Pistonless rotary engine

A rotary engine is an engine in which to perform the parts that perform mechanical work, only rotational movements.

This design offers several ways to convert energy into rotary motion. If the energy in the form of hydraulic or pneumatic pressure is available, one can use, for example, vane motors.

If the energy chemically bound available, eg in the form of liquid fuel (gasoline, diesel, alcohol, etc. ), you can run the engine as a heat engine.

This lead the parts that perform mechanical work, as opposed to a periodic reciprocating rotary motion. The energy conversion process can run on different clock sequences. These different clocks ( fill, blow, etc. ) take place during the rotation (s).

• 2.1 rotary engine
• 2.2 rotary engine

Basic Pros and Cons

Benefits

• Simplicity: Potentially fewer moving parts than reciprocating engine in, thus simpler, more robust construction. In contrast to the reciprocating engine in general also eliminates the transmission of power by means of the crankshaft.
• Smoother running: Many rotary engines are fully auswuchtbar, which has much lower vibration than the reciprocating engine result.
• Lower power to weight ratio: Since many rotary engines are to build very compact and with few parts, the power to weight ratio reduced to a fraction of that of reciprocating engines.

Disadvantages

• Problematic seal: rotary engines have to fight depending on the type, to varying degrees with sealing problems. While sealing the combustion chamber of reciprocating engines is relatively easy and reliable to accomplish by means of piston rings (but represents a speed- limiting factor, as piston rings coincide at high speeds and fail ), must be used in rotary engines different sealing systems partially.
• Unfortunately crescent-shaped combustion chamber of the rotary engine compared to hemispherical, formed by the cylinder wall, cylinder head and the piston head combustion chamber of a reciprocating engine. Although this provides an optimal ratio of ( minimal ) surface ( maximum ) volume, but one must also take into account here the enforced displacement volume, cycle time and actually lossy surfaces. Incidentally noted was here that the ideal hemispherical combustion chamber ( a multi-valve arrangement is difficult to implement ) because of its narrowly defined geometric design options and an increased Glühzündungs ​​and ring inclination, caused by the rotation symmetry (caused a focusing), which quickly leads to holes in the piston crown, today only rarely is used.
• Often very specific components must be made ​​due to the design, which increases manufacturing costs. These parts may even complicated to manufacture, thereby reducing the costs and effort required for the production of a rotary engine further.
• Difficult Lubrication: Lubricating oils and greases should not enter certain areas of the engine, so they do not burn and the working process is adversely affected as a rule. This can, however, usually not, or not completely prevent or it's a huge hassle. Coatings, Teflon, ceramic or graphite offer under certain circumstances an alternative, but these are some more expensive than conventional lubrication and expensive to manufacture and maintain.

Construction

Rotary piston engine

All moving parts of a rotary piston engine rotate around a fixed point (usually about their own center of gravity). Although a large number of patents for rotary engines exist, so far none of them proved to be as competitive or practical.

Rotary engine

When rotary engine rotate all the parts that do work on a circular path. Again, there are a plethora of patents that were not realized. The only exception (and therefore the only production-ready rotary engine at all) is the rotary engine. In the interpretation of a circular piston Wankel he represents the kinematic reversal for rotary Wankel dar. With him no longer rotor and rotate envelope figure ( trochoid ), but only the runners. The envelope figure is fixed as housing to the outside world. The slider now rotates not only around its own center of gravity, but so that the focus additionally revolves on a circular path.