Nikolay
SHKOLNIK
Mini-Engine
https://www.youtube.com/watch?time_continue=1&v=0e785YnDmq0
How
It Works : LiquidPiston X Engine
http://www.popularmechanics.com/technology/a21324/engine-startup-liquidpiston-powers-a-go-kart-with-a-4-pound-engine/
Jun 14, 2016
How
a 4-Pound Engine Can Replace a 40-Pound Engine
by Avery
Thompson
Engine
startup LiquidPiston has radically shrunk a go-kart engine,
but it's the military applications that has everyone really
excited.
Connecticut-based startup LiquidPiston announced today that they
have built a small, compact engine that is powerful enough to
drive a go-kart. Their X-mini engine weighs just 4 pounds and
has three moving parts, and yet can produce 3 horsepower, enough
to replace the default 40-pound piston engine that normally
powers the go-kart.
LiquidPiston says that their X-mini is still in a testing phase,
and they hope to get the weight down to 3 pounds and the power
up to 5 hp. (The 40-pound piston engine produces about 6.5 hp.)
In the meantime, their little engine already packs a punch, as
you can see in the video below.
LiquidPiston announced last year that they received a $1 million
DARPA grant to develop their X-mini engine, and it appears that
they've succeeded. The 4-pound, 3-hp engine is small enough to
fit in the palm of your hand, yet it can power everything from
vehicles to generators to drones. The X-mini uses LiquidPiston's
proprietary rotary engine design and thermodynamic cycle which
offer vast improvements over both a traditional Wankel rotary
engine and common piston engines.
LiquidPiston says the X-mini can run on Jet Propellant 8, the
military's fuel of choice, making it an ideal candidate for all
sorts of military applications. For instance, the X-mini is
small and light enough to power a UAV, it can be part of a
generator that can be carried in a backpack, or it can even be
used to power military robotics. According to Alec Shkolnik,
LiquidPiston's co-founder and president, "[DARPA] is kinda
agnostic as to the actual application … they have so many
different applications that need power."
Shkolnik said that the X-mini is still early in testing, and
they have only just built their first working prototype, but
he's hopeful that the engine could see a commercial release
sometime in the next few years. When that happens, the X-mini
could find its way into lawnmowers, emergency generators, and
even small vehicles like mopeds.
http://www.popularmechanics.com/cars/a8174/liquidpistons-hyper-efficient-engine-turning-the-rotary-inside-out-13817971/
Oct 17, 2012
LiquidPiston's
Hyper-Efficient Engine: Turning the Rotary Inside Out
A new
spin on the internal combustion engine by startup
LiquidPiston aims for a leap in efficiency from 20 percent
to 50 percent.
by
Ben
Wojdyla
As automakers augment the reciprocating piston engine with
hybrid systems and improved accessories, independent inventors
are busily working to make huge improvements to the basic
efficiency of the internal combustion engine. Novel designs are
popping up at engineering expos everywhere, and the newest comes
from Bloomfield, Conn.-based LiquidPiston. Its X1 engine is a
simple machine with just three moving parts and thirteen major
components, but it aims to raise thermal efficiency from the 20
percent of a normal gas engine to more than 50 percent, with
drastic reductions in weight and size. How? By wasting much less
energy during the course of an combustion cycle.
Up to 80 percent of the energy in fossil fuels is thrown away
normal engines through the heat and pressure of exhaust, or
dumped to the atmosphere through the radiator. LiquidPiston's
design attempt to capture all of that waste within a tiny
package. "We stretched the performance curves in every direction
to get much higher efficiency," said Alec Shkolnik, President
and CEO of LiquidPiston, "We took the best parts of many
different thermal cycles and combined them." The design is
theoretically capable of 75 percent thermal efficiency, but the
group is targeting 57 percent in real world applications, still
a huge jump.
The basic idea is similar to a Wankel rotary, but turned on its
head. Where the rotor holds the seals in a normal Wankel, the
housing does that job in the X1 engine. This allows significant
reduction in oil consumption over a regular rotary motor. Other
enhancements include direct injection, a high compression ratio
at 18:1, and a dramatic change to the geometry of the combustion
chamber, which maintains a constant volume during ignition. This
change means the air-fuel mixture auto-ignites like a diesel,
and can be burned much longer than normal. The result is a more
complete combustion ending in low emissions and very high
chamber pressures. This high pressure is allowed to act on the
rotor until it reaches nearly atmospheric pressures, so almost
all the available energy is extracted before the exhaust is
physically pushed out. Again, this is different than a normal
internal combustion engine, which releases very energetic,
high-pressure exhaust gas.
Some other slick features: Since the engine is designed to
convert so much more heat energy into mechanical force, less
heat has to be removed from the block, so there's actually no
water cooling system. In cases where the engine is under load
and needs to cool down, it can skip an fuel injection event and
just suck in cool air, which is then heated by the block and
gets exhausted. Another option is to inject water into the
combustion chamber. This has three effects: cooling the engine,
reducing NOx emissions, and converting some of the water to
steam, which increases power.
The compact design of LiquidPiston's lab engine currently tips
the scales at 80 lbs for the 40-hp model. It would weigh less
than 50 lbs in production, the company claims, far less than a
comparable 40-hp diesel that would tip the scale at around 400
lbs. LiquidPiston's current aim is to continue developing the
engine with an eye on the sub-100 hp market — compressors,
hybrid range-extenders, military applications, boat engines —
and license the intellectual property to manufacturing
customers. We love seeing plucky inventors like these to
completely rethinking the gasoline engine.
http://liquidpiston.com/
LiquidPiston
develops advanced rotary engines based on the company’s
patented thermodynamic cycle and engine architecture.
LiquidPiston, Inc.
1292a Blue Hills Avenue
Bloomfield, CT 06002
Phone: (860) 838-2677 info@liquidpiston.com
http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1589586
Paper No.
ICEF2005-1221, pp. 835-845; 11 pages
doi:10.1115/ICEF2005-1221
ASME 2006 Internal Combustion Engine Division Spring Technical
Conference (ICES2006); Aachen, Germany, May 7–10, 2006
High Efficiency Hybrid Cycle Engine
Nikolay
Shkolnik and Alexander C. Shkolnik
Abstract
A “High Efficiency Hybrid Cycle” (HEHC) thermodynamic cycle is
explored. This four-stroke cycle borrows elements from Otto,
Diesel, Atkinson, and Rankine cycles. Air is compressed into an
isolated combustion chamber, allowing for true isochoric
combustion, and extended duration for combustion to proceed
until completion. Combustion products expand into a chamber with
greater volume than intake. We provide details of a compact HEHC
design implementation using rotary pistons and isolated rotating
combustion chambers. Two Pistons simultaneously rotate and
reciprocate and are held in position by two roller bearings. One
Piston performs intake and compression, while the other performs
exhaust and expansion. We predict a reduction of energy losses,
moving part counts, weight and size over conventional engines.
http://papers.sae.org/2008-01-2448/
doi:10.4271/2008-01-2448
Paper #:
2008-01-2448
Rotary High Efficiency Hybrid Cycle Engine
Abstract:
In this paper we discuss a rotary implementation of the High
Efficiency Hybrid Cycle (HEHC) engine. HEHC is a thermodynamic
cycle which borrows elements of Diesel, Otto and Atkinson
cycles, characterized by 1) compression of air only (e.g.
Diesel), 2) constant volume heat addition (e.g. Otto), and 3)
expansion to atmospheric pressure (e.g. Atkinson). The engine
consists of a compressor, an isolated combustion chamber, and an
expander. Both compressor and expander consist of a simple
design with two main parts: a rotor and an oscillating rocker.
Compared to conventional internal combustion engines, in which
all processes happen within the same space but at different
times, in this engine, all processes are occurring
simultaneously but in different chambers, allowing for
independent optimization of each process. The result is an
engine which may offer up to 57% peak efficiency, and above 50%
sustained efficiency across typical driving loads.
http://liquidpiston.com/technology/technical-papers/
http://papers.sae.org/2014-32-0104/
Development
of a Small Rotary SI/CI Combustion Engine
Alexander
Shkolnik, Daniele Littera, Mark Nickerson, and Nikolay
Shkolnik et al., SAE Technical Paper 2014-32-0104, 2014,
doi:10.4271/2014-32-0104.
This paper describes the development of small rotary internal
combustion engines developed to operate on the High Efficiency
Hybrid Cycle (HEHC). The cycle, which combines high compression
ratio (CR), constant-volume (isochoric) combustion, and
overexpansion, has a theoretical efficiency of 75% using
air-standard assumptions and first-law analysis. This innovative
rotary engine architecture shows a potential indicated
efficiency of 60% and brake efficiency of >50%. As this
engine does not have poppet valves and the gas is fully expanded
before the exhaust stroke starts, the engine has potential to be
quiet. Similar to the Wankel rotary engine, the ‘X’ engine has
only two primary moving parts – a shaft and rotor, resulting in
compact size and offering low-vibration operation. Unlike the
Wankel, however, the X engine is uniquely configured to adopt
the HEHC cycle and its associated efficiency and low-noise
benefits. The result is an engine which is compact, lightweight,
low-vibration, quiet, and fuel-efficient.
Two prototype engines are discussed. The first engine is the
larger X1 engine (70hp), which operates on the HEHC with
compression-ignition (CI) of diesel fuel. A second engine, the
XMv3, is a scaled down X engine (70cc / 3HP) which operates with
spark-ignition (SI) of gasoline fuel. Scaling down the engine
presented unique challenges, but many of the important features
of the X engine and HEHC cycle were captured. Preliminary
experimental results including firing analysis are presented for
both engines. Further tuning and optimization is currently
underway to fully exploit the advantages of HEHC with the X
architecture engines.
Methods, devices and systems for power generation through liquid
piston internal combustion engine. The liquid piston internal
combustion engine of the invention, utilizes a novel, synergetic
combination of internal combustion and steam piston engines
within the framework of one and the same system. The engine may
comprise or a plurality of cylinders, each having a liquid
piston. The ICE (Internal Combustion Engine) system comprises
six modules viz PGM (Power Generating Module), ERS (Energy
Recovery System), PCM (Power Conversion Module), HAS (Hydraulic
Shock Absorbers Module), DAC (Data Acquisition & Control
Module) and AEM (Auxiliary Equipment Module).
US9353623
Seal Assembly for a Heat Engine

A
seal assembly includes first and second seal elements
configured to lie adjacent to one another with a lower
portion of each one disposed in a groove and an upper
portion of each one projecting above the groove. The groove
has a length disposed transverse to the direction of
relative motion of a housing and a moving member and is
located in the housing. The seal elements are further
configured so that a contact surface of the upper portion of
each seal element abuts the moving member and configured to
allow independent movement of each seal element relative to
each other in a direction transverse to the groove length.
The seal elements are shaped to define a lubrication channel
therebetween that is configured to allow the passage of a
lubricant therein so as to lubricate motion of the seal
elements relative to each other and relative to the moving
member.
US8863724
Isochoric Heat Addition Engines and Methods

Engines
and methods execute a high efficiency hybrid cycle, which is
implemented in a volume within an engine. The cycle includes
isochoric heat addition and over-expansion of the volume
within the engine, wherein the volume is reduced in a
compression portion of the cycle from a first quantity to a
second quantity, the volume is held substantially constant
at the second quantity during a heat addition portion of the
cycle, and the volume is increased in an expansion portion
of the cycle to a third quantity, the third quantity being
larger than the first quantity.
US2011247583
Internal
Combustion Engine and Components Therefor

A rotary internal combustion engine includes crank-driven gates
to synchronously form chambers for the intake, compression,
combustion, expansion and exhaust of a working medium during a
high-efficiency hybrid engine cycle. A variety of rotor
geometries and sealing apparatuses may work with a rotary
engines in the execution of various engine cycles including, but
not limited to, a high-efficiency hybrid engine cycle.
A rotary engine has a
cycloid rotor and a sealing grid including a face seal that
rotates with the rotor, and including other seals that do not
rotate with the rotor. As the rotor rotates within a housing,
the rotor, housing and seal grid form at least one working
chamber between them, the chamber undergoing a change from
initial volume V1 to V2, which is less than V1, thus compressing
a working medium, and subsequently expanding to volume V3, which
may be larger than V1, such that the chamber volume is a smooth
and continuous function of rotor's rotational angle.
An internal combustion rotary engine includes an air passage
configured to allow cool air to flow through the rotor as the
rotor moves relative to the housing within the engine. Some
embodiments include a removable fuel cartridge.
An internal combustion engine includes in one aspect a source of
a pressurized working medium and an expander. The expander has a
housing and a piston, movably mounted within and with respect to
the housing, to perform one of rotation and reciprocation, each
complete rotation or reciprocation defining at least a part of a
cycle of the engine. The expander also includes a septum,
mounted within the housing and movable with respect to the
housing and the piston so as to define in conjunction therewith,
over first and second angular ranges of the cycle, a working
chamber that is isolated from an intake port and an exhaust
port. Combustion occurs at least over the first angular range of
the cycle to provide heat to the working medium and so as to
increase its pressure. The working chamber over a second angular
range of the cycle expands in volume while the piston receives,
from the working medium as a result of its increased pressure, a
force relative to the housing that causes motion of the piston
relative to the housing.
Engines and methods execute a high efficiency hybrid cycle,
which is implemented in a volume within an engine. The cycle
includes isochoric heat addition and over-expansion of the
volume within the engine, wherein the volume is reduced in a
compression portion of the cycle from a first quantity to a
second quantity, the volume is held substantially constant at
the second quantity during a heat addition portion of the cycle,
and the volume is increased in an expansion portion of the cycle
to a third quantity, the third quantity being larger than the
first quantity.