CSU High Speed Train Group - The research group for the Tibet Railway Monash Visit 07-2007

CSU is a comprehensive and national key university under the direct administration of the Chinese Ministry of Education. It is located in Changsha, capital city of Hunan province, China.

The Key Laboratory of Traffic on the Track has for long engaged in the research on safety performance of trail transit and transportation. Their research focuses on two main fields. One is ‘trains aerodynamics’, which investigates all kinds of aerodynamic problems caused by high speed operating trains. The other is ‘trains multi-body coupling collision dynamics’, which improves passive safety level for crew and passengers. The laboratory is the major research base of Ministry of Railway for train aerodynamics, trains structure crashworthiness, streamlined head and structure design for high speed trains and trains operating safety evaluation.

The team has strong research strengths on high speed passenger trains and that of IRT towards freight, with a particular emphasis on carrying capacity of trains used in the resources industry. Several distinctive testing devices for train aerodynamics and structure impact were successfully developed, such as ‘Test equipment of moving train model simulating train’s aerodynamic performance’, and ‘energy-absorbing structure impact test system’. The laboratory has untaken a series of research projects on freight trains, high speed trains, maglev trains and subway vehicles from the government and companies. A design method for streamlined trains is developed, which covers train aerodynamic analysis, streamlined heads design, structures design and CAM. All streamlined heads of trains manufactured in china are designed by the team.The team have also completed operating safety evaluation about all newly-made trains (including streamlined EMU, locomotive and freight trains) from the viewpoint of aerodynamics.

The Qinghai-Tibet Railway is the highest railway in the world. It runs from Beijing to Lhasa. The line includes the Tanggula Pass, at 5,072 m above sea level the world's highest rail track. The 1,338 m Fenghuoshan tunnel is the highest rail tunnel in the world, at 4,905 m above sea level. The 3,345-m Yangbajing tunnel is the longest tunnel on the line, it is 4,264 m above sea level, 80 kilometres north-west of Lhasa. More than 960 km, or over 80% of the railway, is at an altitude of more than 4,000 m. There are 675 bridges, totalling 159.88 km, and over half the length of the railway is laid on permafrost.

According to Tibet plateau weather records, strong winds (wind speed exceeds 17 meters per second) region ranges from WangKun to YangBaJing (average altitude above 4500 meters, covers 800 kilometres). Average days with strong winds per year exceed 100, such as TuoTuo River 167.8 days per year, AnDuo 148.8 days per year, WuDaoLiang 135.5 days per year. On the Qinghai-Tibet Railway, the section from WuDaoLiang to AnDuo is located in the center of plateau region with strong winds.

Strong winds threaten trains operating safety, which increase aerodynamic drag greatly and impair lateral stability of trains. Especially in some special wind circumstances, such as large bridges, embankments, high mountains passes etc., aerodynamic forces increase significantly, which may lead to trains derailment or capsizal. In order to guarantee passengers and goods safety, it is necessary to investigate the effects of strong crossing winds on trains operating safety.

In the course of study, four methods were adopted, including numerical simulation, wind tunnel test, on the spot investigation and theoretical analysis. Research content includes aerodynamic performance mechanism of trains under strong crossing winds and low air pressure, lateral stability of trains under strong winds, running velocity limits of trains under different track locations and wind speeds, monitoring & forecasting system of strong crossing winds.

In this system, track parameter, winds data and vehicle parameter are all transferred to Xining control center. The running velocity limits are calculated and fed back to operating trains.

After making great efforts, the team led by professor Tian has built up trains operating safeguard system of Qinghai-Tibet railway under strong winds, which provides powerful guarantee for Qinghai-Tibet railway.

The research work on High Speed Trains

When trains velocity improves, air drag of trains increases greatly. For traditional trains with bluff head, air drag covers 70% of total drag. When trains passing by each other or passing through tunnels at high speed, transient air pulse is produced, which the transient air pulse is so powerful that it makes passengers feeling a drumming in the ears and vomiting. Moving train model tests have advantage over wind tunnel tests and full-scale test, which can deal with trains passing by each other and trains passing through tunnels. Now the team have built up high-speed moving train model test equipment.

The laboratory is the only base for train aerodynamics of China Ministry of Railway. In the last ten years, professor Tian and her team have undertaken many projects related to train aerodynamics. Through almost ten years research, research system for trains aerodynamics have been set up, including numerical simulation, wind tunnel tests, moving train model tests, real train tests and theoretical analysis.

Through discussion with Professor John Sheridan, the parties found common interests in wind tunnel tests and CFD, and have reached an agreement on staff exchange. CSU will send two junior staff members from CSU to work at Monash for six months. Taking an engineering project about high-speed trains as background, supervised by Professor John, the two young researchers will carry out research work in wind tunnel and CFD, doing both research and experiments. Monash is now proceeding with the paperwork to bring these staff to join Monash.

The team expressed that the visit is a good beginning for cooperation between the Key Laboratory and Monash Engineering. The team is looking forward to strengthening and broadening the cooperation in the future through the persistent effort.

Monash Engineering is looking forward to having the CSU visiting researchers, and is hoping that they will reach productive results, and have great times at Monash. Monash also hope that the visit will deepen the understanding with each other, tighten the relationship between the two universities, and develop further collaboration projects and programs in the future.