Tesla-Turbine

A Tesla turbine ( also disc rotor turbine ) is a bladeless turbine, which was invented by Nikola Tesla and on October 21, 1909 patented by him.

It also finds application as a pump, when it is driven.

It consists essentially of a plurality of flat circular discs. These are mounted at a defined spacing on a shaft centrally. Through slots of the fluid stream is introduced tangentially and can speed up the outer rim of the disc close to its own speed flows. The housing of the Tesla turbine is designed so that the flow of fluid can escape only through the outlet located near the axis of rotation. As a result, the decelerated from the edge of rotor disk current of nachfließendem fluid is deflected on a spiral-shaped inner sheet and there is also still can provide acceleration working on the discs, as it runs at a lower peripheral speed there.

A Tesla turbine is based on two principal effects and fluid properties, namely, the adhesion and the viscosity of the fluid. By the adhesion between the fluid and the turbine discs so much energy is discharged from the fluid to the discs, that the rotor is smoothly driven while the fluid delivering energy and inward direction of the outlet flows; after the energy transfer, the fluid flows axially through the opening from the inside to the outside.

The torque is at a standstill at the largest and linearly decreases with the rotational speed until it is at the idle speed to zero. This is also the reason why the highest power at half the fluid velocity (half the idle speed ) is reached.

The work machine Tesla was said to have from 95% to 98% and more pumping efficiencies. However, these data are based more on the legends about Nikola Tesla, than on physical conditions. Systematic studies of Warren Rice of Arizona State University attested an expected efficiency in the range of 40-60%, with an upper limit at 65 %. Practically does not reach the Tesla turbine efficiency today axial turbines.

The advantages of the Tesla turbine is a simple structure, large vibration poverty through lack of imbalances - only when the rotors are as well balanced as bladed turbine, the machine is vibration free - and high cycle resistance ( tolerance to load and temperature changes).

The Tesla turbine did not come in the industrial framework still on the prototype addition, since it reached such a high speed that the material of the discs was expanding in technically unbeherrschbarem extent.