High Speed Railways

Here is a physics research paper i wrote on High Speed Railways (bullet trains). Take a look at this paper for background information because I will be making a presentation to your class on bullet trains on Friday, September 16.

-Walter Hill

High Speed Railways

High Speed Railways (HSR), better known as “bullet trains,” have revolutionized transportation over the past half century. They use innovative technology ranging from electromagnetic devices to linear motors to allow passengers and cargo to travel efficiently and safely at high speeds. These bullet trains are being improved using Magnetic Levitation technology and propulsion systems to enhance their productivity and capabilities.

The bullet train was born in Japan in October of 1964 with the Shinkansen. The first train the Tokaido Shinkansen ran about 320 miles from Tokyo to Osaka. The early bullet trains ran with speeds up to 125 miles per hour (mph) (Railway-Technology). Since the Shinkansen bullet train, technology has improved to allow for higher speeds and to travel longer distances. Today, in Japan bullet trains run over 160 mph, over 200 mph in China, and are used to carry mail in France. HSR are also used for various purposes in the United States of America, mainly in Northeast cities like Baltimore, Washington DC, New York, and Philadelphia. HSR also offer many advantages over automobiles and airplanes. Bullet trains can carry more passengers than both modes of transportation and travel at faster speeds, and are more environmentally friendly. According to an article in the New York Times, HSR leave a significantly smaller carbon footprint than airplanes and automobiles (Glaeser).

The bullet train has an effective design to allow for the travel of long distances at high speeds. To be aerodynamic and minimize wind resistance, the bullet trains use a streamlined body design to allow travel at high speeds. The front cars of bullet trains resemble power noses similar to the nose of airplanes because they are extremely aerodynamic. The front car of the bullet train feature dome canopies that allow drivers extended forward vision. Bullet trains also have specialized technologies that allow passengers to have comfortable transportation. The cars of bullet trains sit on top of flatcars that use air springs to compress air and absorb wheel vibrations from the track. This technology does not allow wheel vibrations from the track to reach passenger and cargo cars. The cars on the bullet train are also soundproof so passengers will not hear track vibrations and wind resistance. (Web Japan).

To ensure safety on HSR, railways are carefully designed and have technology to allow travel at safe speeds. The railways of HSR are made of steel that are mounted on concrete blocks. Bullet trains use wide gauge tracks and do not feature any sharp curves for high speeds and maximum carrying capacity. The speeds of bullet trains are controlled by Automatic Train Control (ATC). ATC transmits information about speed from the railway to the driver to maintain travel at designated speeds. To prevent congestion and control HSR traffic Centralized Traffic Control (CTC) is used. CTC manages the time and distance between trains for safety. Another safety precaution that allows safe and smooth travel is that trains never cross tracks at the same level. (Web Japan).

To improve bullet trains in the future, Magnetic Levitation (Maglev) technology is being tested. Maglev uses electromagnetic fields to levitate, suspend, non-contacting vehicles. Two options for Maglev are electromagnetic suspension (EMS) and electrodynamics suspension (EDS). Major advances in electronic control systems have paved the way for EMS. It is an attractive force levitation system where electromagnets on the bullet train would interact with the railway. EMS will maintain air gaps between the train and railway preventing unwanted contact between them. The changing magnetic fields created by EMS will compensate for errors in air gaps caused by differences between weights on the bullet train and the railway. EDS is a repulsive force levitation system that would use magnets on the moving train to induce currents on the railway. The repulsive forces produced by currents would create stable vehicle support because of increased magnetic repulsion forces as the air gap decreases. The only complication with EDS is that its repulsive magnetic forces would not work until the bullet train is in motion. EDS has progressed because of advances in cryogenics and magnet technology. (Ferguson).

Advancements in linear motors are another future improvement for bullet trains. Today linear synchronous motor (LSM) and linear induction motor (LIM) are being tested as future propulsion systems for bullet trains. LSM, also known as “long stator” propulsion, uses winding on the railway to attain high speeds. LIM, “short stator” propulsion, uses onboard winding. While LSM is faster than LIM it is more expensive because of the construction needed with the system. On the other hand LIM would generate less revenue because of higher operating costs. Other alternatives motors in the works are a gas turbine or turboprop systems. (Ferguson).

High speed railways are an innovative and interesting mode of transportation. Their unique design makes them a safe, efficient, and fast. They are also more economically and environmentally friendly than automobiles and airplanes. With future improvements coming for their motors and the Maglev technology, bullet trains could soon become the most reliable transportation available around the world.

Works Cited

Ferguson, L Joe. "Maglev Technology." The Enterprise Center. 30 March 2011. http://www.theenterprisectr.org/high-speed-ground-transportation/maglev-technology.html.

Glaeser, Edward L. "How Big Are the Environmental Benefits of High-Speed Rail?" 12 August 2009. New York Times. 25 March 2011. http://economix.blogs.nytimes.com/2009/08/12/how-big-are-the-environmental-benefits-of-high-speed-rail.

"Shinkansen High-Speed 'Bullet Train'." Railway-Technology. 4 April 2011. http://www.railway-technology.com/projects/shinkansen.

"Train Technologies." Hi Tech Bullet Train. 31 March 2011.

http://web-japan.org/kidsweb/hitech/shinkansen/shinkansen02.html.