Pdf the rolling resistance and tractive performance of a small. Tractive resistance wheel, axle, friction, varies, road. Tractive force shear stress method predicted shear stress performance. The tractive force equals the 1tieight of the volume of water above a unit area multiplied by the slope of the c nal.
Rolling resistance in haul truck operations vericom computers. Tractive effort using dalemberts principles physics forums. Tractive system interface maintenance manual ece 492 spring 2019 latest revision. Gps tracking on smartphone for your pet directly from the manufacturer no. To wds tractive force lbft2 lo w unit wt of water lbrt3 d depth ft s energy gradient. It is convenient to consider this force as acting in the horizontal direction. Prediction of road texture influence on rolling resistance materials. Tractive efficiency was highest for the worn tire without chains in all soil types. Oct 16, 2015 traction can be defined as the friction between a drive wheel and the surface it moves upon. The tractive resistance of electric locomotives and cars.
The exact location of your dog can be accessed directly via the free app. Tractive effort and tractive resistance c12 springerlink. Rolling resistance plays a critical role in fuel consumption of mining haul trucks. Dieselelectric traction has the following advantages. In order to generate this tractive effort we need two. There are many examples of objects experiencing rolling resistance. Application of cfd to rail car and locomotive aerodynamics.
This means that the locomotive must have at least 74. It is usually expressed in pounds the relation between tractive effort, rail horsepower, and speed in miles per hour is tractive effort 270 rail horsepower kg speed note. Tractive effort is the propelling force which a locomotive exerts at the rims of its driving wheels. Tianyu zhu, xiaonan chen, yuqiu zhang, hongbo du abstract this document is intended describe the current design of the tractive system interface and its intended use. The device which converts electrical energy to heat energy is termed a resistor and its ability to impede current is termed resistance. So resistance can be defined as the opposition to current caused by a. Tractive effort is measured in this manner on road tests since it is virtually impossible to measure tractive effort at the rail.
Tractive force studies of cohesive soils for design of earth canals by e. Since the data files were recorded for any periods of continuous engine operation, these. Resistors there is always some resistance in every circuit. To request this document in an alternative format call 65664718 or 1800 6573774 greater. The tractive resistance of electric locomotives and cars davis, william on. Tractive effort te and tractive resistance tr tractive effort te. 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. Fsae tractive team calculations university of utah. Sketch out your own crazy resistor network and see if you can calculate the equivalent resistance. The maximum tractive efficiency of tractors tested under various conditions varied from 40 percent for soft field conditions to 84 percent for smooth hard sod.
Driving resistances of lightduty vehicles in europe international. Traction can be defined as the friction between a drive wheel and the surface it moves upon. Many hours of research went into this portion of the design, in simple terms, a battery management system is capable of monitoringprotecting the battery, balancing cells, estimate state of charge, maximize performance and be able to report to users andor external devices. The tractive resistance on curves of a 28ton electric car. Rolling resistance is a force that opposes the motion when an object rolls along a surface.
Boxn air brake stock up to 5400 up to 45 tractive effort values in tonnes at various speeds speed kmph speed kmph table no. Mr motion resistance w weight, static wd weight, dynamic slr loaded radius, static rr rolling radius rt torque radius eh figure 4. A circuit is always made up of some wire, so there will be some resistance there. This resistance that is from the parts of the circuit itself especially the battery is called internal resistance. In other words, it is the sum of the tractive force and rolling effort on the road surface. Tractive effort is defined as the force at the rims or the outer edges of the driving wheels of moving trains.
Using the rough heat transfer calculations we formulated conditions for the cfd simulation. What is the proper definition of traction or tractive. The coefficient of rolling resistance of the truck tires varied from 0. Tractive system interface user manual sites at lafayette. Pdf rolling resistance measurement and model development.
Ab this is constant tractive effort line generally up to a speed of 3050kmph. 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. This force, which is simply the pull of water on the wetted area, is known as the tractive force chow, 1959 t. A wheel will have different traction on different surfaces. The tractive resistance on curves of a 28ton electric car by schmidt, edward c. 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. Click here to see list of references, authorities, sources and geographical terms as used in this glossary.
The resistance to motion due to friction per unit weight hauled. By potting power plugs and outer tube end brackets, bentec service loops are capable of withstanding harsh environments and the highest mechanical tractive forces. In many cases, measured tractive force exceeds the rated tractive force because the mean steam pressure. Macmillan a cone index the soil parameter for empirical prediction of tractive performance is based on the force kn to push a circular cone base area 0. The tractive power required to overcome the above axle friction for american carriages of the usual proportions is about 3 to 3i lb. Kistler portfolio includes individually manufactured components such as wheel rims and vehiclespecific adaptations, including. May 25, 2016 this feature is not available right now. Rearrange individual pages or entire files in the desired order. 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. The only circuits that come near to zero resistance are superconductors. Macmillan vi rolling motion resistance, r is the force opposing motion of the wheel that arises from the nonrecoverable energy expended in deforming the surface and wheel. Overview of geosynthetic materials, their characteristics. While resistance to change has been usually conceived as a quintessential human response, individuals may have different reasons for their resistant behaviors.
Even the battery has parts that offer resistance to the flow of electrons. Notice the squiggly line just before the positive terminal of the battery. Research shows that about 20% to 55% of the available tractor energy is wasted at the tractive devicesoil interface. Of the total primary power used in iowa 1930 in farm operations, tractors comprise 39. Overview of geosynthetic materials, their characteristics, applications, and design considerations jie han, professor, ph. Electric traction 1701 however, the steam locomotive suffers from the following disadvantages.
While cylinder tractive force and rail tractive force should ideally be the same, in reality there is frictional resistance in crossheads, crank pins, axle. Tires, traction, tractive performance, forestry tire chains, wear. Bulletin university of illinois at urbana champaign. This resistance that is from the parts of the circuit itself especially. Sep 09, 2015 introduction to highway transportation engineering, module 02. Speed conversion kmh equivalents in mmin mph equivalents in fpm kmh mmin kmh mmin mph fpm mph fpm 0. Influence of rolling resistance on co2 the international council on. Rolling resistance measurement and model development. What is the proper definition of traction or tractive force.
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. Whatever may be source or principle of working of traction motor, all provide tractive effort characteristics to encounter train resistance and provide acceleration. Other resistances due to wind velocity, tunnels or different train marshalling will not be discussed here. 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%. Tractive force when water flows in a channel, a force is developed that acts in the direction of flow on the channel bed. May 11, 2007 rolling resistance 140n per kg frontal area 2msquared drag coefficient 0. Rolling resistance in car tyres increases with increasing tyre defor. This energy wears the tires and compacts the soil to a degree that may cause detrimental crop production burt et al.
Documents, transportation research record, washington, dc. The tractive performance of a new tire, a worn tire, and a worn tire with forestry tire chains was measured in four. Pdf cultivations in paddy fields can take place with a wide range of surface conditions and soil moisture which can have a considerable effect. 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. Electrical resistance resistance r any device in a circuit which converts electrical energy into some other form impedes the current. A special coating material ensures high impact strength, oil and chemical resistance, ultraviolet resistance and low flammability. This internal resistance is usually drawn into a circuit diagram schematic as shown in figure 1. Work at least a dozen of the equivalent resistance practice problems on the web site, making sure you can get the correct answer each time.
Tractive effort values in tonnes at various speeds speed kmph trailing load in tonnes at kmh with dry condition 30 curve. To request this document in an alternative format call 65664718 or 18006573774 greater. Introduction to highway transportation engineering, module 02. The resistance to traction of a vehicle on aroad consists of three independent elements. Fsae tractive team the conditions for cooling are for the worst case heat generation scenario. Tractive effort definition of tractive effort by merriam. Caculating tractive force i need a formula physics forums. 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. The worst case is a full 30 amp draw from the battery pack, with an ambient temperature of 35c 95f. 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. The speed at which both forces are equal is the maximum speed.
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