Zero Emissions Turbofan [With Aeroderivative Power Generation and Marine Applications]

Abstract

This is an application for a utility patent for a zero emissions turbine, suitable for use in aerospace, power generation, industrial, and marine applications, that runs on the combustion of liquid hydrogen and liquid oxygen and which is cooled by liquid oxygen. It is unique in that its only emissions will be steam, water vapor, pure oxygen, and ice crystals, with no pollutants or greenhouse gases of any kind. It is also unique in that it uses no air intake, no compressor, and simplified shaft and auxiliary drive systems. It has a unique tank and pump system that runs on electric motors and specialized lubricating systems. These turbines can be designed with powerful and reliable operating specifications with greatly reduced fuel consumption and greatly improved power-to-weight ratios.

Claims

1. This is the design of a new type of zero emissions turbine, suitable for use as an aerospace turbine, as an aeroderivative power generation gas turbine, and as a marine turbine, that runs on liquid hydrogen and liquid oxygen fuel and uses a liquid oxygen cooling system, producing an exhaust of steam, water vapor, ice crystals, and pure oxygen.

2. This is a unique gas turbine design in that it does not require any air intake or compressor, unlike every other working gas turbine design in the world today. Instead, it creates the pressure used to turn the turbine solely by burning and gasifying its fuel in the combustor. Unlike modern steam turbines, it does not require a massive independent boiler to create steam pressure. As such, it can use greatly simplified shaft and auxiliary drive designs, and can create much more usable power with much less fuel, at any altitude, at any depth in the ocean, in any kind of weather condition, at any foreseeable temperature, and practically irregardless of bird strikes and interference from other airborne objects.

3. This design uses a unique system of liquid hydrogen and liquid oxygen fuel pumps and tanks driven by electric motors that, in the aerospace turbofan design shown in the drawings, run on 28 volt DC current provided by a generator and APU unit and which employ their own three proprietary pump and lubrication systems and which, in the power generation and marine genset versions, may run on 120/240 volt AC current with similar differentiation between the three separate pump and lubrication systems. It does not use the more or less standard turbopumps that are found on every modern rocket engine that burns this type of fuel. This makes operation and cooling more predictable, more controllable, more reliable, and more stable for long-term continuous, uninterrupted, and often variable rate usage that can last for hours, days, weeks, and months at a time and which, in that way, will tend to be markedly dissimilar from the 30-second one-time full-power blast that is standard operating procedure in most rocket designs of this type today.

Description

DRAWING VIEWS

[0020] The drawings are design development drawings which show the major components but which do not show nuts and bolts, welds, sensors, actuators, engine control units (ECUs), electronic harnesses, buses, and interfaces, most wiring, engine controls and displays, seals, bearing sections, and some of the smaller piping connections. Material types are not shown. In the aerospace version, these materials would be aircraft aluminum alloys, titanium/aluminum alloys, stainless steel alloys, nickel and chromium alloys, modern turbine blade and stage alloys and materials, modern bearing alloys and materials, modern sealing system alloys and materials, and modern fan composites and alloys. In the power generation version, many of the lighter aluminum and titanium elements would be replaced with heavier steel and nickel alloys, and the same can be true in marine versions. Some versions may include modern turbine blade coatings.

[0021] The alternators, generators, independent drives, electric motors, and APUs are designed as standard modern versions, for the most part, as are many of the sensors, actuators, valves, pumps, filters, and fuel lines. The three separate lubrication systems, for the main bearings and shaft, the hydrogen pump, and the oxygen pump, all require their own specialized lubricants. The fuel tanks will be a custom highly-insulated temperature controlled design with multiple pressure relief valves, a cooling system, a boil-off re-liquefaction system, and a tank and fuel line purging system.

[0022] The drawings are a revision of the original set submitted in this application, as requested by the USPTO.

[0023] Drawing 1, labeled FIG. 1 Perspective section, is a cutaway perspective section showing the turbine in its aerospace version, with sections taken through the nacelle, the turbine casing, the combustor, and the fuselage. The 5 turbine stages, the 3 main bearings, the fuel line feeds to the combustor, and the combustor walls with coolant passages can clearly be seen.

[0024] Drawing 2, labeled FIG. 2 Perspective, is a perspective rendering from the left front of the aerospace version showing the fan and the complete nacelle along with a section through the fuselage.

[0025] Drawing 3, labeled FIG. 3 Rear perspective, is a perspective rendering from the right rear of the aerospace version showing a section of the fuselage with the independent drive generator, the hydrogen pump and its electric motor, and the lubrication systems.

[0026] Drawing 4, labeled FIG. 4 Front elevation, is a frontal view of the aerospace version and section through the fuselage that shows the fan, the independent drive generator, the hydrogen pump, the oxygen pump, and the main bearing and shaft lubrication system.

[0027] Drawing 5, labeled FIG. 5 Right elevation, is a section through the fuselage showing the independent drive generator, the hydrogen pump and its electric motor, the oxygen pump and its electric motor, the main bearing and shaft lubrication system, the oxygen pump lubrication system, and the hydrogen pump lubrication system.

[0028] Drawing 6, labeled FIG. 6 Rear elevation, shows the rear of the turbine system and a section through the fuselage showing the main oil cooler, the oxygen pump electric motor, the hydrogen pump electric motor, the oxygen lubrication system, and the hydrogen lubrication system.

[0029] Drawing 7, labeled FIG. 7 Left elevation, shows the left side of the nacelle and front end of the fan.

[0030] Drawing 8, labeled FIG. 8 Liquid oxygen cooling system section A, is a perspective rendering and perspective section of the liquid oxygen cooling system, showing the liquid oxygen pump and its electric motor, the fuel line leading to the combustor feed system, and a cutaway section of the combustor showing the coolant passages running through the inside wall of the combustor, the stators, and the outside wall of the combustor, before sending the liquid oxygen back into the combustor itself.

[0031] Drawing 9, labeled FIG. 9 Liquid oxygen cooling system section B, is the same perspective rendering and perspective section as FIG. 8 but with the addition of lighter lines representing hidden interior spaces and objects that show the insulated double-walled vacuum-jacketed pipe used in the fuel lines and the fuel feeds to the combustor and the liquid oxygen coolant passages completely encircling the main chamber of the combustor.

[0032] Drawing 10, labeled FIG. 10 Aerospace schematic layout, is a schematic perspective rendering and perspective section of the major components of a typical aerospace set-up, including the turbofan, liquid hydrogen wing tanks, liquid oxygen fuselage tanks, and an auxiliary power unit (APU) at the rear.

[0033] Drawing 11, labeled FIG. 11 Power generation schematic layout, is a schematic perspective rendering of the major components of a typical power generation set-up, including the turbine, the generator, the pump, electric motor, and lubrication system housing, the liquid hydrogen tank, the liquid oxygen tank, and an optional APU.

[0034] Drawing 12, labeled FIG. 12 Marine direct drive turbine schematic layout, is a schematic perspective rendering of the major components of a marine direct drive system, including the turbine, the main shaft, the gear, clutch assembly, and optional power take-off housing, the pump, electric motor, and lubrication system housing, the liquid hydrogen storage tank, the liquid oxygen storage tank, and an optional APU.

DESCRIPTION OF THE INVENTION

[0035] This turbine design is unique in its use of fuels, its construction, and its performance. It burns two cryogenic fuels, liquid hydrogen and liquid oxygen, in its combustor to create pressure that spins turbine stages which rotate a central shaft to create power. In that way it is similar to thousands of modern gas turbines, but that is where the similarity ends. This design has no air intake whatsoever, for one thing. In aerospace versions, that means that potential power is limited only by weight and by the lift and drag on the engines, wings, tail, and fuselage, and is not limited by altitude other than by the effect of decreasing air pressure in the fan, giving this design a large edge on modern jet turbofan designs. In marine versions, that means that this design can operate in any kind of weather, at any temperature, and at any depth, if required.

[0036] This design uses no compressor whatsoever, unlike every other working gas turbine design in the world today, relying instead on the gasification and expansion during combustion of its two fuels for power. That is an absolutely massive advantage over any other gas turbine, a real game-changer. It is a bit difficult to predict the exact size of that advantage in numbers prior to tests of actual working models, but based on available figures for the thrust-specific fuel consumption of different types of existing aerospace engines, it may increase the available thrust per pound of fuel by an estimated factor of about ten or so, and that same factor would also apply to turbines used for power generation, marine direct and indirect drive systems, and industrial processing. Modern jet turbofans often require as many as three separate shafts to drive the fan and the compressor along with a large auxiliary drive shaft for everything else. Power generation and marine turbines can also employ multiple shafts. This design requires one shaft for the fan and one auxiliary drive for the independent drive generator. The simplified design saves about half of the weight of the turbine itself by eliminating the extra shafts, extra bearings and seals, and all of the compressor stages. These changes unlock a whole new world of power production and fuel economy for gas turbines, along with a whole new world of potential range for jet aircraft.

[0037] The similarity with rocket engine designs has been noted above. However, in place of turbopumps pressurizing the fuel lines, which have now been standard in rocket design since the days of rocket pioneer Robert Goddard back in the 1920s, this design uses pumps driven by electric motors to create pressure in the lines and the combustor head. The somewhat greater weight of those pumps and the generator is offset by their independent speed controls and their zero to 100 percent speed range, creating a whole new world of fuel pressure control in this design. It means that pre-cooling and start-up procedures should be able to run without a hitch in this model, and it makes long-term continuous running, for hours, days, weeks, and months at often variable rates not only possible but entirely practical. In addition the design employs three separate lubrication pump and filter designs, one each for the main bearings and shaft, the liquid hydrogen pumps, and the liquid oxygen pumps.

[0038] Most rocket designs that burn these two fuels use liquid hydrogen cooling to save weight. This design uses liquid oxygen, a heavier and somewhat less efficient coolant, but one with a much, much wider usable temperature range and an emission, pure gaseous oxygen, that is not a pollutant, unlike rockets which can produce ammonia and methane in their exhausts. The liquid oxygen is pumped at high pressure through coolant passages in the interior wall of the combustor, then through the first stage of turbine stators to the coolant passages in the outside wall prior to entering the combustor and burning with the liquid hydrogen. It is also added through film cooling holes along the outside edges of the combustor head. In addition a fuel cooling system, which adds additional liquid oxygen to the ratio of the liquid hydrogen to liquid oxygen to help control the combustion temperature and length of the flame is also employed. This design is aided by pumps, valves, and lines protected with insulation and vacuum-jacketed construction and piping, and by temperature-controlled fuel tanks featuring exterior insulation, a triple-wall double vacuum-jacketed shell insulated by evacuated porous or multi-layer insulation in between the walls, liquid fuel cryocoolers that use helium to chill the liquid hydrogen and argon or nitrogen to chill the liquid oxygen, a boil-off re-liquefaction cryocooler with phase correction, a gas or vacuum tank and fuel line purging system, and multiple pressure relief valves vented to the exterior on every tank. In this design the fuel enters the pumps and fuel line feeds to the combustor at known, controllable, and constant temperatures and in a known phase and state, regardless of exterior air temperatures, air pressure, and weather. This is an advance over modern cryogenic fuel tank designs, although NASA has been working on some similar designs recently, new LNG tanker ships and some modern helium tanker trucks now employ triple-walled shell construction and can be equipped with cryocoolers and boil-off liquefaction systems, and most large cryogenic fuel tanks have at least one pressure relief valve.

[0039] The end result is a totally emissions-free design, the first workable zero emissions gas turbine in the world. The exhaust is just steam, water vapor, oxygen, and, at high altitudes and cool temperatures, ice crystals. It is a design that has the potential to increase aircraft range and cruising altitude, to increase the power output of marine turbines, and to increase the power output of power generation and industrial combustion turbines in engines of an equivalent size, weight, and fuel consumption.

[0040] This design is becoming increasingly practical as “green” hydrogen and oxygen production plants that use electrolysis to separate water are starting to appear all over the world this year, plants that employ wind energy, solar energy, hydroelectric power, and nuclear energy as their power source; as new and more efficient means of storage and transport of these fuels appear; and as plans to make these fuels available at major airports, rail terminals, marine depots, and power generation facilities are being planned. These are all brand new developments that have taken place in just the past year or two.

[0041] The end result is a totally emissions-free design, the first zero emissions gas turbine in the world. The exhaust is just steam, water vapor, oxygen, and, at high altitudes and cool temperatures, ice crystals.