form of a mixed integer linear programming (MINLP) problem, where the number of engines and/or boilers running is represented by the integer variables, while their respective load is represented by the non-integer variables. The individual components are modelled using a combination of first-principle models and polynomial regressions, thus making the system nonlinear.The proposed method is applied to the load-allocation problem of a cruise ship sailing in the Baltic Sea, and used to compare the existing power plant with a hybrid propulsion plant. The results show the benefits brought by using the proposing method, which allow estimating the performance of the hybrid system (for which the load allocation is a non-trivial problem) while also including the contribution of the heat demand. This allows showing that, based on a reference round voyage, up to 3% savings could be achieved by installing the proposed system, compared to the existing one, and that a NPV of 11kUSD could be achieved already 5years after the installation of the system.

Decision support system’s concept for design of combined propulsion complexes

It is shown that there are many mathematical models (MM) of ship power plants for various purposes. Such MM are integrated into decision support systems (DSS) and used in the design and power optimization of ship power plants (SPP) of various constructional configurations. Experimental research and scientific literature analysis prove that such integrated MM into DSS are not always adequate to real physical processes in some modes, for example, dynamic ship positioning. That is why integrated MM SPP into DSS need clarification as well as the existing DSS need further development. The approach for the creation of specialized DSS SPP of the ship combined propulsive complexes (CPC) is proposed, which allows predicting the number and type of thrusters (T), pods, power system, and does not require the application of similarity criteria, allows a multiple analysis of the structure at minimal initial data. The designed DSS applies the principles of the construction of DMI-models ships and methods of implementation of characteristic spatial vectors of power processes, gives a possibility to synthesize recommendations to T designers, controllers and power systems for ships operating in the dynamic positioning modes. Created DSS can be used practically for any type of vessels and adapted for the modes of dynamic ship positioning. It is established for a given rotation speed of the pods, traction, torque and stepper ratio with the help of created DSS, that traction coefficient grows with the change in mutual location of T relative to each another and diametrical plane of the vessel. It is proved that the interelation of thrusts coefficients are correlated better with the power coefficients than with the stepping pods coefficients, allowing increasing energy efficiency of SPP CPC in the dynamic positioning modes. The results of the research can be implemented into data bases of similar DSS and provide researchers with verified information needed for creation of new concepts of SPP CPC design for modification of existing systems.

Analysis of Possible Application of High-Temperature Nuclear Reactors to Contemporary Large-Output Steam Power Plants on Ships

Abstract This paper is aimed at analysis of possible application of helium to cooling high-temperature nuclear reactor to be used for generating steam in contemporary ship steam-turbine power plants of a large output with taking into account in particular variable operational parameters. In the first part of the paper types of contemporary ship power plants are presented. Features of today applied PWR reactors and proposed HTR reactors are discussed. Next, issues of load variability of the ship nuclear power plants, features of the proposed thermal cycles and results of their thermodynamic calculations in variable operational conditions, are presented.

IMPLEMENTATION APPROACHES DURING SIMULATION OF ENERGY PROCESSES FOR A DYNAMICALLY POSITIONED SHIP

Purpose. Creation of a mathematical model of the ship's power plant (SPP) combined propulsion complexes (CPC) that takes into account the behavior of all objects, including the ship itself, the transfer of power from the medium speed diesel generators on the propellers, which will allow to take into account the hydrodynamic properties of the vessel and their impact on the energy processes in SPP CPC. Methodology. The analysis of energy processes in the SPP CPC in different operating conditions resulted in creation of a strategy for constructing mathematical models of SPP CPC. This strategy is based on the implementation on the vector plane resulting power characteristics of SPP vectors disturbances, leading to the deviation of the hydrodynamic characteristics of the ship during operation dynamic positioning. The result allowed to consider not only the features of setting PID-governors of frequency converters of electric thrusters but the automatic voltage regulators of medium speed diesel generators as well. Results. Within the research work a software package Ships_CPC in MatLab/Simulink was developed under the state budget project «Concepts, technologies and ways of improving ship power plants combined propulsion complexes» at the Department of Electromechanics and Electrical Engineering of Odessa National Maritime Academy. Originality. This complex represents a set of functional blocks of the components SPP CPC, built on the principle of «input-output». The simulation results demonstrate the ability to use software package Ships_CPC to study the effect of various settings on the energy regulators of processes SPP CPC, which can develop and integrate the different strategies of automatic voltage regulators. Practical value. Since software complex Ships_CPC was developed under Open system technology, it can reorganize, re-tune and integrate in processes of any difficulties with further completion in the form of a universal structure.

Analysis of Power Installed in Ship Power Plants of Offshore Type Vessels

This paper defines factors determining the values of electrical energy fluxes required by chosen bulk carriers and specialized ships. Relations between these factors and unique specifics of offshore type vessels have been pointed out. Basing on the compiled lists of similar vessels, using regression and determination coefficient, the strength of Pearson’s linear correlation between the total power of the main power system of particular types of ships and the required installed electrical energy was determined. The obtained relations were graphically correlated with each other revealing special qualities significant for the operation of offshore vessels, different than for other types of ships.

Technological limitations and features of burning coal-water slurry fuels in ship power plants

technological limitations and features of burning coal-water slurry fuels in ship power plants

Calculation of Efficiencies of a Ship Power Plant Operating with Waste Heat Recovery through Combined Heat and Power Production

The aim of this research was to investigate the possibility of a combined heat & power (CHP) plant, using the waste heat from a Suezmax-size oil tanker’s main engine, to meet all heating and electricity requirements during navigation. After considering various configurations, a standard propulsion engine operating at maximum efficiency, combined with a supercritical Organic Rankine cycle (ORC) system, was selected to supply the auxiliary power, using R245fa or R123 as the working fluid. The system analysis showed that such a plant can meet all heat and electrical power requirements at full load, with the need to burn only a small amount of supplementary fuel in a heat recovery steam generator (HRSG) when the main engine operates at part load. Therefore, it is possible to increase the overall thermal efficiency of the ship’s power plant by more than 5% when the main engine operates at 65% or more of its specified maximum continuous rating (SMCR).

Thermodynamic and Environmental Analysis of Low-Grade Waste Heat Recovery System for a Ship Power Plant

Shipping is a growing sector in the global economy and its contributions to global greenhouse gas (GHG) emissions are expected to increase. Energy efficiency has always been an important factor to minimize GHG emissions. Waste heat recovery (WHR) systems can be used for both improving energy efficiency and reducing energy consumption and GHG emissions. Organic Rankine Cycles (ORC) systems are the most widely used technology for low temperature heat recovery from exhaust gases in the industrial applications. But this system is not widely used in ship applications. In this study thermodynamic performance criteria of ORC system for a container ship are developed and thermodynamic, environmental and economic effects of the system are analyzed. It can be achieved additionally 2% reduction for the ship fuel consumption by utilizing the ORC system.

Thermodynamic Analysis of a Ship Power Plant Operating with Waste Heat Recovery through Combined Heat and Power Production

The goal of this research is to study a cogeneration plant for combined heat & power (CHP) production that utilises the low-temperature waste energy in the power plant of a Suezmax-size oil tanker for all heating and electricity requirements during navigation. After considering various configurations, a standard propulsion engine operating at maximum efficiency and a CHP Plant with R245fa fluid using a supercritical organic Rankine cycle (ORC) is selected. All the ship heat requirements can be covered by energy of organic fluid after expansion in the turbine, except feeder-booster heating. Hence, an additional quantity of working fluid may be heated using an after Heat Recovery Steam Generator (HRSG) directed to the feeder-booster module. An analysis of the obtained results shows that the steam turbine plant does not yield significant fuel savings. However, a CHP plant with R245fa fluid using supercritical ORC meets all of the demands for electrical energy and heat while burning only a small amount of additional fuel in HRSG at the main engine off-design operation.