Scientists in China are working on a new maglev system which they believe could achieve remarkable speeds via the use of enclosed low-pressure tubes.
The project, led by Dr Deng Zigang from the Applied Superconductivity Laboratory of Southwest Jiaotong University, involves placing a maglev vehicle within a sealed vacuum tube, in order to radically enhance velocity via the reduction of air pressure and related drag.
Maglevs are among the fastest mass transit systems in existence, achieving their remarkable speeds via the use of powerful magnets to suspend vehicles just above their guidance rails. This dispenses with the need for wheels, axles and bearings, as well as the role of traction and friction for the purposes of acceleration or deceleration.
Air resistance, however, continues to hamper their efficiency and speed, with Deng estimating that 83 per cent of the traction energy of regular maglevs is dispersed by air resistance when running at velocities in excess of 400 kilometres per hour.
In a recent research paper, Deng concluded that the best expedient for dealing with this issue is to dramatically lower the atmospheric pressure of the running environment by containing the vehicle in an enclosed tube.
“Evacuated (airless) tubes…remove air drag and push the speed higher and higher,” Deng said.
Deng and his colleagues at Southwest Jiaotong concluded the first phase of a prototype project in February this year, by developing a high-temperature superconducting (HTS) maglev vehicle which is capable of accelerating to a set target speed of 25 kilometres per hour.
Their prototype runs along a modest ring-shaped guideway with a radius of just six metres, and a maximum speed of 50 kilometres while unmanned.
The researchers are now hard at work on the second phase of the project, which involves enclosing the ring line within a tube whose atmospheric pressure is 10 times lower than the normal reading at sea level in order to determine the effects on vehicle efficiency and speed.
Deng remains extremely confident about the project’s prospects for success.
“At this moment we are conducting tests on the new system,” said Deng. “We will release our achievements after the successful running in the future.”
According to Deng, the technology could soon enable maglev trains to achieve speeds which vastly surpass those of even the fastest current systems.
While the world’s fastest passenger train – the Shanghai Maglev which opened in 2004, is capable of achieving speeds as high as 431 kilometres per hour, Deng believes that the new HTS vehicles operating with evacuated tubes could attain velocities in a “new order of magnitude.”
He sees the technology enabling trains to run as fast as 3,000 kilometres an hour, which would open the door to either military or space launch applications.