What do you mean by curve resistance?
Curve resistance is the added resistance or “drag” on a train that must be overcome by the tractive effort in rounding a curve. Resistance is usually measured in newtons per ton of train weight.
How do you find the resistance of a curve?
For example, in the USSR, the standard formula is Wr (curve resistance in parts per thousand or kgf/tonne) = 700/R where R is the radius of the curve in meters. Other countries often use the same formula, but with a different numerator-constant.
WHAT IS curve resistance in highway engineering?
The curve resistance is referred as when the passenger car is maneuvered to take the curve, the external forces acts on the front wheel of vehicles. These forces have components with the retarding effects on the forward movement of vehicles.
What type of curve is used for railway?
A track transition curve, or spiral easement, is a mathematically-calculated curve on a section of highway, or railroad track, in which a straight section changes into a curve. It is designed to prevent sudden changes in lateral (or centripetal) acceleration.
What is train resistance?
Train resistance, the force required to move a train, is the sum of the rolling resistance on tangent level track, grade resistance and curve resistance of the locomotives and cars. Other resistances due to wind velocity, tunnels or different train marshalling will not be discussed here. Rolling Resistance.
How is train resistance calculated?
Train resistance is calculated by multiplying the resistance per ton at each speed, by the total tonnage of the train.
What is vertical curve in railway?
The angle formed at the point of contact of the gradients is smoothened by providing a curve called the vertical curve in the vertical plane. Vertical Curves. An angle is formed at the point where two different gradients meet, forming a summit or a sag as explained in Fig. 13.18.
What is reverse curve in railway?
A ‘reverse curve’ is a curve to the left or right of the railway track which is followed immediately by another curve in the opposite direction because of which the speed of the trains need to be controlled at those points. This will help the Indian Railways to increase the speed of the trains on these routes.
What is super elevation in railway?
Superelevation or cant Superelevation or cant (Ca) is the difference in height between the outer and the inner rail on a curve. It is provided by gradually lifting the outer rail above the level of the inner rail. It is provided by gradually lifting the outer rail above the level of the inner rail.
What does curve resistance mean in railroad engineering?
In railroad engineering, curve resistance is a part of train resistance, namely the additional rolling resistance a train must overcome when travelling on a curved section of track.
How is train resistance related to track geometry?
Primarily, train Resistance is bifurcated into internal and external resistance. The internal resistance is internal to the train and prevailing track geometry over the entire train run.
Why does frictional resistance increase on curved track?
Track irregularities and load distribution influence the hunting causing frequency of sinusoidal motion and affecting resistance to the motion. This frictional resistance goes up on curved track and with increasing speed. So it is the lateral displacement of the wheel during the run and energy loss due to sliding friction results into this cause.
When does a train car round a curve?
If a train car rounds a curve at balancing speed such that the component of centrifugal force in the lateral direction (towards the outside of the curve and parallel with the plane of the track) is equal to the component of gravitational force in the opposite direction there is very little curve resistance.