Concept and Prototype Description of the CRE Engine
One of OTECHOS’ unique technology products is the CRE engine, which is a totally new engine technology.
About the Technology
CRE are initials for ”Centric Reciprocating Engine”, which is an internal combustion engine, where a pair of two rotors moves forth and back related to one another around a common center axis, - further rotating simultaneously around the very same axis, creating chambers performing the phases of suction, compression, expansion and discharge of the exhaust gases.
This movements can be considered to be very alike those of a piston and cylinder in a usual 4-stroke piston engine, and even the respective diagrams are relative comparable. The control of the rotors, as well as the transfer of torque and the synchronizing are secured by a mechanical Control Unit which as well as the Motor Unit is practical vibration free, - from the inertia point of view.
CRE differs from the classes of both rotation engines and piston engines, and is in no way “some type of a new Wankel engine”. Compared to those, the CRE represents a quite new use of geometry far from the Wankel which is tied up in its epitrochoide eccentric geometry, causing its sealing problem, high oil consumption and low thermal efficiency. And CRE do not have the piston engines relatively complicated mechanical construction. This provides:
• An engine that have two active parts only in the engine combustion compartment, corresponding to an eight cylinders 4-stroke piston engine
• No mechanical valves, with two ports only for intake and exhaust gas exchange, - one inlet and one exhaust pipe.
• Ignition provided by a single spark plug or as on the prototype; two plugs in toggling parallel. Further using a single coil (in the prototype also two), and no distributor, - all full electronic controlled. By diesel process one single injection nozzle would be used.
• Very small footprint and extremely low weight.
• A relation between the surfaces in the combustion chamber versus cycled volume that is lower than that of a piston engine, points clearly to lower thermal loss and a higher efficiency. Added to less mechanical losses, reduced fuel consumption in the order of 20 % is calculated compared to a modern car engine.
• Interface with non touching dynamic sealing between the rotors provides an engine free for lubricating oil consumption, and also locks up for use of gases that is known to being cracking oil and oil film. HC emissions would become zero.
• CRE can utilize turbo charging on likely conditions as piston engines. Additionally, it also can achieve benefits of not having the piston engines disadvantages regarding simultaneously opening of the inlet and exhaust valves.
The Prototype(CRE X1) is built as an approx. 200 HP suction engine with a respired volume of 1.15 liter, corresponding to 2.3 liter stroke volume of an 8 cylinders piston engine. Typical it has a circular shape with a diameter of 320 mm and a length of 570 mm, including the coupling to the brake in the test bench. The engine is built ”solid state”, having a coherent body containing the Motor Unit(A) and the Control Unit(B), as shown in the angle mixed section view left. The prototype is rather well proportioned as a result of the parts being machined out of solid blocks, where no special respect to the weight of stationary parts has been taken by its whole design. Still the weight is approx. 68 kilo, ex. the attached equipment.
The CRE Engine can in addition to be used individually also be used together with OTECHOS’ unique technology, the CRC compressor and the CRP pump. The CR technology is patented.
OTECHOS has as of November 2013 issued a program for the development of a new type compressor for air and gases. The main objectives for this new machine, which is based on several patent pending principles, are:
• Less energy consumption, up to 15 - 20% reduction compared with conventionally screw- and piston based machines
• Oil free compression process
• Vibration free, and low noise operation
• Simple construction, - involving very few moving parts
• Low weight and small footprint space
• Being well suited as a gas/steam expansion machine
CRC takes its main advantages in the compression process by no mechanical touching parts in its process chambers, as well as there are no mechanical valves incorporated. This means that there are no need for lubrication, - and also that water injection during the compressing can be used.
Water injection, cooling simultaneously with compression reduces the energy consumption considerably and also performs a sealing effect between the parts, - forming the chambers for suction and discharge.