Date: Thu, 05 Mar 1998 22:18:24 -0500 To: GURPSnet-Files@io.com From: Tracy Ratcliff Subject: tesla-engine.txt ---------------------------------------------------------------- Tesla Bladeless Turbines copyright 1998 Tracy Ratcliff (tratclif@mail.bright.net) Nikola Tesla, in his pursuit of more powerful electrical effects, also turned his mind to the generation of electricity. He spent years attempting to perfect his bladeless turbine. Tesla claimed that the bladeless turbine would have a very high power-to-weight ratio, and, since the rotor was built up from simple metal stampings instead of individually machined blades, much cheaper. The bladeless turbine has a rotor made of stack of closely spaced thin metal disks with perforations near the shaft. Steam enters tangent to the outside of the disks, spirals down towards the center and is exhausted out the perforations. The steam turns the rotor by "adhesion" (a modern physicist would call it boundary layer effects). The same principle could be used in a gas turbine. The thickness of the rotor is typically a quarter of the diameter, with smaller diameter cylinders on either side supporting the shaft. Proof-of-concept bladeless turbines are easy to build, but developing an engine that is reliable and as efficient as Tesla claimed has been vexing. Rotors deform or crack under centrifugal effects, and blade spacing is finicky. Bladeless turbines can appear in hard SF settings as flavor — use the stats for the appropriate steam or gas turbines. For more cinematic settings where Tesla's promises were made real (see Alternate Earth's "Gernsback" world) use the following stats. Cinematic Tesla engines come in steam turbine, gas turbine and high-performance (HP) gas turbine versions. TL Type Weight if 5W- 5kW+ Cost Fuel used 6 bladeless steam turbine 75*kW (15*kW)+300 $0.5 0.04C/0.06D 6 bladeless gas turbine 10*kW (2*kW)+40 $7.5 0.07M 6 HP bladeless gas turbine 6*kW (1*kW)+30 $20 0.08J 7+ bladeless steam turbine 50*kW (10*kW)+200 $1 0.02C/0.05D 7 bladeless gas turbine 6*kW (1*kW)+30 $10 0.06M 7 HP bladeless gas turbine 3*kW (0.75*kW)+11 $25 0.07J 8+ bladeless gas turbine 3*kW (0.75)*kW+11 $15 0.055M 8+ HP bladeless gas turbine 2.5*kW (0.5*kW)+10 $40 0.06J Location: Bladeless steam turbines must go in the body. Bladeless gas turbines can go in the body, wings, or pods. Weight: Multiply output by the factor on the table above to get weight. Volume: Divide weight by 50 to find volume in cf Cost: This is the cost per pound of the power plant. Fuel Usage: This is the fuel consumption in gallons per hour (gph) of fuel per kW of output. The letter next to consumption indicates the fuel type: C (coal), D (Diesel), or M (Multi-fuel, using gasoline, diesel, alcohol, aviation gas or jet fuel. A multi-fuel engine will need 1.2 times as much fuel if burning alcohol). Closed-Cycle Operation: A bladeless gas turbine can be designed as closed-cycle engines that operate in the absence of oxygen. Add 50% to the weight, volume and cost of the engine. Add an additional fuel consumption of 2.35 gph of oxygen (LOX) per gph of other fuel consumed. Bladeless Turbine Jets The principle of the Tesla Bladeless Turbine power plant can be reversed and used as a pump, with intake air drawn in along the shaft and propelled out between the spinning rotor disks. In our version of reality, this has only been demonstrated for liquids, and never for vehicle propulsion. In a cinematic Tesla-phile setting, the following air-based jets may be possible. Low-thrust bladeless turbine/jet combos are lighter than equivalent turbojets or turbofans, and always more fuel- efficient. TL Type Motive Weight if Thrust 5W- 5kW+ 6 bladeless turbine jet 3 4*kW (0.4*kW)+18 7 bladeless turbine jet 3.5 3.9*kW (0.3*kW)+18 8+ bladeless turbine jet 4 3.9*kW (0.3*kW)+18 Motive Thrust: Multiply power input by this factor to get motive thrust. Location: Bladeless turbine jets can be located in the main body, pods or wings. Weight: Multiply power input by this factor to get weight. Volume: Divide the weight by 50 to get volume in cf. Cost: $15 per pound of thrust at TL6, $20 at TL7, $25 at TL8 Power Requirements: This is the motive power input.