Vande Bharat Express: Incremental change in Design with Incremental Change in Speed is the way Forward?

At a time when design as a subject is being percolated from core area like mechanical engineering to computer science and even Business schools have started flagship design thinking course in the country, ugly picture of much awaited Vande Bharath-2(VB2) express after just hitting cows/buffalos has left everyone stunned.

The official statement came like: The nose of the train has come out. As we say in Indian culture 'nose' is the pride of any thing person, has it shaken the the pride?

The inauguration of the superfast train has been done just a week before with much fanfare and three consecutive days problem occurred like Hat-trick in cricket:

On 6th of October: The Mumbai -Gandhinagar bound VB2 hit Buffalo and from panel of the engine came out with some some visible damage to the Train.

On 7th of October: The Mumbai -Gandhinagar bound VB2 hit cow and with a minor dent in the front pane and breaking of sacrificial nose of the Train damaged. In minutes time the train resume the journey and reached Gandhinagar at the scheduled time.

On 8th of October: New Delhi-Banaras bound VB2 came to complete halt due to bearing defect in traction motor.

Design Issues:

Compared to other trains like local, mail, express or Rajdhani, VB design has been completely changed. Not sure whether it is inspired by Japanese high speed trains or aerodynamic design of Aeroplane/Rocket or Missile.

Its a classical problem in optimal design to be objective function as lower the weight with constraints like higher strength, more stability etc. As width and height has to be same like other trains as these superfast trains also run on the same railway line and electric power source so finally there are only few things that could have been changed: Materials has be of lesser density, more impact resisting with cost shouldn't be very high.

With higher speed focus has to be given to be aerodynamic design. which we see here for the VB-2. Extra sacrificial Nose has been provided to maximize the energy absorption which can be detached to protect the rest of the train. So all the focus is on the nose that has been made of Fiber Reinforce Composite that is very common in the last 50 years in the automobile to aero plane design. Like a bumper and fender in a car ideally it should be design to absorb huge energy.

As weight of Vande Bharat express has been drastically reduced and speed increased to more than 150km/hr so stability and balancing are some other concerns.

Nose Cone is generally used when speed is in the range of high Mach Number. Speed above 100km/hr for a train is very common now a days so incremental change in design could have done the work rather going for Aeroplane, Rocket or Missile of high Mach Number type design

What cant be changed:

Fencing both sides of track is not practically possible in thousands of miles railway network spread in the country. Like mero train elevated track will be very expensive so it may not be feasible to build elevated track on the present rail line.

Dimension of the Bogies(width and height) can't be changed due to constraints of track width, platform design and electric power supply arrangement for the running train.

Conclusion:

As currently only 3 Vande Bharat Express-2(VB-2) train is running, before going for more production its right time to think about design and material changes of the front portion also weight reduction is another issue that should be considered before we hear some bad news like VB-2 is off track by hitting elephant or in the midst of powerful storm!

Shape memory alloy or smart material can be used to get away with the deformation and with multiple layer of sacrificial nose .train can be kept running even with minor accident.

The Front part of the engine with all the design and features like other trains with some incremental change can be the best way to keep the incremental change in design with incremental change in speed.