Traction motor used for traction purpose is dc series motor, separately excited dc series motor, three phase induction motor, synchronous motor and permanent magnet synchronous motor. Some areas of improvement give even higher gains when combining them with others. Figure shows how velocity ratio and pull ratio combine for overall tractive efficiency. E6 the train decelarates to standstill due to the acting of the resistances fwa and fwl. Part of the gross traction is required to overcome motion resistance mr, which is the resistance. All the files you upload as well as merged pdf will be deleted permanently within a few minutes. Making connections allows electrons to flow, but internal resistance within battery delivers incrementally less than 12 v. Design, manufacture and sales of pedestrian operated battery powered tug units. See appendix b for a clipping from the teloc 1500 manual and formulas for. This differs significantly from the first sentence and a half of the wiki article.
May 11, 2007 rolling resistance 140n per kg frontal area 2msquared drag coefficient 0. An important factor in determining the continuous tractive effort of any vehicle with an electric transmission especially dieselelectric. Measuring traction power and rolling resistance of model. The speed at which both forces are equal is the maximum speed the train can get to on a flat piece of track. Part of the mechanical rolling resistance dependent on the first power of the. Rolling resistance, sometimes called rolling friction or rolling drag, is the force resisting the. Aug 22, 2018 built with the same core features as all our tractive gps devices, the tractive gps xl is more powerful than any other. Apr 02, 20 homework statement ascending a 1 in 10 hill, a 1500 kg car slows down from 100 kmh to 50 kmh in a distance of 400 m.
Full text of the tractive resistance of a 28ton electric. There are, of course, many such forces aero drag, hydraulic losses in the. Click here to see list of references, authorities, sources and geographical terms as used in this glossary. Road surface influence on rolling resistance semantic scholar. The potential difference across a real source is not equal to emf. Generation of equivalent driving cycles using markov. Tractive resistance wheel, axle, friction, varies, road.
Our machines can be used by a single operative meaning you can streamline production and increase productivity while. Chapter 25 current, resistance and electromotive force current resistivity resistance electromotive force and circuits energy and power in electric circuits theory of metallic conduction. Tractive effort is the force needed to simply move the train. Fasteners the term used when bolts, screws and studs are considered all together that conform to the requirements of this part of iso 898 are evaluated at that ambient temperature range. May 12, 20 whatever may be source or principle of working of traction motor, all provide tractive effort characteristics to encounter train resistance and provide acceleration. Resistance is a natural reaction to change, and it can take many forms. The speed at which both forces are equal is the maximum speed. This definition of rrc is possible to combine with a wheel which is. Tractiveforce hi and tractive efficiency tei corresponding to soil 1 1. Chapter 25 current, resistance and electromotive force. Pdf influence of locomotive tractive effort on the forces. Durant, cce, cpa the increased pace of change that many of us have encountered over the past ten years has been dramatic. The tractive effort of any locomotive is speed dependent and can be expressed with a table, a graph or a formula. Tractive effort and tractive resistance c12 abstract.
As used in mechanical engineering, the term tractive force is the pulling or pushing force exerted by a vehicle on another vehicle or. W weight or vertical force between wheel and surface n, lb f m mass on the wheel kg, slugs a g acceleration of. Tractive efficiency of a tracked vehicle sciencedirect. Apr 12, 2016 some of the factors relating to road surface like road roughness, tire wear, tractive resistance, noise, light reflection, electrostatic properties etc. Pdf evaluation of the performance potential of an automotive conceptual design. The resistance of the hub to turning on the axle is the same as that of a journal revolving in its bearing, and has nothing to. I actually study transport tycoon at university level and ive done the tractive effort calculations. What makes the tractive gps xl stand out from the crowd is longlife battery lasting up to 6 weeks on one single charge. If the rear wheels of the vehicle in the figure are driven with no slip taking place between the tires and the level road surface, the wheel force or the tractive effort te is equal to the torque at the driven wheels t w divided by the rolling radius or effective radius r w. It has the same tracking capabilities as the tractive gps and the tractive gps 2.
So lets supose there is a train in certain conditions that makes a resistance force of say 100 000 lbs, and you have a locomotive that has starting tractive effort of 100 000 lbs, and continuous of 60 000 lbs. Im assuming power is how quickly the train will accelerate and tractive effort is ability to climb hills, but im not sure. In order to start a train and accelerate it to a given speed, the locomotives must develop sufficient tractive force to overcome the trains drag resistance to motion, which is a combination of inertia, axle bearing friction, the friction of the wheels on the rails which is substantially greater on curved track than on tangent track, and the force of gravity if on a grade. W weight or vertical force between wheel and surface n, lb f m mass on. This is in contrast to power, which is a measure of the amount of, well, power. Rolling resistance modelling redirect to new location. Tyre modelling for rolling resistance chalmers publication library. Tractive power corporation innovative solutions for the. What is the difference in tractive effort and power in the locomotive stats. Thus the starting tractive effort is ususlly a function of the weight of the locomotive and the adhesion.
The total tractive force, ft, at the wheels for at roads consists of aerodynamic resistance, f air, rolling resistance, f. Traction can be defined as the friction between a drive wheel and the surface it moves upon. Internal resistance in a battery, you only get 12 v when it isnt connected. A typical high speed train te versus speed diagram is shown below. The tractive effort required to move a train consists of numerous factors, but for most applications only four need to be considered. It was recommended that for indicated 1932, the author developed constants for a new m ethod of figuring horsepower and tractive effort of steam locom o. Tractive effort is a measurement for the amount of force that a train can put on the track. This energy wears the tires and compacts the soil to a degree that may cause detrimental crop production burt et al. A wheel will have different traction on different surfaces, as, the coefficient. In general, the best tractive performance and the most uniform ground pressure on a belt drive can be obtained with a dynamic balance ratio of near 50%. Full text of the tractive resistance of a 28ton electric car see other formats i a 5,v. Gradient modelling with calibrated train performance models.
Tractive effort determines how much a locomotive can haul. Some of the factors relating to road surface like road roughness, tire wear, tractive resistance. In order to generate this tractive effort we need two. Mechanics net tractive force question physics forums. Sep 22, 2006 tractive effort determines how much a locomotive can haul. For slopes, you will need an additional 100 newton per percent of steepness. F traction effort or force acting on the wheel from the surface n, lb f. The merge was done by selecting the highest measured value of tractive effort for the given speed. Tractive effort versus horsepower trains magazine trains.
Calculate the net tractive force f between the tyres and the road assuming f remains constant and wind resistance can be neglected. It is the amount of force a wheel can apply to a surface before it slips. Innovative method for measuring the tractive effort of. Tractive force is the force used for generate the variation between tangential surface and body. While resistance to change has been usually conceived as a quintessential human response, individuals may have different reasons for their resistant behaviors.
Built with the same core features as all our tractive gps devices, the tractive gps xl is more powerful than any other. Tractive effort and resistance to motion tractive effort resistance to motion i have extended the speed range on the graph to show the point where the resistance to motion gets larger than the tractive effort. Influence of locomotive tractive effort on the forces between wheel and rail article pdf available in vehicle system dynamics 35supplement. Pdf vehicle tractive force prediction with robust and windupstable. The resistance of the hub to turning on the axle is the same as that of a journal revolving in its bearing, and has nothing to do with the condition of the road surface. Driving resistance analysis of long haulage trucks at volvo. The maximum permissible traction force that can be applied to the wheels is governed by two things.
The resistance to motion due to friction per unit weight hauled. Pdf influence of locomotive tractive effort on the. More specifically, the rolling resistance modelling concerned the relation between road. Tractive effort of steam locomotives locomotive ratiosii. Ab this is constant tractive effort line generally up to a speed of 3050kmph. The rolling resistance is essentially a just a force acting on the vehicle, which has to be overcome by the engine. Tractive effort of steam locomotives locomotive ratiosii by a. Tractive force calculation for a vehicle tractive force or tractive effort or traction is the force applied between the tire and road surface to move a car or any vehicle for that matter.
I suggest merging this article in to traction engineering, as that title covers this and other topics please see talk. Online identification of running resistance and available. Tractive power corporation is a manufacturing, design and engineering company for industrial rail products and technology solutions. First, a force of 2 to 5 pounds per ton of train weight is. Definitionofterms,bythetermsresistance,train resistance, and carresistance used in this bulletin is meant the number of pounds oftractive effort requiredatthe rims ofthedriving. So if we look at an ac6000 compared to an ac4400, assuming the weight, traction motors and gear ratio are all the same, they are likely to haul the same load over a given. For a given tractive effort, increased horsepower allows an increased speed with other things remaining the same. The actual tractive effort curve then ususlly becomes a force increasing as speed decreases until the curve crosses the adhesion limit line which creates a. During the late 1980s, many of us were grappling with issues that we. Tractive effort definition is the force in pounds exerted by powered equipment as a locomotive as measured for statistical purposes at the rim of the driving wheels. Tractive effort te and tractive resistance tr tractive effort te. When you need machines to assist with the lifting and moving of products and equipment on an industrial scale tractive power has the solution.
Pdf estimation of the rolling resistance of tires researchgate. Then press the merge button to get your merged pdf. Tractive effort definition of tractive effort by merriam. Research shows that about 20% to 55% of the available tractor energy is wasted at the tractive devicesoil interface. Or tractive force is nothing but the net force present at wheels. If a cross over the tractive effort curve would appear for the next gear by remaining in gear until maximum rpm, then a small, roughly triangular shaped section would be cut out of the available area every time when gear is changed. Tractive effort vs power a fundamental equation to convert power to tractive force or effort is shown below this equation can be modi. Tractive effort and tractive resistance c12 springerlink. Caculating tractive force i need a formula physics forums.
Pdf vehicle control systems need to prognosticate future vehicle states in order to improve energy. The tractive resistance of electric locomotives and cars. Pdf resistance to change in the case of mergers and. Power is the force needed to run a train at a certain speed. P is the power output delivered by the engine, t is the tractive force or effort, is the ef. Innovative method for measuring the tractive effort of rail. Note that at high speed, where the air turbulence resistance is very high, the tractive effort is by necessity low. Resistances, tractive effort, and alignment2500 tons of freight have to be moved by rail in conventional rail cars from city a to city b along the rail route shown below using dieselelectric locomotives 3000 gross hp. Is the maximum tractive effort of a vehicle dependent on. Given time these two spots will continue to enlarge merging into one another. First, a force of 2 to 5 pounds per ton of train weight is required to move on straight level track. From the point of view of tractive effort and traction dynamics the creep law for bad adhesion conditions is of main importance.
So our first guess at a tevsspeed curve is a hyperbola. Tractive efficiency te versus tractive force h for soil 1 366 tractive efficiency of a tracked vehicle l225 m and track width s0444 m. Most early models only crudely approximate tire rolling resistance behavior over a. The resistance to traction of a vehicle on aroad consists of three independent elements. By the way, the term tractive effort is supposed to imply at the wheel rim, as opposed to at the locomotive coupler. Mr motion resistance w weight, static wd weight, dynamic slr loaded radius, static rr rolling radius rt torque radius eh figure 4. Tractive efforts is defined as the tractive force of a vehicle exerts on a surface or the amount of tractive force is parallel to the direction of motor. Rl i 11 1914 universit illinois bulletin issued vol. The tractive resistance of electric locomotives and cars davis, william on. Big, bigger, tractive gps xl tractive blog dogtracker. Homework statement ascending a 1 in 10 hill, a 1500 kg car slows down from 100 kmh to 50 kmh in a distance of 400 m.
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