Engine Power Requirements Research Articles

Analysis of the Effect of Tillage Depth on the Working Performance of Tractor-Moldboard Plow System under Various Field Environments.

The purpose of this study was to analyze the tillage depth effect on the tractor-moldboard plow systems in various soil environments and tillage depths using a field load measurement system. A field load measurement system can measure the engine load, draft force, travel speed, wheel axle load, and tillage depth in real-time. In addition, measurement tests of soil properties in the soil layer were preceded to analyze the effect of field environments. The presented results show that moldboard plow at the same tillage depth had a wide range of influences on the tractor’s working load and performance under various environments. As the draft force due to soil–tool interaction occurred in the range of 5.6–17.7 kN depending on the field environment, the overall mean engine torque and rear axle torque were up to 2.14 times and 1.67 times higher in hard and clayey soil, respectively, than in soft soil environments. In addition, the results showed tractive efficiency of 0.56–0.73 and were analyzed to have a lugging ability of 67.8% with a 44% maximum torque rise. The engine power requirement in hardpan was similar within 3.6–9.6%, but the power demand of the rear axle differed by up to 18.4%.

Research on Main Engine Power of Transport Ship with Different Bows in Ice Area According to EEDI Regulation

The Energy Efficiency Design Index (EEDI) has been applied to ship carbon emission standards since 2013, ice ships subject to the Finnish Swedish Ice Class Rules (FSICR) also need to meet the requirements of EEDI. In this study, the engine power requirements by EEDI at different stages for the considered ice class ships with different ice classes (1C, 1B, 1A, 1A Super) are compared with engine power requirements obtained from the resistance calculated by FSICR or Lindqvist method. Three different bow shapes for the considered ice class ships and different pack ice coverage are studied. The results from FSICR or Lindqvist formula show that 1A Super ice classes for all considered bow shapes cannot meet the requirement by EEDI at Phase 2 and 3; For 1B and 1A class, some bow shapes can meet the EEDI requirement for all stages, but some cannot; For 1C class, all bow shapes can meet the EEDI requirements for all stages. The ship main engine power requirements under different pack ice concentration are studied and compared to EEDI requirements.

Justification of the required hold-down dependence on the length and angle of high-angle pressure belt conveyor

High-capacity and high-angle pressure belt conveyors which come into use in open pit mines in Russia and in the post-Soviet space, as well as acknowledgment of their economic efficiency made large mineral mining companies interested in installation of such equipment. The related research and empirical data grow in number. However, conveyors currently operated in Russia and in the CIS countries are manufactured abroad. Both domestic and foreign technical literature lacks a commonly accepted design policy of the conveyors. Furthermore, most foreign-manufacture high-angle pressure belt conveyors have small angles and lengths. In the meanwhile, open pit mines in Russia need long high-capacity and high-angle conveyors. Many aspects of justification of high-angel conveyor parameters are sufficiently elucidated in technical literature. The estimate of the hold-down and its dependence on the angle and length of a conveyor is yet deficiently studied. The value of the hold-down has a direct influence on the conveyor characteristics, including resistance to motion and engine power requirements. Accordingly, this article analyzes the influence exerted by the angle and length of a conveyor on the hold-down. The stress state of the load on the belt of the high-angle conveyor is analyzed, and the required holddown is evaluated with respect to the conveyor capacity, angle and length. It is known that hold-down governs loading of the load-carrying branch, which affects its service life. The analysis shows that 30 % of down-time of high-angle conveyors in the world is caused by failures of the load-carrying branch. The relations are proposed for determining the required linear hold-down versus the length of a conveyor to ensure sliding of cargo layers relative to each other and relative to the belt along the longitudinal axis of the conveyor. The recommendations on hold-down distribution along the conveyor to slacken the hold-down influence on the resistance to motion and on the engine power are proposed.

Proposed Inland Oil Tanker Design in Bangladesh Focusing CO2 Emission Reduction Based on Revised EEDI Parameters

Though inland ships account for a small portion of the total global CO2 emissions from shipping, from the individual country’s economic and environmental perspective, this is very important. To reduce CO2 emissions from sea-going ships by increasing energy efficiency, the International Maritime Organization (IMO) adopted a generalized Energy Efficiency Design Index (EEDI) in 2011. However, due to the variation in environmental, geographic and economic conditions, a generalized EEDI cannot be established in a similar fashion to that established by IMO. Shallow and restricted water effects, different fuel qualities (to reduce operational cost), increase in engine power requirements, reduction in carrying capacity, cargo availability, etc. make the EEDI by IMO inadequate for inland waterways. Therefore, an EEDI formulation based on revised parameters has been proposed for the inland ships in Bangladesh. This paper focuses on the possibility of CO2 emissions reduction from inland oil tankers in Bangladesh by implementing the revised EEDI formulation (henceforth denoted as EEDIINLAND). A sensitivity analysis was performed for the different ship design parameters of those oil tankers. Based on the analysis, suggestions were made on how to design inland oil tankers in Bangladesh using the revised EEDI formulation for reducing CO2 from the current level without any major cost involvement. Keeping the same speed and capacity, the vessels were redesigned based on those suggestions. The Computational Fluid Dynamics (CFD) analysis of those redesigned vessels using ‘Shipflow’ showed a reduction in CO2 emissions through increasing EEDIINLAND by 7.54–13.65%.

Computational Investigation of a Boundary-Layer-Ingestion Propulsion System

The present paper examines the potential propulsive and aerodynamic benefits of integrating a boundary-layer ingestion propulsion system into the Common Research Model geometry and the NASA tetrahedral unstructured software system. The numerical propulsion system simulation environment is used to generate engine conditions for computational fluid dynamics analyses. Improvements to the boundary-layer ingestion geometry are made using the constrained direct iterative surface curvature design method. The potential benefits of the boundary-layer ingestion system relating to cruise propulsive power are quantified using a power balance method, and a comparison to the baseline case is made. Iterations of the boundary-layer ingestion geometric design are shown, and improvements between subsequent boundary-layer ingestion designs are presented. Simulations are conducted for a cruise flight condition of Mach 0.85 at an altitude of 38,500 ft, with a Reynolds number of 40 million based on the mean aerodynamic chord and an angle of attack of 2 deg for all geometries. The results indicate an 8% reduction in engine power requirements at cruise for the boundary-layer ingestion configuration as compared to the baseline geometry. Small geometric alterations of the aft portion of the fuselage using constrained direct iterative surface curvature are shown to marginally increase the benefit from boundary-layer ingestion further, resulting in an 8.7% reduction in power requirements for cruise, as well as a drag reduction of approximately 12 counts over the baseline geometry.

Thermal Design of Linear Induction and Synchronous Motors for Electromagnetic Launch of Civil Aircraft

The engine size of modern passenger transport aircraft is principally determined by take-off conditions, since initial acceleration requires maximum engine power. An electromagnetic launch (EML) system could provide some or all of the energy required at takeoff so that the aircraft engine power requirement and fuel consumption may be significantly reduced. So far, EML for aircraft has been adopted only for military applications to replace steam catapults on the deck of aircraft carriers. This paper will describe the potential application of EML to propel civil aircraft on the runways of modern airports. A comparison of synchronous and asynchronous electrical motor systems designed to launch an A320-200 sized aircraft is presented. The paper also describes a solution of the transient heat transfer problem applied to the conductive components of EML systems.

Energy Management for an 8000 hp Hybrid Hydraulic Mining Shovel

There has been an increasing interest in concept of hybrid architecture which is penetrating the heavy industry machines, in recent years, including for hydraulic mining shovels (HMSs). Achieving increased machine efficiency, productivity, and performance, reduced emissions, and prolonged lifetime are the main goals in developing hybrid shovel structures. This paper presents the energy management concept for an electric HMS, which uses high power density energy storage systems to supplement the diesel-powered generators. A 2.25-MW ultracapacitor system is applied to improve the sluggish dynamic response of the diesel engines during sudden load changes and to reduce the engine power requirements by maintaining an optimal engine speed. In addition to the engine dynamic improvement, the ultracapacitor system supports the engine during peak power demand allowing for a smaller engine size, which results in higher fuel savings and less exhaust emissions. Detailed control schemes for the converters and system are described. Results of simulations, off-board testing, and on-board testing for an implemented 8000 hp mining shovel are provided and discussed. The machine operates smoothly at varying load conditions. The initial assessments indicate a 30% increase in machine productivity and 26% increase in fuel efficiency compared with a 120-ton conventional hydraulic machine.

Importance of automatic variable single hitch point for 2WD tractors – A theoretical analysis

Software is developed in Visual Basic 6 environment for predicting the haulage performance of 2WD tractor. Three types of inputs namely tractor, trailer and operating parameters are required to run the software. Various empirical and theoretical equations were used for predicting the haulage performance parameters such as draft, slip, actual speed, transport productivity, transport efficiency, fuel economy index, front and rear wheel utilization factor etc. In addition to this, the software also gives a warning signal when either stability of tractor or engine power fails. It was used to evaluate the haulage performance by varying the hitch height (HH) at various operating conditions. It was observed that there is a significant increase in the maximum payload 78, 300 and 3300% while HH was lowered from 0.7 to 0.1 m at 0, 5 and 10° slope, respectively. However, the dynamic load on rear axle increased from 1470 to 1730 and 1500 to 1820 kg when HH increased from 0.1 to 0.7 m at 800 and 1000 kg payload, respectively. Further, it was observed that fuel economy index was reduced by 6.3% and engine power requirement by 4.23% at 800 kg payload when HH was raised from 0.1 to 0.7 m. It was observed that stability of tractor increases by lowering the HH, however, traction increases by raising the same. Hence, it was concluded that variable HH can meet the requirements of stability as well as traction during transport as per necessity.

Dynamic Performance Improvement and Peak Power Limiting Using Ultracapacitor Storage System for Hydraulic Mining Shovels

This paper presents a concept to improve the dynamic response, efficiency, productivity, and fuel consumption of hydraulic mining shovels (HMSs) using a high power energy storage system to supplement the existing diesel-powered generators. A 2.25-MW ultracapacitor system is applied to improve the sluggish dynamic response of the diesel engine during sudden load changes and to limit the engine power requirements by maintaining an optimal engine speed. When the load rate of change increases above a specified rate limit, the ultracapacitor system supplements power to support loads in order to limit the power ramp rate for the generator. In addition to the engine dynamic improvement, the ultracapacitor system supports the engine during peak power demand, allowing for a smaller engine size for the machine, which results in higher fuel savings and less exhaust emissions. An interleaved bidirectional dc/dc converter is designed to interface between the ultracapacitor bank and main dc bus. Sophisticated multilayer control strategies are designed, implemented, and applied to the system to perform complete machine power management while keeping the dc bus voltage stable. Modeling and experimental results for an 8000-hp HMS with the novel electrification architecture have also been presented.

Propulsive power contribution of a kite and a Flettner rotor on selected shipping routes

Wind is a renewable energy source that is freely available on the world’s oceans. As shipping faces the challenge of reducing its dependence on fossil fuels and cutting its carbon emissions this paper seeks to explore the potential for harnessing wind power for shipping. Numerical models of two wind power technologies, a Flettner rotor and a towing kite, are linked with wind data along a set of five trade routes. Wind-generated thrust and propulsive power are computed as a function of local wind and ship velocity. The average wind power contribution on a given route ranges between 193kW and 373kW for a single Flettner rotor and between 127kW and 461kW for the towing kite. The variability of the power output from the Flettner rotor is shown to be smaller than that from the towing kite while, due to the different dependencies on wind speed and direction, the average power contribution from a Flettner rotor is higher than that from the kite on some routes and lower on others. While for most forms of international cargo shipping wind may not be suitable as the sole source of propulsive energy, a comparison of average output to main engine power requirements of typical vessels serving the routes indicates that it could deliver a significant share. For instance, installing three Flettner rotors on a 5500dwt general cargo carrier could, on average, provide more than half of the power required by the main engine under typical slow steaming conditions. Uncertainties and simplifying assumptions underlying the model analysis are discussed and implications of the results are considered in light of the urgent need for decarbonisation. This paper demonstrates the significant opportunities for step jump emissions reductions that wind technologies have to offer. It outlines next steps towards realising the potential, highlighting a demand for more detailed studies on socio-economic and technical barriers to implementation, and providing a basis for research into step-change emissions reductions in the shipping sector.

Grass silage making by direct cutting using a Corner Machinery-1300 flail forage harvester

This study presents two-year results on the performance of the Corner Machinery Type 1300 flail forage harvester during the first-cut grass silage making process. The experiment was conducted on a family farm in Western Serbia, on a 3.8 ha plot of sown grassland producing a grass yield of 25.5 to 29.20 t ha-1. The harvester was drawn by a 35 kW Ursus 3512 tractor. Under field operating conditions, at an average operating speed of 2.156 km h-1, the harvester achieved throughput capacity of about 7 t h-1 and a cutting efficiency of 0.176 ha h-1 depending on operating speed, cutting width, yield, plot size and work organisation. The average fuel consumption and energy requirement were 16.02 L ha-1 and 764.154 MJ ha-1, respectively. Due to simultaneous mowing, chopping and loading of the forage material into a trailer, the harvester had a high engine power requirement of 28.69 kW m-1 relative to the cutting width. During the ensiling operation, working time requirement was highest for forage cutting and loading (52.89%), followed by transport of loaded trailers (17.80%) and transport of unloaded trailers (15.87%). The harvester showed satisfactory performance as chop length was mostly below 50 mm on average in about 58.25% of the plant material, this value being in agreement with livestock nutritionists’ recommendations. During silage making from different plants on small family farms, the harvester achieved reliability and satisfactory performance, without coming to standstills due to breakdowns. Key words: Grass silage, forage harvester, performance, operating speed, efficiency, fuel consumption.

상용차용 변속기 기어의 경량화

Transmission is one of the important pars to transmit power from engine to wheels. Mass reduction gears can make the engine power requirement reduce, and can make dynamic performance and fuel efficiency of vehicle improve. Transmission gears are modified for mass reduction without changing their tooth shapes, face widths, and modules by using shape<BR>optimization and re-check process. Also structural stability is verified by FEA.

베일러 작업 시 트랙터 소요동력 분석

Purpose of this study was to analyze power requirement of an agricultural tractor for baler operation. First, a power measurement system was developed and installed in a 75 kW agricultural tractor. Strain-gages with a telemetry system were used to measure torques of transmission and PTO input shafts. An engine tachometer was used to measure rotational speed of transmission and PTO input shafts. The measurement system also included pressure sensors to measure pressure of hydraulic pumps, an I/O interface to acquire the sensor signals, and an embedded system to determine power requirements. Second, field experiments were conducted at two PTO speed levels, and proportion of utilization ratio of rated engine power and power consumption of major parts (transmission input shaft, PTO input shaft, main hydraulic pump, and auxiliary hydraulic pump) were analyzed. Results of usage proportion of engine power for PTO speed level 1 and 2 were 4.1 and 2.2%, 31.5 and 16.3%, 49.6 and 59.7%, 14.4 and 20.8%, and 0.4 and 1.0%, respectively, for ratio of measured engine power to rated engine power of less than 25%, 25 ~ 50%, 50 ~ 75%, 75 ~ 100%, and greater than 100%. The results showed that the usage proportion increased in the range with the ratio of power requirement to rated engine power of over than 50% when the PTO gear was shifted from P1 to P2. Averaged engine power requirement for baling operation, tying and discharging operation, and total operation were 43.3, 37.3, and 42.0 kW and 49.0, 37.0, and 47.4 kW, respectively, for PTO speed level 1 and 2. Paired t-test showed significant difference in power consumption of engine, transmission input shaft, and PTO input shaft for different PTO speed levels. Therefore, the power consumption of engine for baler operation increased when the PTO gear was shifted from P1 to P2. It was indicated that the power requirement of tractor was affected by the PTO rotational speed for baler operation.

Comparisons on engine power requirements of 6WD and 4WD prime movers for the oil palm plantation in Malaysia

An attempt was made to investigate the possibility of designing and developing a multipurpose, all terrain, 6WD prime mover for the oil palm plantation in Malaysia. Comparisons were made on the engine power requirements of the 6WD prime mover over the 4WD prime mover on four different soil classifications having terrain slopes ranging from 0° to 30° based on the traction equations by ASABE [1]. Generally, the 6WD prime mover showed in the range of 5.27–45.81% reduction in the engine power requirements than the 4WD prime mover having equal size and weight configurations when traversing over the four different soil classifications. Greater percentage reductions in engine power with the 6WD over the 4WD prime mover were found as the terrain changes from concrete to soft or sandy soil classification with prominent percentage reductions at higher terrain slopes. The proposed 6WD prime mover has a single chassis with skid steer drive wheels, oscillating drive axles, and low inflation pressure tires. The 63 kW water-cooled, diesel engine was sufficient to run an hydrostatic main pump at a working pressure of 220 bar and a flow rate of 91 L/min under two drive speeds (i.e. high and low) and two drive modes (i.e. forward and reverse). Proper prime mover wheelbase and proper ground clearance height were employed to give better stability and manoeuvrability for the typical oil palm plantation terrain in Malaysia. Mounting provisions for the seedling transplanting, fertilizer applicator and the in-field fresh fruit bunches (FFB) collection–transportation were made on the prime mover.

Design Parameters Optimization Simulation of a Prototype Segmented Rubber Track Vehicle for Sepang Peat in Malaysia

This study describes a simulation model for studying the basic design parameters of a special rubber track vehicle with rigid link tracks system on Sepang peat terrain in Malaysia. The prototype parameters for a track system, including proper track width, ground contact length, pitch and grouser height, idler diameter and location, sprocket diameter and location, road-wheel diameter and geometrical arrangement, the ratio of the road-wheel spacing to track pitch and location of the center of gravity to ensure good tractive performance. The vehicle track width significantly affects the vehicle external motion resistance. The road-wheel spacing ensures the number of road-wheels and significantly affects the vehicle external motion resistance. The vehicle traveling speed affects the vehicle engine power requirement and vehicle steerability during turning on peat terrain. The simulated performance results such as vehicle average motion resistance coefficient of 6.8 to 7.9%, drawbar pull coefficient of 25.22 to 47% and the tractive efficiency of 74 to 77% for the vehicle slippage of 5 to 20% and indicate that the vehicle can meet the peat terrain field requirement with its optimal power consumption.

Rotor Dynamics and Helicopter Stability

High and Low Drag Helicopters. A parameter which has not hitherto received any attention is the value of the fuselage drag. For any particular helicopter the drag will depend on the extent to which it is carrying bulky external loads, and the top speed under the high drag condition will clearly be substantially reduced. It might therefore be thought that any investigation of the high drag helicopter at a value of? of, say, 0·3, would be unrealistic since, for one thing, the engine power requirements would be inordinately high, and for another, the rotor blades would be very severely stalled. However, such an investigation is not, in fact, valueless, and we shall find a posteriori, that although the high speed case is effectively an idealised one, it will nevertheless serve the purpose of throwing up in a much emphasised form certain (apparent) discrepancies, which, in the low drag case, would hardly have merited attention. In the high drag case, however, the discrepancies cannot be dismissed so lightly, and we shall be obliged to investigate their cause. In so doing we shall obtain a much greater understanding of the underlying physical phenomena.