%tunnel ventilation & expert services %Dr. Alexander Rudolf

HyperRapid(TM) (logo mark USPTO #90508639, KSA Patent #353196 under examination)

The run for the HyperLoop has reanimated the idea of a high-speed tube transportation system, like the Swissmetro, for which NUMSTA(R) was developed. Many simulations showed that the drag can be reduced with the pressure level but problems related to the aerodynamics still remain. The vehicle aerodynamics of this transportation mode can almost completely be blended out by reducing the pressure to a level near zero. This concept is called the HyperRapid, which shall distinguish this transport system from the Hyperloop and the Transrapid, whose proven technology shall be used for levitation and propulsion.

In the HyperRapid, there is no chocking (Kantrowitz Limit); it will allow traveling speeds well beyond the speed of sound in a liquid, i.e. 340 m/s in air, 970 m/s in Helium or 1200 m/s in Hydrogen. A first target is 1800 m/s, i.e. 6500 km/h.

The aerodynamic challenge of the HyperRapid is the generation and maintenance of an almost complete vacuum, which would allow the vehicle to travel like in the Thermosphere (about 200 km altitude). There are other challenges as well, such as the tube, the vehicle technology as well as safety and comfort aspects. I have developed technical solutions for this.

For investors who are interested to create the ultimate (in terms of low pressure and high speed) ground transportation mode, I am more than happy to discuss the development of the HyperRapid.

In 1994, I started my work on the SwissMetro and developed NUMSTA(R) , the most comprehensive simulation tool for the NUMerical Simulation of Tunnel Aerodynamics on the market. In the course of this project, I realized the central aerodynamic problem of high speed transportation in a partial vacuum is the air displacement around the vehicle. Hence, I suggested to place a turbine inside the vehicle and described the TurboSwissMetro in my PhD.

The most important result of my analyses on the Swissmetro with NUMSTA(R) was that the aerodynamic problems can be reduced with the pressure. However, the required power and the limiting aerodynamic effect of choking are not completely suppressed, which still results in an unacceptable high energy consumption above a certain speed.