Digital Tbucket Tank (DTT)

A new aircraft engine?

It's called the Fluidic Propulsive System. (FPS), means the "fluid propulsion system", or perhaps rather the "fluid-based propulsion system", or actually "fluid physics". In fact, it is not a liquid, but a gas, quite simply air, which from a physical point of view can also be viewed as a very low-viscosity liquid.

Andrei Evulet from Romania, who has 15 years of experience at GE Aviation, has been building prototypes of these engines for some time. He was responsible for the technology that is part of the world's largest jet engine, the GE9X, which is working on the Boeing 777X. Together with his school friend Denis Dancanet, he founded Jetoptera a few years ago. They were guided by the idea of ​​creating a new propulsion system that would be ideal for VTOL's vertical take-off flights and that would enable both large unmanned drones and flying cars to be used.

As the founders emphasize, Jetoptera is a company that deals with propulsion systems. The prototype aircraft the company builds are not an end in themselves, and Jetoptera has no intention of devoting itself to building flying machines. It is used to demonstrate this technology. To explain what they are aiming for in air transport, the company's representatives start building helicopters. They are popular flying machines, but they were never intended to be an ordinary means of transportation, a flying taxi. They have large rotors that take up large areas during spinning.

It is a bit dangerous to approach these machines. In addition, they are limited in their maneuverability, noisy, expensive and difficult to control. In a word, it is not an ideal means of flight, although of course it has many advantages compared to the demanding runways of aircraft.

Turns without turbines and propellers

The company's drives use the so-called Coandă effect, ie the phenomenon that a flowing liquid (or a gas if we consider it a very low viscosity liquid) "sticks" to the closest surface and remains "stuck" despite its changing curvature. Its discoverer is considered to be Henri Coandă, a Romanian aerospace engineer and designer who lived between 1886 and 1972. The correspondence between the origins and the founders of Jetopter is probably no coincidence.
It was discovered during research on the world's first jet. Coandă built a wooden airplane with a jet drive in the form of a piston engine that drives a compressor behind which there is a combustion chamber. The exhaust gases from the engine were burned in this chamber. This engine generated a thrust of 1910 N in 2160.

The effect is that a free flowing jet accelerates the stationary liquid particles in the immediate vicinity and thus forms a low pressure "protective shield" around them. If a smooth surface is applied to the jet at this point, the jet is deflected towards the surface and "pressed" against it by the ambient pressure. If the aircraft is not curved too much, under certain conditions the jet can stick to it even after moving around the curved surface, that is, make a full turn. The forces that force a change in the direction of flow also force an identical but opposite rotation, a force on the surface on which the liquid / gas flows. The resulting forces can be used to generate a lift force.

This idea was tried in the 1960s and 1970s when NASA and the US military were working on supersonic jet aircraft. It was eventually replaced by a jet harrier developed in the UK. It was not supersonic and does not use the Coandă effect, but it is a vertical take off and landing jet and works well enough for its purpose.
The Coandă effect is used in Dyson ventilators, among others, although the first patent in this area was granted to Toshiba in 1981. In this type of device, gas is blown into the rim, so that the Coanda effect adheres to the inside of the rim and "sucks" the standing air out of the space inside the ring. In this way, the amount of moving air is many times greater than with a classic fan, which improves the efficiency.

Something between an airplane and a helicopter with no flaws in either version

The designs of the jetopter drives) work a little like the Dyson fans. The manufacturer specifies a thrust / weight ratio of 5 for the most powerful model. For comparison: the ratio for conventional engines used in modern airliners is 5,0 for the Boeing 737-800 and 5,5 for the Airbus A380. Romanian designers were asked to use the Coandă effect to design these engines so that they not only produce useful thrust, but more importantly, that they produce more thrust as they move through the air. They also wanted the same system to be used for both vertical lift and forward flight to save weight and complexity. Their design allows the engines to rotate easily, nothing moves but air, and they are compact in design. The other part of the construction increases the thrust by capturing the air from the environment and accelerating it through the engines. According to the data from the jetopter, the efficiency of this drive is in the position between the helicopter and the aircraft. For example, it is faster than a helicopter, with a top speed of around 320 km per hour when the engines are fully open. The designers claim that one of the variants can reach speeds of up to 740 km / h thanks to the optimal mounting of the engines. The construction is not as effective as a typical helicopter at hovering in place, but it performs much better on this type of ascent compared to the well-known VTOL machines.