Subject: Rotary engine
From: Rotary Engine
Date: 5/15/2009, 11:12 PM
To: AAA Put this in the To box


  Paul,
  Is this engine for real.  The video claims it won an award.
  http://www.youtube.com/watch?v=_MBYg1NPzMY&feature=related
  Doug in Japan

  No of course not :)


  -------- Original Message --------
  Subject: The MYT Engine
  Date: Thu, 24 Apr 2008 17:12:15 -0700
  From: Rotary Engine <rotaryeng@earthlink.net

  Paul & Group;
  What do you think about this Engine?....Is this for real?
  Thanks,
  Steve

  http://www.youtube.com/watch?v=u_pLQQDzStg

  That is nothing new. That is called a scissor engine
  and it has been around since at least 1925 maybe earlier.
  Norbye mentions it in his classic book "The Wankel Engine"
  published in 1971. Page 505

  Its not a rotary engine. It is scissor,  AKA cat and mouse engine,
  AKA Tschudi, AKA Kauertz invented years ago. It has a snow balls chance
  in hell of succeeding. It meets almost none of these criteria.

  There are a zillion of these things on youtube.
  The vast majority of the inventors  do not have a clue. Felix
  spent a lifetime on the Wankel and Mazda and others have spent
  billions perfecting it. Mazda has sold two million.

  None of these engines have a snow ball's chance in ****
  of ever making it into to production.



  By Kenichi Yamamoto from his book "Rotary Engine" 1981

  1.3     REQUIREMENTS FOR A PRACTICAL ROTARY ENGINE
          Although various types of rotary engines have been
  developed to date, there are few that do not qualify as internal
  combustion engines or do not qualify as a practical engine even
  if they satisfy the qualifications of an internal combustion
  engine.
          The requirements for a rotary engine to be qualified
  as a practical internal combustion engine can be summed up in
  the following five items. The practicality of various ideas on
  rotary engines can be judged by evaluating them by these
  criteria:

  (1) Every moving part, including the timing mechanism, should
  make a rotating motion. A mechanism having a reciprocating
  inertia will increase mechanical noise and vibration, and will
  work against high speed and high revolution.  [In addition
  mechanisms that reciprocate generate reversing loads. Reversing
  loads lead to reversing stresses. Reversing stresses lead to
  metal fatigue and limited life. The Wankel rotary engine has no
  reversing stresses therefor the life of the major parts such as the
  eccentric shaft and rotor are unlimited unlike, crankshafts, connecting
  rods, pistons and poppet valves. Paul Lamar]  Accordingly, structures
  that require intake and exhaust valves and mechanisms using the rotors
  oscillatory motion are not desirable.

  (2)     Gas seals or the working chamber should be three
  dimensionally reliable.  The gas seal mechanism of a rotary
  engine should be constituted by connecting the individual seals
  three dimensionally. Among the many ideas we come across are
  those that don't show such three dimensional thoughts.

  (3)     Appropriate gas exchange of intake and exhaust should
  take place. Together with having a mechanism that can correctly
  open and close the ports, sufficient time for intake and exhaust
  should be provided especially for high speed and high
  revolution.  Among the ideas on rotary engines, there are some
  that ignore this point.

  (4)     Every component part should have the strength to endure
  high speed and high pressure.  As the component parts are
  exposed to high pressure, high sliding velocity and high heat
  load, every part should have sufficient allowance in size and in
  shape.

  (5)     Sufficient cooling and lubrication should be provided.
  In order to qualify as an internal combustion engine, although
  this is related to above (4), durability against high heat load,
  high sliding velocity, etc. are required. Therefore, the
  structure should be simple, and the ideas on rotor cooling,
  lubrication of seal parts, and oil seal structure should be
  those that are given adequate thought.
          Also, it is desirable for a practical rotary engine to
  have a simple and compact structure. When we evaluate the
  various type's of rotary engines devised to date in view of the
  above mentioned requirements, the NSU Wankel type rotary engine
  is the engine that best satisfies the above mentioned
  requirements.

------------------------------------------

Indeed, nothing new under the sun :
http://www.dself.dsl.pipex.com/MUSEUM/POWER/unusualICeng/cat&mouse/cat&mouse.htm

For a large overview see :
http://www.dself.dsl.pipex.com/MUSEUM/POWER/unusualICeng/unusualICeng.htm

Randolph Toom
Managing Director
heat2power

Paul,

Yes the engine is based on an old idea but in fairness to the designer it
is not a scissor as it doesn't oscillate. It is probably closer to a
cat and mouse based design but instead of using wedges the inventor
created a tubular pump chamber where circular curved pistons pucks are
mounted on posts, alternatively on two parallel discs.  The discs of
course are surfaced to conform to the tubular combustion chamber and
together, present several sliding faces to have to seal.  These sliding
faces are not as difficult to seal as one would imagine at a constant
temperature but if used for an engine the design would have accommodate
thermal expansion. Probably why it has only run on air to date.  Perhaps
hot air:)

   I can't comment on the snowball chance in hell remark because I can
remember in my youth someone saying the exact same thing about the
Wankel engine.  NASA has awarded worse and dropped better ideas.

Doug in Japan


Not a rotary engine

 Looks like the Bradshaw Omega engine: 1955.
http://www.dself.dsl.pipex.com/MUSEUM/POWER/unusualICeng/toroidalIC/toroidalIC.htm

The Bradshaw engine had a single toroidal cylinder, containing
four double-ended curved pistons. The pistons reciprocated in
pairs, while the cylinder rotated around them, carrying around
the spark plug and inlet/exhaust ports.

The cylinder was rotated by the central shaft while
the cranks that reciprocated the pistons were driven
by the output shaft, running at half the cylinder speed.



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