Locomotive Traction Research Articles

Оценка эффективности использования тепловозов 3ТЭ10М на участке Мароканд – Каттакурган Узбекских железных дорог

The results of research on the justification of the parameters of freight with three-section mainline (crew) diesel freight locomotives 3 ТЭ 10 М on the railway section between Marokand – Kattakurgan with the route Samarkand – Navoi – Bukhara on Uzbek railways are presented, that were obtained by the famous locomotive traction theory. The values of parameters of main indicators of freight with studied diesel freight locomotives 3ТЭ10М were specified as a result of the performing the series of grade computations for different conditions of the organization of freight traffic on the section Marokand – Kattakurgan. Moreover, these values are presented in tabular data and graphic dependencies. Average and arithmetic mean values of main indicators are determined with the regard to freight trains without stopping and with stopping on interstation. The regression equations are obtained that intended for the calculation of averaged parameters’ values of the main indicators for fuel and energy efficiency to utilize the studied diesel freight locomotives 3 ТЭ 10 М in real conditions of the organization of rail freight transportation for the accepted range of mass’ variation of freight trains. The results of research are recommended for the practical utilization by locomotive drivers-instructors and specialists of the linear locomotive enterprises on the Uzbek railway network whose professional and production activities relate to issues of the diesel fuel saving for the haulage of trains.

Variable width tillage tool

To ensure the operating efficiency of plowing unit it is required to comply with the specified speed regime of motion and optimal loading of tractor engine. Difference of tractive resistance of soil in different fields creates a situation where it is difficult to select the optimal loading of tractor engine providing constant speed. For example, for the fields with a specific resistance equal to 20 000 and 30 000 newton per square meter, tools with grasp width equal to 2.4 and 1.9 meters respectively are required. The aim of the paper is to find a design scheme of variable width tillage tool, which provides the necessary reliability and reduces the complexity of grasp width regulation. The main research method in achieving this goal is the rational use of condition of external force loading of working organs of tillage tool. The condition of external loading of working organs is investigated. The principal vector and principal moment are accepted as external load equivalents. The conditional center of external soil pressure on working organ is determined by finding the points of intersection of the axis of thrust-and-torque combination with the working surface of plow body. As a result of study, the design scheme of tillage tool that provides the necessary reliability and reduces the complexity of grasp width regulation is proposed. The value of external cutting forces in the obtained scheme is used as a sensor of specific resistance of soil in a specified field and provides the adjustment of grasp width of tool under optimal loading of tractor engine.

Application of storage catalytic converters of nitrogen oxides for reducing exhaust toxicity of tractor diesel engines

Reduction of harmful effects of agricultural machinery on the ecosphere is an important task; its solution requires extensive use of emission reducing devices. Compliance with up-to-date legal requirements causes the cost increase of systems of diesel exhaust gases aftertreatment. This applies especially the systems that require an additional reagent feeding into exhaust system. The cost factor determines the study aim that is the creation of prototype of alternative aftertreatment system for selected engine type with the possibility of rapid adaptation to other types of the same power class. The article considers the operating principles of a storage-type system of catalytic reduction of nitrogen oxides, the design features of the system for tractor engine. An important advantage of this system is the fact that there is no need for additional reagent. The experimental studies of converter prototype as part of series-production engine were conducted on the engine test bench. In addition, the tests of samples of catalyst bricks with different types of catalytic coating were carried out. As a result of testing and selection of optimal catalytic coating, the new fuel supply system with increased performance is obtained and the converter design recommended for agricultural machinery is modified. The storage catalytic converter system allows to reduce the nitrogen oxides emissions by 40-50 %. With such efficiency of the system, its cost is noticeably lower than the cost of the system of selective catalytic reduction. The proposed design allows to adapt the storage system to engines of any power class without change in systems and control algorithms. The optimal field of application of storage systems is determined.

The effect of water-diesel emulsion usage on a tractor engine performance and emission

This manuscript evaluates the effect of emulsified diesel fuel on the engine performance and emission for a water-cooled, four stroke, four cylinders and direct injection diesel engine. The water content of emulsified diesel fuels is in the range of 0–10% by volume. During experiments, the engine speed was varied from 1600 rpm to 1900 rpm. It is noted that that the emulsion fuel containing 2% water content had greater engine power and torque values and lower exhaust emissions. The overall engine noise emission was found to increase with engine speed. It also could be seen that the emulsified diesel fuel combustion did not increase the engine noise comparing to neat diesel fuel. From this study, it could be concluded that using this type of emulsion could improve the engine performance with the decrease in the exhasut emission. Therefore, it could be a good alternative for using in diesel engines.

Loading conditions of pistons of internal combustion engines and causes of crack formation on combustion chamber edge

In order to develop the methods for assessment of durability of pistons of tractor diesel engines, it is necessary to conduct the research of causes of failures in their operation, in particular crack formation on the edge of combustion chamber. Tractor engines operate in transient regimes due to periodic changes of control organ position and resisting moment when tractor performs agricultural, logging and other works. In transient regimes, the stress-strain state of piston varies in time, which leads to the formation of fatigue cracks on the edge of combustion chamber. The paper reviews the studies on regularities of change in the rate of propagation of fatigue cracks on the edge of combustion chamber of tractor diesel engine. The peak values of heat flows passing through the heat-absorbing surface of piston head in transient regimes exceed by 2.5 times the same values in steady-state regimes. According to the researches, for the 4ChN 11/12.5 tractor diesel engine stress intensity on the edge of combustion chamber caused by temperature gradients equals to 92-98 MPa, and exceeds more than by 2 times the stresses caused by gas pressure forces in cylinder (38-42 MPa). With the increase of engine forcing, the edge of combustion chamber becomes a local concentrator of thermal stresses, that leads to elastic-plastic deformations of cyclical pattern and microdefects. Stresses appearing on the edge of combustion chamber under rapid change of loading modes typically exceed the values of yield stress of piston material. This leads to the appearance of plastic deformations on the edge of combustion chamber. The analysis of causes of crack formation on the edge of combustion chamber of piston of a tractor diesel engine shows that when assessing the durability of piston, the whole range of indicators and parameters of the engine should be taken into account.

English

Renewable energy benefits and disadvantages have been subject of major discussions and studies. Thus, this study aimed at assessing the smoke opacity from a farming tractor running two types of diesel, B S1800 (B0) and B S10 (B0), and ethyl biodiesel from babassu oil at two rates (B50 and B100), at six day periods (2, 6, 10 am, 2, 6 and 10 pm). The study was conducted at the Department of Agricultural Engineering of the Faculty of Agricultural and Veterinary Sciences, UNESP, in Jaboticabal - SP, Brazil. The results showed a reduced smoke opacity during daytimes of lower ambient temperature and higher air relative humidity. In addition, smoke opacity was reduced as higher rates of babassu biodiesel were added to B S1800 diesel and B S10; thus, consisting of an efficient procedure of reducing smoke opacity in farming tractor engines. Key words: Biofuel, emissions, pollutants, renewable energy, diesel engine cycle, Orbinya martiana.

Analysis of the effects of operating point of tractor engine on fatigue life of PTO gear using simulation

Agricultural tractors are designed using the empirical method due to the difficulty of measuring precise load cycles under various working conditions and soil types. Especially, directly drives various tractor implements, the power take off (PTO) gear. Therefore, alternative design methods using gear design software are needed for the optimal design of tractors. The objective of this study is to simulate fatigue life of the PTO gear according to the operating point of the tractor engine. The PTO gear was made with SCr415 alloy steel with carburizing and quenching treatments. The fatigue life of the PTO gear was simulated by using bending and contact stress according to the torque of the load levels. The PTO gear simulation was conducted by the KISSsoft commercial software for gear analysis. Bending and contact stress were calculated by the ISO 6336:2006 Method A and B. The simulation of fatigue life was calculated by the Miner's cumulative damage law. The total fatigue life of tractors can be estimated to 3,420 hours; thus, 3,420 hours of fatigue life were used in the simulation of the PTO gear of tractors. The main simulation results showed that the maximum fatigue life of the PTO gear was infinite fatigue life at maximum engine power. Minimum fatigue life of the PTO gear was 19.61 hours at 70% of the maximum engine power. Fatigue life of the PTO gear changed according to load of tractor. Therefore, tractor work data is needed for optimal design of the PTO gear.

NOISE REDUCTION IN FUEL INJECTION PUMPS OF TRACTOR ENGINES USING ‘IS AND IS-NOT APPROACH’

An industry makes fuel injection pumps for tractor engines. Recently it was observed that the fuel injection pumps were making too much noise in the engines. The problem-solving techniques of industrial engineering were used to solve this problem. One such simple but powerful problem-solving technique is the ‘is and is-not’ approach. This technique was used to identify the root cause of the increased noise of the fuel injection pumps. Once the cause was identified, the problem was rectified. Thus the industry was able to reduce the noise of the fuel injection pumps.

Change of the structure and properties of the tribo-preparations to increase the efficiency of tractor engine in-place repair

The structural changes of the ultrafine compounds and removal of impurities and resins from the operating oils are necessary to increase the efficiency of the in-place repair of tractor engines under the action of the repair-recovery compounds, tribo-preparations. It was revealed as a result of the electron microscopy that the tribo-compounds consisting of molybdenum disulfide, cuprum, and phosphorus modifies its chemical composition, which decreases after being exposed to ammonium hydroxide. To neutralize the action of the oxidation products in the operating engine oil, carbonic acid diamide capable of enlarging the resins, asphaltenes, carbenes, and carboide dissolved in the oil is added into the tribo-preparation composition. Adding the structure lubricating composition to operating engine oil enlarges the impurities' particle size from 0.1–0.5 to 10–20 μm, so that they can be easily removed by the centrifuges included into the lubrication system of the combustion engine. According to the results of evaluation of the antiwear properties of the lubricating compositions consisting of the operating oil with the admixture of the unstructured and structured tribo-preparation, the reduction of the wear spot by 50% in favor of the latter is specified. The comparative bench tests of the repair and recovery compounds before and after structuring showed a high recovery effect of the second (structured) composition.

Evaluation of a tractor diesel engine noise fuelled by water-diesel emulsion

The objective of this study was to investigate the noise emitted from a tractor diesel engine, Perkins A63544, using neat diesel fuel and water-diesel emulsions (2, 5, 8 and 10% water by volume). The engine noise was measured at tractor driver’s ear position at four levels of engine speeds ranging from 1600 to 1900 rpm with steps of 100 rpm. No change in the engine components and fuel injection systems was made. The tractor engine sound at driver’s ear position was measured by a HT 157 sound level meter in a test site, which was prepared and managed according to ISO 5131 standard. The time domain engine sound signals were recorded in a computer hard disk. The digital sound in time domain was converted to frequency domain using FFT algorithm. The results obtained from 1/3rd octave frequency band showed that the greatest sound pressure level was observed at firing frequency. The loudest engine sound was found for neat diesel and E 2 emulsion, while the combustion of E 8 emulsion had the lowest noise emission. The statistical analysis showed significant effects (P 0.01). The results also showed that the overall engine noise was very high and could be dangerous for the driver health. The driver’s exposure time should be less than one hour/day and there is needed to implement the noise control program for the tractor and driver.

An Approach for Power Generation with Reduced Fuel Consumption using PTO Driven Generator

Using the gear up throttle down concept, suitable power take off (PTO) speed required to run a PTO powered generator was decided. For this PTO test was carried out using an eddy current dynamometer. The tractor engine was loaded to different torque values at different engine speeds for obtaining constant PTO power corresponding to the full load of the generator. Fuel consumption, smoke level, exhaust gas temperature and coolant temperature were measured during PTO test. Engine speed fluctuation and engine overloading were also observed to judge whether the engine was running smoothly, or it was overloaded. The specific fuel consumption was reduced from 268.9 g/kW h at 1579 rpm to 242.9 g/kW h at 1000 rpm. Considering the engine speed fluctuation, overloading of the engine, rapid rise of smoke level, exhaust gas temperature and coolant temperature, an engine speed of 1215 rpm was recommended instead of 1579 rpm (corresponding to standard PTO speed of 540 rpm). A suitable power transmission system comprising belt and pulley drive was designed to run the generator at rated speed of 1500 rpm. When the generator was operated at reduced PTO speed of 415 rpm (corresponding to engine speed of 1215 rpm) in comparison to standard PTO speed of 540 rpm, fuel saving of 0.35 l/h to 0.55 l/h and 0.43 l/h to 0.48 l/h was achieved at different alternating current (AC) and direct current (DC) loads on the generator, respectively. Following this approach, a considerable amount of fuel energy could be saved while generating electric power using tractor. Efficient use of fuel will reduce the overall production cost of agricultural products as well as help in protecting our environment.

Dynamic response of a locomotive with AC electric drives to changes in friction conditions

Locomotive traction control behaviour and its dynamic impacts on rails and vehicles have not been comprehensively investigated in respect to transient conditions. Such transient traction behaviour could be more significant than steady state behaviour in determining dynamic traction performance and track degradation (i.e. squat/corrugation formation, etc.). In order to study this effect, detailed numerical simulations are performed to investigate a locomotive’s dynamic response to a change in contact conditions. In particular, creep response, vibration of the locomotive, and dynamic normal and traction forces are determined using a developed full-scale dynamics model of a locomotive. The model includes a detailed representation of the AC motor dynamics, which has not been considered in previous works. The results show that the detailed model is capable of simulating the dynamic fluctuations in creep and traction forces that are not considered in simpler models. Such transient responses may cause damage to the track and vehicle components.

The Influence of Common-rail Adjustment on the Parameters of a Diesel Tractor Engine

The article deals with the issue of high-pressure indication of a diesel tractor engine Z 1727, which was fitted with a modern electronically controlled common-rail injection system. The aim of the study is to evaluate the influence of the adjustment of the fuel system – start of injection (SOI) timings and the rail pressure (PRAIL) – on the pressure development in the cylinder (PCYL), the heat release (HR) and the combustion noise level (CNLA). Furthermore, the article examines the influence of pilot and post fuel injections on the CNLA. The experiments were conducted at constant speed (1480 rpm) with four PRAILs and different SOI timings. As the results of measurements have shown, higher rail pressure causes higher pressure and a release of a larger amount of heat in the cylinder. These two parameters are the basic prerequisite for higher engine efficiency – higher power output of the engine at lower fuel consumption and decreased production of harmful emissions. Other advantages of the common-rail fuel system include the potential of dividing the main injection dose into the pilot injection and main injection, as well as the potential post injection. The measurements have further demonstrated that including a pilot injection phase significantly contributes to a decrease in combustion noise level as well as a more even, quieter operation of the engine.

Performance of an agricultural engine using blends of diesel and ethanol

ABSTRACT: This research evaluated the performance of a diesel engine in an agricultural tractor, using Diesel S500 (B5) and mixture with 3% (ED3), 6% (ED6), 9% (ED9), 12% (ED12) and 15% (ED15) of hydrous ethanol. Variables evaluated were the power, torque, specific fuel consumption, torque reserve, speed reserve and elasticity index of engine. Results indicated that using B5 and ED3 the values of torque and engine power not differ, in addition, with the ED3 the fuel consumption was lower than 5.92%. Using ED12, power has reduced in 2.97%, compared with B5, while their fuel consumption had no difference. With ED15, the power was lower 6.30% and the fuel consumption increase 3.77%, both compared with B5. Torque reserve value was increased with increasing the ethanol content in B5, reducing the speed reserve and elasticity index of engine. Ethanol in Diesel S500 (B5) can be used as an alternative fuel in agricultural tractor engines without presenting high changes in the performance, since the ethanol content is at low percentages, up to 12%.

Modelling total weighted vibration of a trailer seat pulled by a two-wheel tractor consumed diesel–biodiesel fuel blends using ANFIS methodology

The application of adaptive neural-fuzzy inference system (ANFIS) to predict the total weighted vibration acceleration of a trailer seat pulled by a two-wheel tractor is set out in the present paper. The vibration acceleration signals were obtained in a field experiment using a 9.5 kW two-wheel tractor. Three accelerometers were installed at three orthogonal directions according to ISO 2631-1 standard on the trailer seat for measuring and recording the vibration acceleration signals. The two-wheel tractor consumed diesel–biodiesel fuel blends, and the engine speed and gear ratio were varied to cover normal range of operation in transportation conditions on asphalt rural road. The digital recorded vibration acceleration signals in time domain were converted to the frequency domain using Fast Fourier Transform algorithm, and the one-third octave frequency bands were obtained. The one-third octave frequencies were weighted according to the ISO standard. Altogether, 100 patterns were generated for training and evaluation of ANFIS. The input parameters of ANFIS were the tractor engine speed, transmission gear ratio of the tractor and fuel blend type, and the output parameter was the trailer seat total weighted vibration acceleration. The ANFIS structure was designed based on the grid partition, fuzzy c-means clustering and subtractive clustering. The results revealed that the ANFIS with subtractive clustering method was the best for accurate prediction of the total weighted vibration acceleration of the trailer seat. The number of rules, root-mean-square error (RMSE) of train, RMSE of test, correlation coefficient (R) of train and R of test values for the optimized structure were 5, 0.1479, 0.2141, 0.9175 and 0.8804, respectively.

Methodology to analyse farm tractor idling time

Actual in-service damage to tractor engines could be different from that predicted according to other estimates due to the difficulties in evaluating all the information necessary to completely define the mission profile. Among the different parameters which could be measured or estimated, the idling duration is one of the most influential factors in the calculation of in-service damage. In this paper, a methodology to estimate the idling time from signals recorded through a data logger interfaced to the vehicle-bus is proposed. Through statistical methods, the idling duration distribution was identified for a fleet of 61 New Holland T9 farm tractors used in Europe and in North America. Starting from these distributions the percentiles have been estimated. The recorded values of idling duration range from 5% up to 50% and the average value is about 20% of the tractor life. Furthermore, 97.5% of the analysed tractors run under idling condition for greater than 10% of the whole life of the machine. All tractors have made at least a stop shorter than 1920 s, while not all have made a stop longer than 1920 s. From the analysis, tractors located in areas with extreme temperatures have run under idling conditions for a longer time to keep the cab comfortable or to maintain the engine on temperature. This data confirms the importance to considering the geographical distribution of the machines and the necessity of performing a wide acquisition campaign to define the tractor mission profile.

Modelling of track wear damage due to changes in friction conditions: A comparison between AC and DC electric drive locomotives

The locomotive traction motor electric dynamics and its impact on the rail and vehicle have not been investigated deeply in transient wheel–rail contact conditions. Such transient traction behaviour could be more significant to dynamic traction performance and track degradation (i.e. corrugation formation, fatigue, wear, etc.) than steady state behaviour. In order to study this, detailed numerical simulations are performed to investigate the locomotive multi-body dynamic response to a change in contact conditions with an AC and DC electrical traction motor respectively. In particular, creep response, locomotive vibration, and dynamic normal and tractional forces are determined using a developed full scale locomotive dynamics model. The model includes the detailed AC and DC motor dynamics. Further investigation has been undertaken to understand the wear caused during and after the change of friction conditions from dry to wet and wet to dry. The result shows the GT46Ace locomotive AC drive can achieve higher traction efficiency compared to the equivalent DC drive running under notch 8, especially in the wet condition. It is also demonstrated that the AC drive produces slightly lower wear on average than the DC drive after the transient. However, the transient dynamic oscillation of wear caused by the AC drive is significantly higher than the DC drive.

Implementation of a wheel–rail temperature model for locomotive traction studies

ABSTRACTCalculation of the temperature in the contact zone at the wheel–rail interface is a very complex and important issue for multidisciplinary railway studies. The knowledge of temperature in the contact interface between two bodies, and with the possible presence of a third body interfacial layer, allows making informed judgments on processes in areas such as lubricant choice, wear estimation, life cycle prediction, etc. This paper focuses on development of a temperature modelling methodology in Gensys, and also presents its implementation for the study of temperatures at different contact points (top of rail, gauge corner, and gauge face contacts). In operational practice, all these mentioned contacts have different coefficients of friction which should be characterized as velocity and slip-dependent variables. To demonstrate the workability of the developed methodology, numerical experiments for a heavy haul locomotive equipped with a simplified bogie traction control system have been performed on curved track, where a locomotive has been operated under maximum traction forces and with longitudinal and lateral coupler forces attached in order to take into account train dynamics. Both new and worn rail profiles have been used. Limitations of the proposed methodology as well as proposed future work and further improvements are discussed.

A neural network driving curve generation method for the heavy-haul train

The heavy-haul train has a series of characteristics, such as the locomotive traction properties, the longer length of train, and the nonlinear train pipe pressure during train braking. When the train is running on a continuous long and steep downgrade railway line, the safety of the train is ensured by cycle braking, which puts high demands on the driving skills of the driver. In this article, a driving curve generation method for the heavy-haul train based on a neural network is proposed. First, in order to describe the nonlinear characteristics of train braking, the neural network model is constructed and trained by practical driving data. In the neural network model, various nonlinear neurons are interconnected to work for information processing and transmission. The target value of train braking pressure reduction and release time is achieved by modeling the braking process. The equation of train motion is computed to obtain the driving curve. Finally, in four typical operation scenarios, comparing the curve data generated by the method with corresponding practical data of the Shuohuang heavy-haul railway line, the results show that the method is effective.

A METHOD FOR TRAIN WEIGHT ESTIMATION

[For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT There are difficulties and deficiencies in procedures of weighing of railway cars and trains, as well as there is a persisting need to know cargo loads on the rail track. The article offers a simple way to estimate weight of a train as it moves along a control track section. It is based on measurement of intensity of magnetic field generated by locomotive DC traction motors. The role of weighing devices is performed by ferroprobes having as recording devices milliammeters with a calibrated scale for measuring train weight. The results achieved by the authors confirm method’s effectiveness. Keywords: train weight, locomotive, DC traction motors, constant magnetic field, magnetic field intensity, ferroprobes, train weighing method.