How can drag impact your train?

How can drag impact your train?

Due to the existence of train aerodynamic drag and wheel-rail friction drag, the velocity of the train model decreases as the train moves along the track without power. According to Eq (7), the stagnation pressure of the train model decreases with the running time, as shown in Fig 6.

How fast can a train accelerate?

The final factor and one frequently overlooked is the tractive effort required for acceleration of the train. It takes about 10 pounds per ton to accelerate to a speed of 6 miles per hour in one minute or 12 miles per hour in two minutes, a reasonable rate for a heavy train.

How is a train streamlined and overcoming drag?

In order to reduce the aerodynamic drag, adopting streamline shape of train is the most effective measure. The velocity of the train is related to its length and shape. The outer wind shields can reduce train’s air drag by about 15%.

What is the train resistance?

Trains resistance is defined in terms of force required to encounter resistance arising due to vehicle, track, grade, curve, acceleration, wind at different time and place etc. Primarily, train Resistance is bifurcated into internal and external resistance.

What factors affect the drag force on a high speed train?

Answer: Drag is influenced by other factors including shape, texture, viscosity (which results in viscous drag or skin friction ), compressibility, lift (which causes induced drag ), boundary layer separation, and so on.

Do trains have drag?

Pressure drag of train is the force caused by the pressure distribution on the train along the reverse running direction. The velocity of the train is related to its length and shape. The outer wind shields can reduce train’s air drag by about 15%.

Do trains go slower in the rain?

This is because when it rains, the tracks get wet. And trains will require a longer braking distance when the tracks are wet – just like road vehicles on wet roads. To compensate for the longer stopping distance, trains go slower. The rain does not affect underground lines.

What is the most aerodynamic train?

The results indicate that aerodynamic performance is influenced by the shapes of head and tail within high speed train. Symmetrical configuration with R head and R tail has the largest aerodynamic drag, while symmetrical configuration with S head and S tail has the least aerodynamic drag.

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 a grade resistance?

Grade resistance is the simplest form of resistance. It is the gravitational force acting on the vehicle. This force may not be exactly perpendicular to the roadway surface, especially in situations when a grade is present.

Why does the resistance of a train go up in winter?

During winter, the starting resistance goes up due to low temperature and higher bearing friction. The resistance due to this cause is directly proportional to the speed of the vehicle. Even on tangent track, the flange of the wheel touches the inner face of the rail in a sinusoidal motion thus creating a retarding force due to sliding friction.

How does the track affect the acceleration of a train?

At any moment, the track is having dips and ups on which the wheel is moving. This absorbs some energy and adds to the resistance. The amplitude of dips is small in case of well cushioned ballast track and so the track resistance as compared to ballast deficient track, loose joints etc.

How to calculate acceleration resistance on a train?

Resistance due to acceleration. This is the force exerted by the locomotive to accelerate the rolling stock and calculated as per Newton Second Law of Motion. F a =Accelerating Force=ma; or = W*a Newton; Where W is weight of train and locomotive in tonne and a is acceleration in m/sec 2. And also expressed in Tonnef as.

How does aerodynamics affect the design of a train?

In the context of modern, high-speed trains, this means mitigating the impact of aerodynamic drag on locomotives and rolling stock in order to save energy and fuel, while at the same time optimising operational efficiency and safety (the latter primarily focusing on stability in cross-winds and at high speeds).