Hydrogen Powered Rotaries

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Hydrogen Powered Rotaries

• By Bart Kapka

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Hydrogen fueled Wankel Rotary Combustion Engines

• Hydrogen burns to produce water. Hydrogen is
  relatively safe because it vents upwards.
  Gasoline (petrol) is more dangerous because its
  vapors creep along the ground and pool in engine
  bays and around tanks. New multiple evidence
  conclusively shows that the Hindenburg burned
  because its outer cover ignited and burned before
  any hydrogen and faster than the hydrogen

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Evaluation of the hydrogen fueled rotary engine
for hybrid vehicle applications

• The hydrogen-fueled engine has been identified as
  a viable power unit for ultra-low emission
  series-hybrid vehicles. The Wankel engine is
  particularly well suited to the use of hydrogen
  fuel, since its design minimizes most of the
  combustion difficulties

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Evaluation of the hydrogen fueled rotary engine

• In order to evaluate the possibilities offered by
  the hydrogen fueled rotary engine, dynamometer
  tests were conducted with a small (2.2 kW) Wankel
  engine fueled with hydrogen. Preliminary results
  show an absence of the combustion difficulties
  present with hydrogen-fueled homogeneous charge
  piston engines.

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Evaluation of the hydrogen fueled rotary engine

• Since the rotary engine has a characteristically
  high power to weight ratio and a small volume per
  unit power compared to the piston engine,
  operating a rotary engine on hydrogen and
  derating the power output could yield an engine
  with extremely low emissions which still has
  weight and volume characteristics comparable to a
  gasoline-fueled piston engine. Finally, since
  engine weight and volume affect vehicle design,
  and consequently in-use vehicle power
  requirements, those factors, as well as engine
  efficiency, must be taken into account in
  evaluating overall hybrid vehicle efficiency.

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The Search for Low-pollution Vehicles Continues

• Mazda began a two year trial period for its
  experimental low-pollution hydrogen rotary engine
  (RE) vehicle in 1995. The Cappella Cargo van
  model vehicle will burn a hydrogen fuel that when
  burned will not emit carbon dioxide. Mazda lent
  the vehicle to the Hirohata Steel Mill for use as
  their company van and drove it for at least
  20,000 kilometers on public roads. The fuel was
  stored as metal hydride. Some metal hydrides can
  store even more volume than liquid hydrogen.

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Hydrogen Car

• Inside the hydrogen car, everything is standard
  apart from a small pressure instrument - the fuel
  gauge... Starting the hydrogen car is no
  different from starting the petrol model, and
  engine noise sounds familiar too.
• The intake system combines a pre-mix air/fuel
  system for light load driving... There is also a
  direct-injection system through a dedicated
  hydrogen port which opens when the air intake
  port is closed. This is effective in increasing
  available power for higher speed driving.
• When the fuel pressure gets low, the power drops
  noticeably and the car slows dramatically.
  Changing down the gears makes little or no
  appreciable difference and even with 20 percent
  pressure available, the car is effectively unable
  to carry on. Refuelling these prototypes takes
  about 15 minutes from start to finish.

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Electric Car

• The electric car is completely different. There
  is very little engine braking so you have to
  start using the brakes much earlier than normal.
  And the engine is virtually silent, which make
  tire and wind noise much more apparent. Battery
  technology is holding up the whole electric car
  movement. Development has failed to produce a
  satisfactory alternative to nickel cadmium
  batteries (like those in the Mazda) or the
  standard lead acid type which cause so many of
  the problems. They make electric cars heavy,
  expensive, and poor performers, with very few
  miles possible between each lengthy charge-up.
• Mazda is investing much more heavily in hydrogen
  research than electricity.

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Fuel of the Future

• HR-X1 not hydride, 2 seat, spacy commuter look.
• HR-X2 metal hydride, 4 seat, dowdy.
• MX-5 metal hydride, Miata body, front twin rotor,
  rear drive.

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Mazda Advances Environmentally-Correct HR-X
Powered by Hydrogen

• The refined Mazda HR-X . is a concept car that
  runs on pure, renewable hydrogen, and emits
  primarily only water vapor. It has been improved
  since its original debut in 1991 by Mazda
  engineers to improve its performance and increase
  its fuel efficiency. The Mazda vehicle shows that
  hydrogen can be safely used as a fuel.

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• The metal hydride tank is shown being fueled
  below, with one hydrogen fuel line, and two lines
  which run cooling water through the tank. During
  refueling, the metal hydride in the tank warms as
  it absorbs hydrogen, and the water cools it to
  allow more to be absorbed. When the engine is
  running, the warm engine coolant water is
  circulated through the tank to warm the metal
  hydride, causing the hydrogen fuel to be
  released.

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• Unlike piston-engines, the rotary engine has
  separate intake and combustion chambers. This
  allows the rotary engine to avoid the backfiring
  and preignition problems that other engines have
  experienced. The rotor draws the air and hydrogen
  in as it passes the top of the cycle, then moves
  the mixture to the lower right and compresses it,
  where it is ignited to drive the engine

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• The HR-X hydrogen car's rotary engine delivers
  100 horsepower, which is nearly the same as the
  original RX-7. This concept car, shown at the
  Tokyo Motor Show, and auto shows in New York and
  Los Angeles, has generated much excitement and
  public awareness of hydrogen as a fuel with
  today's technology. Mazda's break ahead of the
  other auto companies is truly an advancement to
  the solar hydrogen industry.

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HRX-2

• Mazda's HRX-2 "is powered by a hydrogen burning
  rotary engine and has a virutally 100 recyclable
  body structure. It's been developed with the
  potential to use liquid-crystal polymer
  fibre-reinforced plastic. This plastic is in the
  process of further research for practical use.
  The plastic-made upper-body can be easily
  detached from the metal chassis. The electrical
  and control systems are integrated into one area.
  Therefore, this structure makes it easier to
  disassemble the body and to sort, by material
  make-up.

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Stats Of HRX-2

• Gasoline
  Hydrogen Electric
• Power (HP) 120 110
• Top Speed kmh (mph) 183 (114) 150 (93)
  130 (81)
• 0-40 kmh (25 mph) sec 2.5 2.9
  4
• 0-100 kh (62 mph) sec 9.4 13.0
  21.5
• Refueling time 3 minute? 15
  minute hours?