LABELLED "the world's most stunning train," much of the striking design of Trenitalia's new flagship high-speed train, the Frecciarossa 1000, is traceable to a humble sketch drawn by the company's CEO.
Dr Alexander Orellano, head of vehicle design at Bombardier Transportation, says one day during the early stages of the development process Mr Mauro Moretti handed their development team a drawing and told them that he wanted the new train to resemble a Cobra.
"While of course it was clear that some things wouldn't work, the overall concept was pretty good," Orellano says. "He gave us a very clear picture of how he would like the train to look and in many ways he is the guy behind it. We felt that adapting the idea of the leader of Trenitalia could tie us to the emotional perception of the train in Italy which would be so important."
As the first of 50 trains ordered from a joint venture of Bombardier and AnsaldoBreda, which secured a €1.54bn contract in July 2010, begins preliminary testing at Bombardier's plant in Vado Ligure, Italy, it is evident in the salient curves in the nose of the train that this original concept has made it all the way to the finished article.
Of course while the design is certainly aesthetically pleasing, getting it right is crucial to running a train efficiently and effectively at a maximum design speed of 400km/h.
"In 2008 we sat down and looked at what we needed to do to grow our presence in the high-speed market, because at that point we were not perceived as a big high-speed train supplier," Orellano says. "We felt that it was natural to become competitive in train performance because we couldn't beat our competitors on cost because they were in a position to mass produce a TGV or an ICE. We looked at putting our energy in the area of aerodynamics and energy performance. We decided to use optimisation methods based on generic algorithms related to cross-wind stability and aerodynamic resistance that would make our high-speed trains attractive and potentially position us at number one in this area."
For its €653m share of the contract Bombardier is responsible for concept and detailed design of the Frecciarossa 1000, or Zefiro V300, as well as certification, project management and the supply of propulsion equipment and bogies. AnsaldoBreda is supplying the car bodies and carrying out final assembly.
The train is 202m-long and is formed of eight cars with capacity for 469 passengers, and can be operated in single or double units. The sets have a maximum output of 9.8MW using 16 asynchronous motors that are powered from 25kV 50Hz, 3kV dc, and 1.5kV dc, with an option for 15kV 16.67Hz.
Research and development of the new train was aided by the German Aerospace Institute (DLR) under a cooperative agreement signed with Bombardier in 2009. The partnership focuses on researching the relationship of aerodynamics and aeroacoustics, dynamic stability, interior trends and interior acoustics with high-speed trains and has had a major impact on the final design of the Frecciarossa 1000 and the Zefiro 380 for China, Bombardier's inaugural very-high-speed train project. The two parties shared personnel during the development process and integrated the results of tests using DLR's equipment with Bombardier's simulation and CAD modelling tools.
Managing and reducing overall energy consumption is a major element of this design and development process.
Orellano says that although Trenitalia places less emphasis on this than private operators - for instance by declining to introduce technologies to reduce energy consumption while the train is parked which are possible but more complicated to implement - research carried out is likely to have a major impact on future variants of the Zefiro V300 and other rolling stock. Orellano says this is already evident in double-deck tilting emus Bombardier is developing for Swiss Federal Railways (SBB).
"When we started with energy performance in 2006 it was obvious to me that energy performance would play a bigger and bigger role in train design," he says. "But we faced the dilemma of developing an energy performance calculation tool which could consider isolated components developed by internal third parties and how adjusting any one of them would impact the overall train and its performance."
Orellano says that for example it is well known that increasing the size of transformers will reduce their energy consumption. However, replacing a two-tonne transformer with one that weighs four tonnes will impact overall energy consumption due to an increase in weight.
Bombardier has subsequently introduced a tool known as Train Energy Performance (TEP) which calculates overall energy consumption and performance and is now accessible to employees working on developing trains for all over the world.
Orellano says that engineers used the tool for the Zefiro 380 and inevitably many of the technologies used in this train have been adapted for use in the Frecciarossa 1000. However, there have been some slight improvements to traction systems and brakes due to higher reliability requirements in Italy.
Orellano says that a major challenge when developing a high-speed train is to use a design that prevents the natural inclination of an object travelling at such high-speed under cross-wind conditions to take off. The nose of the train is rounded and at high-speeds the airflow passing over the carbody can provide sufficient lift to cause elevation. However, by adjusting the design and appearance of the edges of the nose it is possible to reduce this lift and in fact produce downforce which will actually increase the stability of the train. The strong edges which provide its Cobra-like appearance are therefore crucial to overall aerodynamic performance.
Acoustic dynamics
Of course operating a train efficiently at up to 360km/h is not just dependent on aerodynamics; high-speed trains can also make a significant amount of noise.
Orellano identifies the pantograph as one of the major sources of acoustic emission vibration as well as drag which resulted in a shift away from its traditional roof mount.
"The problem with placing the pantograph on the roof is that it vibrates a lot when the train is operating at high-speed," Orellano says. "The carbody's flat plate roof effectively vibrates like a drum. In older high-speed trains power cars were situated at either end so no-one was sitting below the pantograph. But in today's trains passengers are seated throughout so this has become more of a problem and is something we wanted to address."
The solution adopted for the Frecciarossa 1000 is to mount the pantograph directly to the sidewall of the carbody with the stiffness of the carbody and the curvature of the sidewall working to reduce the vibrations and as a result noise. In addition when the pantograph is not being used it is stored flat, again minimising vibrations and any impact on aerodynamics.
Another major source of aero acoustics is the deflection of air on to the front bogie. Bombardier supplied the bogies for the train which Orellano says are a conventional and proven design for high-speed trains. However, engineers adapted the nose to deflect air in front of rather than directly onto the bogie which is proving quite successful at reducing this noise.
The train is also using Bombardier's Active Lateral Suspension system in conjunction with a "hold off device" which aids performance through curves. When the train traverses a curve at high-speed the carbody might become overly positioned to the right or the left. The system works by automatically adjusting the position of the train to the centre which Orellano says improves the comfort of the ride and has allowed the use of a wider carbody while increasing cross-wind stability.
Orellano says managing heat produced from the train was another major consideration.
"We have built a train that consumes around 8MW of energy, all of which will be converted to heat," Orellano says. "So when it is in operation we had to be careful to use a design that prevents hot air which is passing through the cooler from being taken in as cool air in another device. We also took the external aerodynamics into account to identify where air might go at different cruising speeds and wind conditions with the aim of making sure that critical components are as cool as possible which is not good for reliability. Bearings for example are susceptible to changes in temperature so we wanted to avoid this effect."
Five trains of various configurations will be used for certification which began on the first set at Vado Ligure in April. Bombardier's project director Mr Franco Beretta says this is intended to "squeeze the testing process" to meet the completion date of September 2014. He says the first train will be ready immediately after the certification phase is finalised, with delivery of all 50 sets due to be completed by 2017.
The first train is currently undergoing preliminary testing and will be transferred to the Velim test track in the Czech Republic to begin dynamic tests in September. From the second train onwards all tests will be performed on Italian Rail Network (RFI) infrastructure.
The second train, which like the first is not yet a complete set, will certify the signalling, braking and traction systems as well as carry out harmonic tests. The third train will conduct running dynamics and test the pantographs' performance and will be involved in line testing which is due to start in mid-2014 on the Milan - Rome and Milan - Turin high-speed lines where 360km/h tests will take place. Three vehicles of the fourth set will test climatic performance in a climatic chamber at the Rail Tec Arsenal facility in Vienna between October and December, and will later test aero and acoustic dynamic performance. The fifth set will perform Technical Specification for Interoperability (TSI), EMC tests and along with the first train, will test the multi traction systems.
The contract with Trenitalia includes an option for securing a TSI for the train on international networks which would involve adjusting the pantograph and incorporating different signalling systems. Beretta says these options have not yet been exercised so this element of the project is not yet underway. But when it is he envisions that five to 10 of the trains could be adapted for operation outside of Italy.
Having a train that is operable on foreign networks would support potential bids from Trenitalia for high-speed concessions outside of its home market. Rumours are circulating that this is a future consideration for the Italian operator. And if they are found to have substance, Moretti's sketch might not just be a symbol of the future of Italian high-speed, but other networks in Europe as well.
