DYNA JOURNAL ENGINEERING

See in this section https://www.revistadyna.com/noticias-de-ingenieria/mazda-retorna-con-motor-wankel-si-es-que-alguna-vez-se-ha-ido. Despite the multiple and periodic appearances of this technology, the reality is that it has never achieved new and/or extensive practical applications.
On this occasion, LiquidPiston announces its XTS-210 prototype. A multi-fuel two-stroke rotary engine, i.e. it can work as a diesel, with kerosene and other fuels, with water cooling and with a weight of 19 kg it displaces 210 cm3 and achieves a power of 20 kW and 29.4 Nm of torque at 6,500 rpm. This makes it virtually equivalent to a diesel engine five times the size and four times the weight and with only two primary moving parts, the rotor and its shaft.
The manufacturers claim that the historic Wankel engine had a triangular rotor inside a "peanut" shaped housing and that their new design is the opposite, a "peanut" shaped rotor in a tri-lobed housing. The combustion chambers were long and narrow, but now have more capacity, which allows high compression, and the fuel can be injected directly, allowing a diesel engine to run.
The problems that the old rotary engines had with lubrication, which reduced their durability and increased emissions, have also been solved, leaving the seals (the equivalent of piston rings) stationary, which in the Wankel were mobile. LiquidPiston has been developing prototypes for almost 20 years and has tested them in small planes and go-karts, between 40 and 70 HP, running on diesel, gasoline, propane, jet kerosene and hydrogen.
However, the commercialization of the XTS-210 engine (20 kW) will be directed especially to the military field in applications such as portable generators and motorization of conventional UAVs (unmanned aerial vehicles). Hybrid VTOL (Vertical Take-Off and Landing) devices are not ruled out either, with more powerful models.