The tractive effort required to overcome the force due to gravity. I need to know exactly what the difference is between traction and tractive force. This is specifically in reference to wheels and road surfaces. The continuous tractive effort would be determined by how much electricity traction motors could handle before burning up. 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. Tracktion music production technology audio editing.
Tractive effort curves show how much force the wheels can push forward on the rails with for any given speed. Models for estimating energy consumption of electric trai. Calculating tractive effort for steam locomotives when modeling a set of train vehicles, an important information needed for the dynamics of a locomotive is max tractive effort te, resp max te, which is determining the ability of a locomotive to pull up a train. Which basically means, from the blueprints, that is the effort it should be capable of producing. Above that speed, the locomotive doesnt have enough power to generate that much force, and is now following the formula fpv. Tractive effort and acceleration ce 322 transportation engineering dr. Tractive effort is the force needed to simply move the train.
Locomotive tractive effort and power calculations tractive effort calculations. Tracktion provides innovative software production tools for musicians, composers and songwriters. The attractiveness of some novel approaches like cryptographic key generation from. May 12, 20 tractive effort, when multiplied with speed at which the train is required to run, gives the horsepower. Im assuming power is how quickly the train will accelerate and tractive effort is ability to climb hills, but im not sure. Research shows that about 20% to 55% of the available tractor energy is wasted at the tractive devicesoil interface. Pdf calculation of the traction effort of switching locomotive. A locomotives tractive effort at all speeds is limited by its adhesive weight and the available coefficient of adhesion between wheel and rail, as illustrated in the above diagram and as discussed in more detail on the adhesion page of this website the maximum speed that a locomotive can attain with any given train occurs when the locomotives drawbar tractive effort exactly equals. Pdf on jan 1, 2012, anton rassolkin and others published calculation of the. But as i said, when you measure both at the same point, horsepower is speed times tractive effort divided by 375, with no qualifications. Traction force microscopy tfm derives maps of cellgenerated.
Traction modelling in train dynamics qing wu, maksym spiryagin. Traction effort of switching locomotive chme3 with railroad slope 0. To do this we will use the maximum tractive effort calculated in equation 9 which was 100 lbs. A number that relates to a tractive effort on a dc motor locomotive that the traction motor can obtain indefinitely without overheating. It is the amount of force a wheel can apply to a surface before it slips. Tractive effort is defined as the force at the rims or the outer edges of the driving wheels of moving trains.
Adhesion is the grip or force of attachment, produced by. Three cylinder locos are worked out differently from memory. Therefore, tractive effort was more important than horsepower for steam locomotives. The car has a mass of 4,000kg and the resistance to motion is 400n determine. In this paper, two models for estimating energy consumption of single train operation are presented. Power is the force needed to run a train at a certain speed. Nov 18, 2006 difference between traction and tractive force. First, a force of 2 to 5 pounds per ton of train weight is required to move on straight level track. The maximum permissible traction force that can be applied to the wheels is governed by two things. Tractive effort te and tractive resistance tr tractive effort te.
The tractive effort of a locomotive whether ac or dc is defined by the equations. Tractive effort of steam locomotives locomotive ratiosii by a. Preceding unsigned comment added by fengrail talk contribs 02. Calculating tractive effort for steam locomotives transport. Total tractive effect required for accelerating the train on a level track. For slopes, you will need an additional 100 newton per percent of steepness. Influence of locomotive tractive effort on the forces between wheel and rail.
Driving torque of mm of the traction electric motor by means of a. Above is a tractive effort curve typical of a new electric train. As with power, there are different methods of measuring tractive effort. Lets transfer fz force to a point of contact of a wheel with the t rail, having added forces equal to it fa. Starting tractive effort, found in the locomotive data sheet, is the rated tractive effort starting from a standstill in run8. The maximum traction effort co uld be calculated by 9 and 10 with respect to changing of the frictions forces with different atmosphere conditions dr y and wet surfaces. The primary advantages of ac traction are adhesion levels up to 100% greater than dc and much higher reliability and reduced maintenance requirements of ac traction motors. Cte is non applicable for an ac traction motor, which use te only. Instinctively it seems that they should also have better traction. If you find this website valuable and appreciate it is open and free for everybody. As the freeend of the band is pulled, the friction between the band. Jan 07, 20 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. To verify the proposed models, a real railway link and an electric train from taiwan railway administration tra are selected for the experiment. Joint effort s between the fluid power society fps and.
This overview paper outlines our views of actual security of biometric authentication and encryption systems. Available tractive effort road vehicle performance. Acceleration is a measure of how quickly you are gaining or losing speed. Calculating tractive force using two methods physics forums. The energy consumption estimated from the proposed model is then compared with that. With this in mind, there are two places we can get tractive effort. Ahmed abdelrahim available tractive effort tractive effort determined by. Files available from the acs website may be downloaded for.
Importance of tractive effort lies with its capability to start a train on the gradient and run it up to a speed of around 30 kmph whereas that of horse power is its ability to achieve and run at the maximum permissible speed. A car accelerates 1800m down an incline of 1 in 4 at 0. W weight or vertical force between wheel and surface n, lb f m mass on. A conceptually opposite approach is provided by referencefree methods, opening to the onthefly generation of force. The tractive effort required to move a train consists of numerous factors, but for most applications only four need to be considered. The traction force ft required at the drive wheels is made up of the driving resistance forces and is defined. F traction effort or force acting on the wheel from the surface n, lbf. Someone more experienced then i with steam may want to correct me here, but the forlmula you gave is for what would be known as the rated tractive effort. We now have the speed rpm and the required tractive effort. This is in contrast to power, which is a measure of the amount of, well, power. The traction threshold speed, where tractive effort is exactly high enough to make full use of engine power, can be calculated by solving for vpft, where ft is tractive effort, p power, and v velocity in ms kph3.
Tractive effort is a measure of the force that a locomotive can apply to the train it is pulling. Traction can be defined as the friction between a drive wheel and the surface it moves upon. Assume that the available tractive effort is the engine. New interpretation of process of formation of tractive effort of the. Force of vehicles engine maximum value transferable maximum tractive effort define the point at which additional enginegenerated tractive effort is not productive. The tractive effort is a product of the weight of the vehicle and the. Tractive effort of steam locomotives locomotive ratiosii. Locomotive tractive effort chart irwin car and equipment.
Wheel motors consist of a hydraulic motor mounted integrally with a wheel and tire assembly. Locomotive tractive effort chart based on weight and grade. This is a summary of what i think is the most important and insightful parts of the book. Tractive effort or tractive force is measured in kilonewtons kn or pounds force lbf where 1 kn 228. Pdf new interpretation of process of formation of tractive effort of. Tireground adhesion and maximum tractive effort the slip, s, of a tire is usually defined as where v is the translatory speed of the tire center. Calculating tractive effort page 1 locomotives and. I will wait a bit for clarification before making any alterations. Steam locomotive tractive effort vs diesel electric horsepower posted by isambard on thursday, june 3, 2004 12. The last step is to calculate the axle torque required to generate this tractive effort. In the main line train, tractive effort is caused by the locomotive, and in a suburban train, it is caused by motor coaches. Oct 06, 2016 if you measure tractive effort at the wheel rim, and horsepower somewhere else, then you have to estimate the losses between those two locations.
Tractive effort is a measurement for the amount of force that a train can put on the track. Horsepower and tractive effort the idiots guide to. As used in mechanical engineering, the term tractive force can either refer to the total traction a. For steam locomotives, tractive effort was usually the limitting factor in the size of the train it could pull. I can find definitions of traction but nothing really on tractive force. 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. Nov 10, 2016 what is the difference in tractive effort and power in the locomotive stats. The tractive force between a car wheel and the surface can be expressed as. Tractive effort definition of tractive effort by merriam.
In most cases, maximum tractive effort is developed at low speed and may be the same as the starting tractive effort. Ac traction for locomotives is a major improvement over the old dc systems. Common fixed points of locally contractive mappings in multiplicative metric spaces with application. Pdf influence of locomotive tractive effort on the forces. This may seem like a trivial distinction, but to a physicist power and force are very different quantities. Tractive effort and tractive resistance c12 springerlink.
Weight transfer due to torque exerted by traction motor. Weve made productivity easy with software for level 10 meetings, vto, accountability and more. Maximum tractive effort is defined as the highest tractive force that can be generated under any condition that is not injurious to the vehicle or machine. Jun 22, 2017 tractive effort te is the force applied by a locomotive for moving itself and a train. Pound force applied to the rear coupler to pull a train. Model 2 is improved from model 1 by empirically simulating locomotive sanding systems, variable track conditions and traction force reduction. The total axle torque is tractive effort times the wheel radius. When moving up in the slope the drive has to produce tractive effort to overcome the force due to gravity. Pdf common fixed points of locally contractive mappings. Steam locomotive tractive effort vs diesel electric. Assume that the available tractive effort is the enginegenerated tractive effort. Ac traction vs dc traction greenville, south carolina. From newtons second law using the equation above you can work out the equivalent accelerations to each tractive effort. The tractive force is the pulling force exerted by a vehicle, or machine or body tractive effort is a synonym of tractive force, used in railway engineering terminology when describing the pulling power of a locomotive.
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