This is an interesting take on rotary
engines-http://liquidpiston.com/technology/engine-benefits/

Brian Trubee

Very clever. Felix Wankel investigated this basic geometry and
rejected it, It has some serious rotor cooling problems.  Since the
rotor contains the exhaust on one side and the intake charge on the
other the VE will be strongly affected as the rotor warms up to
operating temperature. In addition the rotor will be subject to
combustion temperatures on the outside  further adding to the rotor
cooling problems. This will tend to distort the rotor.

Sealing the sides of the rotor will also be a nightmare. The leaning
angle on the apex seals will also be a serious problem. At high
leaning angles the seals tend to jam in the slots due to differential
pressure loads across the seal and the coefficient of friction
between the seal and the slot.

It might work in very small sizes as the distortion of the rotor due
to uneven heating may have less of an effect. A silicon nitride rotor
may help.

The combustion chamber shape has the same surface area to volume
ratio problems as the Wankel.

Paul Lamar

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
dimension-ally reliable.  The gas seal mechanism of a rotary engine
should be constituted by connecting the individual seals three
dimension-ally. 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.

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

    Hi!: nice drawings, I'd say the Liquid Piston engine is almost the same as the one
that Rambler/Renault studied, there are some patents, that can be retrieved
and downloaded for free  in: 'ESPACENET', by searching:  'Rotary Engine', as
 keyword, and: 'Renault', as applicant, and also some magazine reports.
  The main problem I see in this Rambler arrangement is that it looks more
cumbersome than a Wankel RCE, its gravity center placed high, or taking too
much space if left   horizontal, and also it has ordinary valves, reducing the
simplicity advantages the Wankel has. Hope you like it.
   Have a good season, best regards. Salud †
        Jose Gros-Aymerich
            Madrid, Spain


The Rotary Engine News Letter. Powered by Linux. ACRE NL web site.
http://www.rotaryeng.net You Tube http://tinyurl.com/beqqxas
Copyright 1998-2014 All world wide rights reserved.