Closed Loop, Hybrid, Ceramic Bearings and Higher Efficiency

Once again this Tesla turbine is eagerly awaited. Further improvements have been made after plenty of R&D from the last turbine. The turbine efficiency has been increased by increasing nozzle pressures and added shaped spacers that act like an impulse turbine AFTER the useful energy has be captured using the discs. This may not be that satisfactory to some Tesla purists that don’t think that impulse turbine technology should be mixed with the Tesla turbine but it does increase performance and they can be removed if required and replaced with your own spacers/washers.

There is plenty of interest in using Tesla turbines with organic rankine cycle systems, to enable power generation with waste heat or solar power. A number of major changes have been made to make this turbine useable in a closed-loop system (working fluid is constantly reheated and cooled). In other words no air, gas, steam, water can escape. It is now sealed ready for use in pressured system. It has been tested at 150psi using air.

The turbine still has a standard a 1/4" BSP threaded connector for both the inlet and outlet pipes. A 1/4" BSP to Universal (uni) adapter is provided to allow easy connection to an air compressor (5+ SCFM recommended). The turbine comes with a 3 phase generator and 3 x 20 watt bulbs so that a load can be drawn, this generates 60 watts. The generator can produce up to 150watts leaving plenty of headroom for experimentation. The turbine design and generator mount allows for possibility of changing the generator or connecting to something else. The turbine is supplied on a aluminium base for display and demonstration purposes (connected using two M6 Hex cap screws).

History of Tesla Turbines

A Tesla turbine is a quite unique technology. It was invented and patented by Nikola Tesla on the 21st October 1909 at the United States Patent Office from experiments done in England. The US patent 1061206 was granted on the 6th May 1913, although historical documents suggest that that Tesla first showed a 200 horsepower (about 150kw) 16,000 RPM version on the 10th of July 1906 (on Tesla’s 50th birthday).

From what Tesla wrote in the patent it seems his experiments were mainly done with fluids but had confirmed it works with air as well. Tesla had his own personal requirements for a generator for his laboratory. You have to remember use of electrical power was still in its infancy which Tesla played a critical role developing many of the electrical components we now take for granted. Typically Tesla found his alternative and better way of generating power, using a steam boiler powering a tesla turbine which in turn powered an AC generator.

Unlike conventional turbines, jet engines and most pumps, Tesla’s turbine can be designed to be reversible with no loss in efficiency. Normally compressed air, fluids or steam is applied to the inlet and the turbine spins giving a mechanic rotational output. However, it can also double up as a pump, by rotating the shaft the air/fluid/steam can and be sucked and blown from the inlets / outlets. This makes it unique in being a reversible turbine and a reversible pump. However efficiency increases can be made by tailoring the pump to the medium. In other words an air powered turbine may have some slight design changes compared to water powered turbine.

Sadly unlike the work done with electricity the Tesla turbine never became popular and was simply forgotten about. Only in the last few years has there been new interest. Tesla turbines are also known as cohesion turbines, bladeless turbines, boundary layer turbines and Prandtl layer turbines.

Working with Air, Steam, Water, Vacuum and Hot Gases

This turbine is ideal for experiments with air, steam, water and hot gases. With air or a Vacuum no special precautions need to be undertaken. With hot gases ensure the generator housing (and hence generator) does not over heat; prolonging the generator life. Try to keep the temperatures below 100C. I would suggest trying heat sinks and cooling-jackets around the generator casing. With steam and water mount the turbine so the generator is vertical and facing upwards (at the top). This means if any water does get into the generator compartment it can return back into the main compartment and outlet over time. If this is still a persistent problem I would suggest changing the bearings for ones with rubber seals (bearings 625-2RS) which will provide extra protection to the generator. With steam and water slowly increase the pressures with each experiment and check the generator housing. The turbine has been tested at 150psi with compressed air. If you do use high pressures please understand the risks and take the appropriate safety precautions.

Key points

• NEW closed loop - ideal for organic rankine cycle systems
• Hybrid Turbine - using Tesla technology and impulse turbine technology to improve efficiency
• Ceramic Bearings - faster, more efficient, high temperatures
• Higher Efficiency -Runs from air, a vacuum, steam, gases and even water
• Aluminium casing and disks with stainless steel shaft
• Brass injection nozzle+ free blank nozzle
• Comes with 60 watt of bulbs to demonstrate electricity production
• Generator can produce up to 150watts
• Easy to customise
• 5 disks with a diameter of 71.75mm (2.8inch)
• Disk gap spacing is 1.45mm (can be changed with new spacers)
• Outer casing is 100mm (3.9 inch) diameter by about 120mm long (4.7 inch)
• 1/4 inch BSP thread for inlet and outlet
• tens of thousands of RPM possible

 Download the manual