TESLA TURBINE:
Bladeless centripetal flow turbine patented by Nikola Tesla in 1913.[1] It is referred to as a bladeless turbine. The Tesla turbine is also known as the boundary layer turbine, cohesion-type turbine, and Prandtl layer turbine (after Ludwig Prandtl) because it uses the boundary layer effect and not a fluid impinging upon the blades as in a conventional turbine. Bioengineering researchers have referred to it as a multiple disk centrifugal pump.[2][3] One of Tesla’s desires for implementation of this turbine was for geothermal power.
Tesla wrote, "This turbine is an efficient self-starting prime mover which may be operated as a steam or mixed fluid turbine at will, without changes in construction and is on this account very convenient. This construction permits free expansion and contraction of each plate individually under the varying influence of heat and centrifugal force and possesses a number of other advantages which are of considerable practical importance. A larger active plate area and consequently more power is obtained for a given width, improving efficiency. Warping is virtually eliminated and smaller side clearances may be used, which results in diminished leakage and friction losses. The rotor is better adapted for dynamic balancing and through rubbing friction resists disturbing influences thereby ensuring quieter running. For this reason and also because the discs are not rigidly joined it is protected against damage which might otherwise be caused by vibration or excessive speed. Minor departures from the turbine, as may be dictated by the circumstances in each case, will obviously suggest themselves but if it is carried out on these general lines it will be found highly profitable to the owners of the steam plant while permitting the use of their old installation.
EFFICIENCY:
Tesla's design attempted to sidestep the key drawbacks of the bladed axial turbines, and even the lowest estimates for efficiency still dramatically outperformed the efficiency of axial steam turbines of the day. However, in testing against more modern engines, the Tesla Turbine had expansion efficiencies far below contemporary steam turbines and far below contemporary reciprocating steam engines. It does suffer from other problems such as shear losses and flow restrictions, but this is partially offset by the relatively massive reduction in weight and volume. As time went on, competing Axial turbines became dramatically more efficient and powerful, a second stage of reduction gears was introduced in most cutting edge U.S. naval ships of the 1930s. The improvement in steam technology gave the U.S. Aircraft Carriers a clear advantage in speed over both Allied and enemy aircraft carriers, and so the proven axial steam turbines became the preferred form of propulsion until the 1973 oil embargo took place. The oil crisis drove the majority of new civilian vessels to turn to diesel engines. Axial steam turbines still had not exceeded 50% efficiency by that time, and so civilian ships chose to utilize diesel engines due to their superior efficiency. Some of Tesla turbine's advantages lie in relatively low flow rate applications or when small applications are called for. The disks need to be as thin as possible at the edges in order not to introduce turbulence as the fluid leaves the disks.
Bladeless centripetal flow turbine patented by Nikola Tesla in 1913.[1] It is referred to as a bladeless turbine. The Tesla turbine is also known as the boundary layer turbine, cohesion-type turbine, and Prandtl layer turbine (after Ludwig Prandtl) because it uses the boundary layer effect and not a fluid impinging upon the blades as in a conventional turbine. Bioengineering researchers have referred to it as a multiple disk centrifugal pump.[2][3] One of Tesla’s desires for implementation of this turbine was for geothermal power.
EFFICIENCY:
Tesla's design attempted to sidestep the key drawbacks of the bladed axial turbines, and even the lowest estimates for efficiency still dramatically outperformed the efficiency of axial steam turbines of the day. However, in testing against more modern engines, the Tesla Turbine had expansion efficiencies far below contemporary steam turbines and far below contemporary reciprocating steam engines. It does suffer from other problems such as shear losses and flow restrictions, but this is partially offset by the relatively massive reduction in weight and volume. As time went on, competing Axial turbines became dramatically more efficient and powerful, a second stage of reduction gears was introduced in most cutting edge U.S. naval ships of the 1930s. The improvement in steam technology gave the U.S. Aircraft Carriers a clear advantage in speed over both Allied and enemy aircraft carriers, and so the proven axial steam turbines became the preferred form of propulsion until the 1973 oil embargo took place. The oil crisis drove the majority of new civilian vessels to turn to diesel engines. Axial steam turbines still had not exceeded 50% efficiency by that time, and so civilian ships chose to utilize diesel engines due to their superior efficiency. Some of Tesla turbine's advantages lie in relatively low flow rate applications or when small applications are called for. The disks need to be as thin as possible at the edges in order not to introduce turbulence as the fluid leaves the disks.
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