Rotary and other non-reciprocating piston engines gather a lot of controversies. Some are fascinated with them while others treat them with a good share of skepticism. No matter whether you hate it or love it, it will be interesting for you to know that a rotary type of engine was recently used for a test on a kart. The results are far from being disappointing.
The novelty has been used in laboratories and closed contests before but now Liquid Piston X-Mini is ready to see the light of the day. This one has some resemblance with well-known Wankel engine. The difference is that X-Mini is based on a rotor of the siamesed-circular type which is placed inside of triangular engine block. While Wankel has a rotor of triangular shape found inside of siamese-circle combustion chamber.
An advantage of this rotor is that it has power density which is way more powerful. It is due to the use of a unique cycle which provides three combustion events per revolution of the rotor. According to Liquid Piston, their engine offers better fuel efficiency. Up to 20% in comparison with a typical combustion engine. It is compact and light with a lower level of noise and vibration. It is said that this idea will be initially used for lawn equipment, however, there are greater plans targeted at electric vehicles.
As for specifications, X-Mini is related to those engines which are gasoline powered and are equipped with 4-pound core placed inside of 6.6” x 6.2” x 5.4” box. It is 30% more compact and light than four-stroke piston units. It consists of two moving parts only showing better power density. The productivity is 3.5 horsepower at 10,000 RPM and 5 horsepower at 15,000 RPM. The overall weight of X-Mini is four pounds. These characteristics are rather impressive compared to typical 30 lbs lawnmower of 5.5 horsepower.
What is more, the engine itself is scalable from 1 to 1000 horsepower. It can be achieved through larger width and diameter of the rotor or through the use of a combination of several rotors. Initially, X-Mini was close to 3 cylinder engine with 4 strokes but with improvements. It ran on diesel in the mode of compression ignition. Today’s X-mini is much more developed. Liquid Pistons plan to integrate their engine into electric vehicles with the ability to cover more than 80% of driving needs. The advantage of battery like this its weight, size as well price providing 30 kW of power with the use of diesel fuel.