Fuel Supply Process Research Articles

Influence of deforming of common rail diesel injectors parts on the fuel injection process

Experimental studies have revealed a significant impact of deformation of Сommon Rail injector parts on the fuel supply process. High pressures alter the structure of the fuel supply cy-cle. Theforward front of the fuel supply cycle begins with the stage of unloading the deformed parts of the injector. The rear front of the fuel supply cycle ends with the stage of deformation of the injector parts. The calculated and experimental determination of cyclic fuel supply gave similar results. The developed method of determining the duration of the injection cycle stages creates a basis for experimental verification of mathematical models. Keywords: injector, Common Rail, diesel, fuel system, electronic control, needle, fuel injection

Возможности применения водотопливной эмульсии с целью расширения рабочего диапазона дизеля и совершенствования процессов топливоподачи

В статье представлены результаты математического моделирования процессов топливоподачи судового дизеля при работе по винтовой характеристике при использовании дизельного топлива и водотопливной эмульсии с водосодержанием 30% в качестве аль­тернативного топлива. В результате исследования выявлены особенности процессов топливоподачи и влия­ние альтернативного топлива на рабочие характеристики впрыскивания серийной топлив­ной аппаратуры при работе на номинальном и частичных режимах. При оценке качества работы топливной аппаратуры учитывались: изменение характеристики подачи топлива; особенности распыливания топлива в начальной и конечной фа­зах впрыскивания; повышение стабильности последовательных циклов впрыскивания за счет увеличения активного хода плунжера; колебания остаточного давления в трубопро­воде высокого давления при последовательных циклах впрыскивания. При применении водотопливной эмульсии возможно существенное повышение каче­ства работы судового дизеля, расширение диапазона стабильных подач серийной топлив­ной аппаратуры как за счет возможности снижения скоростных режимов при малых подачах топлива, так и обеспечения форсированных подач топлива вследствие отсутствия повторных впрыскива­ний. The article presents the results of the mathematical modeling of marine diesel’s fuel supply processes during the screw characteristic while using diesel fuel and water-fuel emulsion with 30% water content as alternative fuel. As a result of the research, the features of the fuel supply processes and the effect of alternative fuel on the serial fuel equipment injection characteristics during operation in nominal and partial modes were identified. Considering the quality of fuel equipment operation the following features were taken into account, they are: changing fuel supply characteristics; features of fuel atomization in the initial and final phases of injection; increasing stability of the injection in sequential cycles by increasing plunger active stroke; residual pressure oscillations in the high pressure line during injection consecutive cycles. Using the water-fuel emulsion it is possible to significantly increase a quality of marine diesel engine operation, to extend the stable fuel supply range of the serial fuel equipment both from the possibility of speed modes reducing during fine fuel feed and providing forced fuel feed due to absence of repeating injections.

The concept of an automated educational system for the training of refueling complexes personnel

At present the aviation fuel supply industry is characterized by complex technological processes, in which possible incidents and accidents can lead to economic and environmental losses. These processes require highly qualified and specially trained engineering and technical personnel. The rapid development of digital technologies and their implementation in the technological processes for ensuring flights of aircraft aviation fuel, such as continuous monitoring of fuel cleanliness, the quantity and consumption records of aircraft aviation fuel using automated systems, as well as the use of new equipment, such as mass meters, which are highly accurate. All this requires a new approach to the training of the refueling complexes personnel. In addition, the development of refueling complexes is on the way to optimize the operations. So, for example, the responsibilities of the aircraft refueling operator are also assigned to the driver of the refueling tanker. Currently, the technical facilities of the warehouse and refueling complex equipment used for aircraft refueling are included as part of the airport infrastructure in order to ensure the flights regularity. Application of the new equipment using digital technologies is associated with improving the quality of refueling operations at all stages of aviation fuel supply. To ensure effective management of aviation fuel supply processes at all stages, the organizational structure should be based not only on modern equipment of all parts of the technological chain of fuel preparation, but also on a closed automated control system based on the introduction of modern, intelligent control and measuring devices. In these conditions, the issue of training personnel of fueling complexes becomes relevant. The solution to this issue is in the development of automated training systems, that allow to accelerate staff training and reduce the cost of training. Therefore, the article discusses the structural and functional model of an automated training system (ATS) that combines disparate solutions and forms a new system for solving problems of training, certification and information support for personnel of aviation fuel supply organizations (AFSO). The proposed training system allows training not only for one workplace, but taking into account individual characteristics, for example, to prepare both the driver of the vehicle and the refueling operator in one person. The article describes the scenarios of the use of ATS subsystems developed in the work, which determine the basic functional composition. In conclusion, based on the developed scenarios for the use of subsystems, the developed structural and functional model of the ATS is presented, which provides solutions to the problems of maintaining the operation of the AFSO and supporting decision-making.

Особенности моделирования гидродинамических процессов топливоподачи при работе судового дизеля на водотопливной эмульсии

The article presents the results of mathematical modeling of the fuel supply process of a marine diesel working on diesel fuel and water-fuel emulsion with a water content of 30% as an alternative fuel. There have been found the specific features of fuel supply and the influence of the alternative fuel on the injection characteristics of standard fuel supply equipment during operation in nominal and partial modes. In evaluating the quality of fuel equipment operation on a water-fuel emulsion there were taken into account the following facts: changing of the fuel supply characteristics; changing injection parameters; type of fuel spraying in the initial and final phases of injection and reduction of fuel proportion supplied during the needle landing period; greater stability of successive injection cycles by increasing the active stroke of the plunger by 25-30%; features of injection processes due to thermal explosion effect. The telegraph equation for the unsteady fuel motion in a high pressure pipeline is obtained. The operation parameters of a marine diesel engine 6CHSPN2A 18/22 (DRA-300) are considered in nominal mode according to the screw characteristic for diesel fuel and water-fuel emulsion: plunger stroke of the high-pressure fuel pump; maximum pressure of the steady state in the connecting pipe; average integral pressure of the steady state in the nozzle, which determines the quality of spraying, the speed of landing of the sprayer needle on the saddle; amount of fuel supplied during the needle landing period; cyclic fuel supply; duration of the main injection; stability criterion of fuel supply processes in successive cycles, etc. It has been inferred that water-fuel emulsions can take a separate place in the list of alternative fuels, which will contribute to improving the quality of traditional fuels, productive burnout of hydrocarbon, nitrogen-hydrogen mixture, spirit mixtures, etc. due to the rational introducing additives into fuel, increasing the reliability indicators of cylinder-piston parts, etc.

The use of reusable fuel injection with the aim of improving the economic and environmental performance of the diesel engine

The current trend in the development of motor-and-tractor diesel engines imposes tough requirements on fuel equipment and the fuel supply process. The implementation of it is difficult to combine with the requirements of reducing heat generation at the initial stage of combustion and the rate of pressure increment to reduce exhaust emissions and engine noise. A decrease in the duration of the injection process and an increase in the volumetric feed rate lead to a growth in the cycle dynamism factor and an increase in the operation noise. This scientific article discusses the use of multiple injection of fuel in a diesel engine to reduce the emission of nitrogen oxides, smoke and particulate matter by improving the heat transfer processes, the mixture formation and, as a result, heat generation. Low exhaust gases toxicity and smokiness values are achieved.

Совершенствование процесса топливоподачи в тепловозном дизеле

A topical problem of improving the fuel supply process in locomotive diesel engines in considered in this article. An ESUVT.01 type electronic control system developed by OOO PPP Dizelavtomatika (Saratov) for a D50 (6 ChN 31.8/33) locomotive diesel engine manufactured by Penzadizelmash is presented. It is shown that fuel efficiency and exhaust gas toxicity indicators can be significantly improved by optimizing the initial fuel supply phase, that is the injection advance angle. Experimental studies are conducted to assess the influence of this angle on the locomotive engine characteristics. Bench tests were carried out on a 1-PDG4D diesel generator consisting of the above-mentioned diesel engine and a traction generator MPT-84/39. As the result of the tests, dependencies of the diesel characteristics on the injection advance angle are obtained, and the need to optimize the injection advance angle according to the diesel operation mode is confirmed. Optimized values of the injection advance angle in the diesel characteristics modes are obtained. Fuel efficiency and exhaust gas toxicity indicators are determined at the optimized injection advance angle.

THE SIGNIFICANCE OF STOCK MANAGEMENT TO JET FUEL SUPPLY USING PARTIAL LEAST SQUARES

Operational and commercial efficiency at a jet fuel depot are vital indices for a jet fuel marketer toward ensuring maximum business productivity. In Nigeria, jet A-1 aviation fuel scarcity is a yearly challenge that periodically triggers jet fuel price increase, air fare price hike and flight cancellation. The causes of the scarcity have been ascribed to the challenges facing jet fuel supply process. In this study, the significance of each of the seven jet fuel depots of a fuel marketer to the overall business performance is analysed using structural equation modelling to evaluate the historical sales and stock data. Historical stock data contains hidden patterns and knowledge that can be acquired and applied in operational decision making processes. The effect of each depot on business performance is classified using the significance and path coefficient result obtained from the partial least squares model implemented on historical stock data. The analysis reveals the significance of adequate stock level via supply chain management, and this creates an opportunity for directing management policies and decisions at less significant depots based on the data-mined knowledge acquired. An overall model R2 value of 0.902 was achieved. This study therefore emphasises the relevance of quality data even in the aviation fuel industry.Keywords: Business performance analysis, supply chain management, partial least squares, fuel scarcity, jet A-1 aviation fuel, data pattern recognitionJEL Classifications: C53, N77, O25, Q3DOI: https://doi.org/10.32479/ijeep.8978

The study of the performance of a diesel nozzle on mixed fuels with insufficient low-temperature properties

Today, the properties of rapeseed oil, affecting the fuel supply processes in a tractor diesel, are density, kinematic and dynamic viscosity, as well as surface tension. The purpose of this research is to expand the limits of the fuel base of tractor diesel engines by using mixed fuels with insufficient low-temperature properties. In this regard, the determination of the optimal composition of mixed fuel for the operation of the fuel supply equipment of tractor diesels is a very urgent task. To solve this problem, theoretical studies were conducted to determine the effect of rapeseed oil additives on the properties of mixed fuels, as well as testing a diesel fuel injector. As a result of the studies, the dependences of the viscosity of the mixed fuel, the pressure of injection beginning, the tightness of the locking cone, and the hydro-density of the spray nozzle on the addition of rapeseed oil with an additive were determined. Based on theoretical calculations, the value of the viscosity of mixed fuel that meets the requirements of the manufacturer's specifications for fuel injectors is obtained. An analysis of the experimental dependences showed that with an increase in the proportion of rapeseed oil in mixed fuel from 0 to 100 %, there increased: the pressure at the beginning of injection from 20,88 to 21,08 MPa, the time until a drop of fuel comes off from the nozzle of the spray from 18 to 104 s, and pressure reduction time decreased from 5,2 to 11,3 s. Tests shown that for all mixed fuel compositions, the injection start pressure, tightness on the locking cone, spray water density and spray needle mobility meet the requirements of GOST 10579-2017, however, the spray quality corresponds to mixed fuel compositions with rapeseed oil up to 60 %. Thus, the use of the proposed fuel compositions will improve the low-temperature properties of mixed fuels with additives of rapeseed oil, and thus expand the fuel base of tractor diesels.

Modeling of the fuel system of a boiler turbine power plant with a homogenizer mixer to optimize the physical and chemical properties of fuel

Improving the technical, economic, and environmental performance of the power plant is the most important direction for improving the characteristics of the ship’s propulsive complex. This issue can be solved most effectively by improving the design, repair, and maintenance of the fuel supply system, which significantly affects the quality of the fuel equipment and determines the working process of the steam boiler. Performance indicators of fuel equipment are determined not only by the stability of its design and adjustment parameters and parameters of the fuel supply process, but also by the physical and chemical composition of the fuel.

Estimation model of the diesel engine fuel system with an electromechanical device to intensify fuel supply

The key directions of the development and improvement of the fuel supply system for internal combustion engines with ignition from compression of the fuel/air mixture were pointed out. The need for the comprehensive implementation of electromechanical principles of fuel injection control in accordance with the various conditions of diesel engines operation was proved. The relevance of further development and modernization of the hydromechanical fuel systems on the background of ever-increasing interest in their electro-controllable analogues was highlighted. The unused potential possibilities of hydromechanical fuel equipment to improve the conditions of the fuel supply process were listed. To intensify fuel injection, it was proposed to use the electromechanical device that is mounted in the fuel discharge pipeline and modifies the phase-amplitude characteristic of the wave process of propagation of a single supplying pulse between the high-pressure fuel pump and the hydromechanical nozzle. We highlighted the important aspects of the procedure for constructing the calculation model of the switchgear-type fuel system of direct action with a new device for fuel supply intensification. It was proposed to consider the fuel injection process at some stages, taking into consideration the characteristics of functioning of a particular hydraulic node of the fuel system, including the proposed technical means of intensification. The systems of differential and analytical equations that make it possible to perform mathematical modeling of the process of propagation and mutual influence of the pressure waves in the pressure-pumping tract were presented. The resulting systems make it possible to obtain characteristics of a change in hydraulic pressure in different fuel volumes, the kinematics of motion of shut-off elements in a high-pressure pump and nozzle, etc. In the course of a comparative study, carried out on the basis of the presented calculation model, the fuel injection process for the standard and improved fuel system for a turbo-diesel, a significant improvement of the injection quality by a large number of indicators was revealed. According to the results of calculations, the existence of high-rate character of increasing and decreasing of injection pressure at the initial and final phase of the process of fuel supplyi to the cylinders of a diesel engine is observed. It was noted that the rate of pressure change can reach 170 MPa/deg, maximum, and average injection pressure increases up to 75 MPa and 30...40 MPa, respectively. Calculation studies were carried out with the employment of the numerical method of integration – the Adams interpolation method, the choice of which is caused by the necessity of obtaining consistent solutions when solving the described systems of differential equations, which belong to the category of the rigid

Optimization of parameters for diesel shaft speed control system

This work presents a fuel supply electronic control system (model ESUVT.01) developed by Dizelavtomatika (Saratov) for the D50 (6 CHN 31.8/33) locomotive diesel engine manufactured by Penzadieselmash. In this system, the fuel supply process is controlled by a high-speed electro-hydraulic valve installed in the high-pressure line of the fuel system. A set of electrically controlled high pressure fuel pumps (mode 4ETN.03) with electro-hydraulic valves for the diesel was manufactured. This system can also control the engine speed. It was noted that the best quality indicators of the speed regulating process are provided by the PID control law. It was shown that for a diesel with high inertia, it is advisable to use the PI control law. Experimental studies were conducted to assess the influence of structure and parameters of this control system on the dynamic qualities of this diesel engine. The object of bench testing was a 1-PDG4D-type diesel-generator from the above-mentioned diesel engine and MPT-84/39 traction generator. The dependences of the duration of the transient process, the overspeed and the period of natural oscillations of the regulated parameter on the PI controller parameters were obtained. The necessity of optimizing the coefficients of proportional (P) and integral (I) components of the PI control law was confirmed. A method for optimizing the coefficients of proportional and integral components of the PI control law was proposed. The optimized coefficients for the transient acceleration process of the diesel engine according to the locomotive characteristic were obtained.

Advanced mathematical model of fuel supply operating process and results of calculations of fuel supply parameters for diesel engine running on composite rapeseed-mineral fuel

Results of theoretical studies are presented, their purpose was to assess the effect of heating of diesel composite fuel on cycle fuel supply and fuel pressure in the above-plunger space of a high-pressure fuel pump (HPFP). A refined mathematical model of the fuel supply process is described, which takes into account the concentration of rapeseed oil in composite rapeseed-mineral fuel and its physical properties, and theoretical justification of a method for determining the mean effective flow crosssection of nozzles and pressure fuel tubing is presented. The analysis results showed that with an increase in the concentration of rapeseed oil in composite diesel fuel and the revolution rate of HPFP camshaft at a temperature of 30 °C, a sharp decrease in the cycle fuel supply is observed which is smoother at heating. The same trend is observed with a change in the fuel pressure in the above-plunger space of HPFP.

INFLUENCE OF THE METERING METHOD ON THE CHARACTERISTICS OF A DIESEL DISTRIBUTOR FUEL PUMP

Objectives The aim of the study is to improve the performance of the metering system and thus enhance control over the cyclical supply of fuel to a diesel distributor pump. The results of a study of the effect of a new metering method on the characteristics of a distributor fuel pump are presented. Methods Following mathematical analysis, a mathematical model of the working process of the fuel supply system, based on a new metering approach employing the "decay of discontinuity" method, was compiled.The model comprises a system of differential equations for continuity and momentum alongside mass balance equations for describing the boundary conditions for various cavities of the fuel system, i.e. above the plunger, under the valve, above the valve cavities and in the nozzle. The differential equations take into account the two-phase nature of the gas-liquid medium in the injection cavities and metering system, as well as the design features of the pump. An expression for the stroke of the metering plunger in the new system is given. Results The theoretical and experimental characteristics of a fuel supply system employing the proposed metering system are considered. Diagrams showing maximum injection pressures, which depend on the stroke of the metering plunger at various strokes of the injection plunger and alteration of maximum injection pressure of the nozzle depending on the rotation speed of the cam shaft, are provided. The characteristics of the fuel supply system of the pump for various spring stiffness of the metering plunger are also provided in diagram form. The comparative parameters of the fuel supply process are presented for the conventional and new metering methods. The features of the use of diesel high-pressure distributor pumps, their design and operational features are described. The advantages of the metering system proposed by the author are presented in terms of its influence on the fuel injection process. A comparative evaluation of metering methods used in contemporary distributor pumps for diesel engines is given. Conclusion The results of the experiments confirmed the suitability of the new metering method for use in diesel engines.

Optimal co-scheduling of distributed generation resources and natural gas network considering uncertainties

Abstract It must be noticed that renewable energy resources operation with battery is the best method of electrical load cost provision. In this regard, integrated natural gas (NG) network with power system is utilized in this paper in order to increase system reliability and reduce pressure of power generators. In fact, NG is considered as clean and available fuel in order to support power system. It is possible to connect power system and gas network by Joint Unit (JU). JUs include Natural gas-fired distributed power generators (NGDG) and Power to Gas (PtG) units. In this paper, gas-fired turbine fuel supply process is prioritized. That is, desired gas is supplied by gas wells of gas network piping entry; PtG unit will supply NGDG gas as long as electricity cost is low. After optimal scheduling, By applying mixed integrated linear programming (MILP) for integrated system and two essential factors (power not supplied and gas not supplied), system operation under load and resources fluctuation studied. Finally, appropriate location and optimum capacity of new distributed energy resources for power system or compressor for gas network are selected. 24-Bus power system with renewable resources of Photovoltaic (PV) ،Wind Turbine (WT), battery energy storage, with 7- node natural gas network and two gas wells integration are selected as studied case for time range of 24 h in order to analyze process numerically.

Impact of diesel fuel and palm oil blend compositions on the performance of the fuel supply process in the diesel engine

The world experience of using palm oil as a fuel for diesel engines was considered. The influence of the mixture composition on the indices of the injection process at a constant value of the active stroke of the plunger and the mass cyclic feeding of the mixture, corresponding to the nominal cyclic feeding in the case of using only diesel fuel is analyzed. A comparative analysis of the change in the parameters of spraying of diesel fuel mixtures and palm oil fractions from 0% to 60% is performed depending on the specific parameters of the fuel supply equipment and the mixture (working stroke of plunger, cyclic feed and heat input). It is shown that changes in the fuel supply equipment parameters when using mixed fuels based on palm oil are not required, since the corresponding change in the volume cyclic feed and active stroke of the plunger with a change in the proportion of palm oil in the mixture to 60% does not exceed 3%. According to the requirements of the standard, these deviations are within acceptable limits.

Building a load characteristic of the fuel injection system of a ship’s medium-speed engine diesel in dynamic tests conditions

The object of research in the work is hydrodynamic processes in the high pressure fuel system of the ship’s medium-speed engine on variable modes. Variable regimes constitute a significant part of the operational time of a number of types of ships (tugs, fishing vessels, etc.), and for transport fleets they are characteristic for maneuvering. In the latter case, reliability and environmental safety for sanitary control zones are of particular importance. Studies of fuel supply processes in variable modes are important, since they largely determine all the operating characteristics of a diesel engine and are not well studiedThe article presents an experiment in which the task is obtaining the load characteristics and the study of transients in the fuel equipment of the ship’s medium-speed diesel engine under dynamic testing conditions. In the course of the research, a developed hardware and software complex is used to ensure the implementation of the experiment plan, fixation, processing and oscillography of the obtained data. An electromechanical system is developed by rack displacement of a high-pressure fuel pump with programmed computer control. The experiment program provides for changing the rack position in the whole range covering the operational load characteristic. The discrete displacement includes five fixed rack positions with a step transition between them. During testing, the high-pressure fuel pump completes 80 injection cycles over 44 s. The transition time between the individual fixed positions of the racks is 0.44 s. The stabilization period of hydrodynamic processes in the fuel supply system is close to 0.22 s. In the investigated range of rack positions mr=25–5 mm the main parameters of the fuel injection are as follows: рn.с=474–232 bar; рn.i=457–222 bar; рp=445–162 bar.The possibility of obtaining load characteristics by dynamic tests is shown, which significantly reduces the test time and increases the reliability of the data, eliminating the influence of the time trend parameters.

Моделирование процесса подачи топлив для дизелей наземной техники в условиях низких температур

Моделирование процесса подачи топлив для дизелей наземной техники в условиях низких температур

Dynamic characteristics of hydrocarbon fuel within the channel at supercritical and pyrolysis condition

Regenerative cooling with fuel as the coolant is used in the scramjet engine. In order to grasp the dynamic characteristics of engine fuel supply processes, this article studies the dynamic characteristics of hydrocarbon fuel within the channel. A one-dimensional dynamic model was proved, the thermal energy storage effect, fuel volume effect and chemical dynamic effect have been considered in the model, the ordinary differential equations were solved using a 4th order Runge-Kutta method. The precision of the model was validated by three groups of experimental data. The effects of input signal, working condition, tube size on the dynamic characteristics of pressure, flow rate, temperature have been simulated. It is found that cracking reaction increased the compressibility of the fuel pyrolysis mixture and lead to longer responding time of outlet flow. The responding time of outlet flow can reach 3s when tube is 5m long which will greatly influence the control performance of the engine thrust system. Meanwhile, when the inlet flow rate appears the step change, the inlet pressure leads to overshoot, the overshoot can reach as much as 100%, such highly transient impulse will result in detrimental effect on fuel pump.

Evaluation of the effect of fuel unevenness on diesel performance

In the vast majority of agricultural machinery, diesel is used as the engine. The amount of fuel supplied to the engine cylinders is the main factor determining its power, economic and environmental characteristics. It can be considered as a value composed of two parts: a controllable fuel supply system and uncontrolled, depending on the quality of the system. The deterioration in the performance of the engine is greater, the higher the proportion of uncontrolled part of the fuel supplied. The deviation of the amount of fuel supplied from a given fuel can occur in the following cases: uneven fuel delivery along the engine cylinders; instability of the fuel supply to the cylinder. If the uneven fuel flow through the cylinders is regulated by the requirements of GOST 10578-95 and is allowed depending on the operating mode from 6 to 35 %, then the instability of fuel supply from cycle to cycle is not regulated by standards and can be as high as 10-40 % according to other researchers. The combined influence of these parameters on the fuel supply process leads to a significant deviation in the cyclic fuel supply. The theoretical analysis of the main parameters of the engine showed that an increase in unevenness leads to a change in them, which worsens the indicator. This deterioration is the greater, the greater the degree of curvature of the line of change in the engine index from the change in fuel consumption. Based on the above results, the following conclusions are drawn: an increase in the unevenness and instability of fuel supply leads to a deterioration in the main engine performance; the degree of deterioration in the performance of the engine is greater the greater the unevenness and instability and the higher the nonlinearity of the curve of the change in the index from the fuel consumption; at present, the instability of fuel supply is not regulated, which does not allow controlling the quality of the process.

SCHEDULING PROBLEMS OF STATIONARY OBJECTS WITH THE PROCESSOR IN ONE-DIMENSIONAL ZONE

We consider the mathematical model in which an operating processor serves the set of the stationary objects positioned in a one-dimensional working zone. The processor performs two voyages between the uttermost points of the zone: the forward or direct one, where certain objects are served, and the return one, where remaining objects are served. Servicing of the object cannot start earlier than its ready date. The individual penalty function is assigned to every object, the function depending on the servicing completion time. Minimized criteria of schedule quality are assumed to be total service duration and total penalty. We formulate and study optimization problems with one and two criteria. Proposed algorithms are based on dynamic programming and Pareto principle, the implementations of these algorithms are demonstrated on numerical examples. We show that the algorithm for the problem of processing time minimization is polynomial, and that the problem of total penalty minimization is NP-hard. Correspondingly, the bicriteria problem with the mentioned evaluation criteria is fundamentally intractable, computational complexity of the schedule structure algorithm is exponential. The model describes the fuel supply processes to the diesel-electrical dredgers which extract non-metallic building materials (sand, gravel) in large-scale areas of inland waterways. Similar models and optimization problems are important, for example, in applications like the control of satellite group refueling and regular civil aircraft refueling. The article is published in the author’s wording.