US2707373A - Liquid fuels turbine and method of operating it - Google Patents

Description

y 1955 E. A. MAYNOR 2,707,373

LIQUID FUELS TURBINE AND METHOD OF OPERATING IT Filed May 20, 1948 IN VENTOR. 63/26 (271762 720 5&9 rvww, I V IA W United States Patent 0 LIQUID FUELS TURBINE AND METHOD OF OPERATING IT Eugene A. Maynor, Chicago, Ill., assignor to Maynor Research Foundation, Inc., Chicago, Ill., :1 corporation of Illinois Application May 20, 1948, Serial No. 28,208

4 Claims. (Cl. 60-39.02)

My invention relates, generally, to liquid fuels turbines and it has particular relation to their method of operation and details of construction.

Liquid fuels turbines differ radically from what are generally known in the art as constant pressure or airgas turbines. The latter require a source of air and oxygen from outside the engine itself. This air must be compressed before entering the engine. I provide, on the other hand, a closed combustion chamber which does not employ an outside source of compressed air and, consequently, has no openings in the chamber to permit the entrance of such air. In accordance with my invention, complete reliance is placed upon the particular fuels and their ratio, properties and functions, to produce the required power.

In the art of rockets, liquid fuel and oxidizers are used to provide the propulsion force to propel the rocket. The use of these fuels and oxidizers to drive a turbine has been impeded by the fact that certain ditficulties in the operation of such turbines appear to be insurmountable.

There are three main difiiculties in the operation and construction of liquid fuels turbines which, heretofore, have been considered to be insurmountable The present invention provides a complete and adequate solution to each of these difficulties. By the term liquid fuels turbine as used herein, I mean a turbine which utilizes, by combining under conditions of combustion, a fuel and an oxidizer, in non-gaseous form, such as, for example, a liquid fuel and a liquid oxidizer.

One of the problems that has been encountered in the operation of liquid fuels turbines is the carbonization of the turbine wheel. It has been found that the blades of the turbine wheel have a deposit of carbon thereon which changes their contours and finally causes it to become completely clogged up.

A second difficulty which has been encountered is the erosion of the blades of the turbine wheel which results from the application thereto of excessive temperature. Heretofore it has not been found possible to generate the required gas jet for impinging on the blades of the turbine wheel to rotate it without at the same time employing such a high temperature that erosion of the blade surfaces results from the flow of the gas jet thereover.

The third problem which has been encountered is the explosion of liquids accumulating at the bottom of the combustion chamber. There have been several instances where these liquids, which have collected at the bottom of the combustion chamber, have caused severe explosions of sufficient intensity not only to destroy the liquid fuels turbine but also to injure and kill personnel operating it.

Accordingly, among the objects of my invention are: To operate a liquid fuels turbine in such manner that there is no carbonization of the turbine wheel or no deposit of carbon on its blades; to prevent erosion of the surfaces of the combustion chamber, jet orifices, and blades of the turbine wheel resulting from operation at 2,707,373 Patented May 3, 1955 ICC excessive temperatures; and to prevent the accumulation of liquids at the bottom of the combustion chamber where they are likely to explode and destroy the apparatus as well as to cause injury to personnel in the vicinity.

There have been efforts to construct a liquid fuels turbine which employed the full admission theory. Such a structure contemplates the building up of pressure in chamber and the separate release of all of that pressure to the blades of the turbine wheel. Such a structure requires the presence of numerous valves, timing devices, etc. In accordance with my invention, which may be considered a chemical reaction turbine employing partial admission, 1 so construct and dimension my combustion chamber and gas discharge nozzles as to permit the continuous build-up of pressure in the chamber while simultaneously permitting sufiicient pressure to be exerted through the nozzles to drive the turbine. I thus escape the requirement for numerous injection and discharge valves, timing devices, etc. Moreover, the full admission theory required a scavenging operation, which is unnecessary in my invention.

Other objects of my invention will, in part, be obvious and in part appear hereinafter.

My invention is disclosed, in part, in the embodiment thereof shown in the accompanying drawing, and it comprises the features of construction, combination of elements, arrangement of parts, and method steps which will be exemplified in the construction and mode of operation hereinafter set forth and the scope of the application of which will be indicated in the appended claims.

For a more complete understanding of the nature and scope of my invention reference may be had to the following detailed description, taken together with the accompanying drawing, in which:

Figure l is a view, partly in side elevation and partly in section, illustrating how a chemical reaction turbine can be constructed in accordance with my invention; and

Figure 2 is a detail sectional view, at an enlarged scale, taken along the line 2-2 of Figure 1.

Referring now particularly to Figure l of the drawing, it will be observed that the reference character 8 designates, generally, a load device, such as an electric generator, having a shaft 9 which supports at one end a turbine Wheel that is indicated, generally, at 10, which normally must be operated at constant shaft R. P. M. (revolutions per minute) but with a fluctuating load. The turbine wheel 10 has blades 11 around its periphery which maybe forty-two in number and which have generally straight entrance and intermediate portions and which have curved discharge end portions against which the jet reacts to drive the turbine wheel 10 in. the manner readily understood. The turbine wheel is contained within the housing 15 at the opposite side of the gas director 13 from the combustion chamber 14.

The gas jet for driving the turbine wheel 10 is directed against the blades 11 through nozzles or orifices 12 which are located in the periphery of a gas blast director 13 that is positioned near the discharge end of a combustion chamber 14 in a housing that is indicated, generally, at 15. As shown more clearly in Figure 2 of the drawing, four nozzles 12 are provided in the director 13 which may be formed of stainless steel or other heat resistant material and in the particular embodiment of the invention which has been constructed has a diameter of four inches. In this construction the nozzles 12 are one-eighth inch wide and three-fourths inch deep. The director 13 is positioned in the outlet end of the combustion chamber 14 so that one of the nozzles 12 is at the bottom as shown. The purpose of this will be set forth presently. It will be understood that the jet, which is generated within the combustion chamber 14, expands outwardly through the 3 nozzles 12 and impinges on the curved portions of the turbine blades 11 to cause the turbine wheel lti'to rotate and drive the electric generator 8 or other load device which may be connected to the turbine wheel 10 as will be understood readily.

The housing 15 may comprise an inner shell 16 and an outer shell 17 of stainless steel having a layer 18'of carbon therebetween or a jacket for regenerative purposes. It will be understood that the carbon layer 18 may be removed and one of the fuels may be pumped between the inner and outer shells 16 and 17 to provide a coolant for the combustion chamber wall. These materials and this construction are employed because of the relatively high temperature existing in the combustion chamber. 14 as a result of the burning of the products therein employed to generate the necessary jet for driving the tufbine wheel 10.

At the other end of the housing 15 there is provided a fuel injector that is shown, generally, at 21. Since the details of construction of. the fuel injector 21 are set forth at length in my copendingapplication Serial No. 5,633 filed January 31, 1948, now Patent No. 2,575,824, and assigned to the assignee of this application, a further description thereof will not be given herein. The fuel may be injected in a constant stream or in continuous, extremely rapid injections.

The fuel injector 21 has fluid inlet conduits 22 and 23 connected thereto for supplying fluids which, when intermixed properly, support combustion in the chamber 14. Shut off valves 24 and 25 may be provided in the conduits 22 and 23. They are shown in the closed position and are arranged to be opened simultaneously by a spring driven drum 26 which is restrained by a pawl 27. When the pawl 27 is released, the drum 26 rotates to open the valves 24 and 25. The fuels are fed from filled tanks 28 and 29 under pressure which may be created in any standard manner.

It will be observed that the conduits 22 and 23 extend into fluid tanks 28 and 29, respectively. The tank 28 may contain a fuel such as aniline, ammonia, furfuryl alcohol and. nitrobenzene. such as nitric acid, picric acid, hydrogen peroxide, liquid oxygen or other oxidizers. Of these fuels and oxidizers respectively, aniline and furfuryl alcohol, on the one hand, and nitric acid, picric acid, and hydrogen peroxide,

on the other hand, are, in combination, spontaneously combustible. The other fuels and oxidizers listed, as well as some other suitable fuels and oxidizers not mentioned herein, require separate ignition; and, in the use of such fuels and oxidizers, any suitable conventional ignition system could. be used.

Referring now to the difficulties enumerated hereinbefore which have been incident to the operation of chemical reaction gas turbines and particularly to the carbonization of the blades 11 of the turbine wheel 10, I have found that this is the result of imperfect combustion. Previously it has been considered to be desirable to employ suchamounts of oxidizer and fuel in the ratio which provides theoretically perfect or stoichiometric combustion. I have found that when this is done a certain amount of carbon residues is left which is deposited on theblades 11 of the turbine wheel 10. This carbon deposit reduces theetficiency of the turbine wheel10-and finally completely clogs up the spaces between the blades 11. when this occurs it has been necessary to dismantle the turbine in order to clean the blades 11 or to replace the turbine wheel 10 with a new one.

I overcome this difficulty by using an excess of oxidizer over that which is required to provide theoretically perfect combustion. Inthe past it has been the practice to employ a ratio of three parts of oxidizer to one part of fuel, the ratio being by weight. Specifically, this .ratio of three to one has been employed where the oxidizer has been nitric acidand the fuel has been aniline. When such a ratio of oxidizer to fuel is employed, the carbonization and erosion of the turbine wheel 10 and nozzles 12 re- The tank 28 may contain an oxidizer In the past sult in the manner described. In many types of engines in which this problem arises in varying degrees, attempts have been made to provide devices for the removal of carbon, such as additional compressed air or a coolant contained within turbine blades, etc. In accordance with my invention I prevent the carbonization of the elements of my device from ever occurring and thus escape the need for devices designed to remove such defects after they occur.

As indicated, I have found that if an excess of oxidizer is employed in the proper ratio the carbon which otherwise would have been deposited on the blades 11 of the turbine wheel 10 unites with oxygen to form carbon monoxide or other gases which flow with the gas jet over the blades 11 of the turbine wheel 19 and are exhausted to the atmosphere. The particular ratio of oxidizer to fuel is important. Where the oxidizer is nitric acid and the fuel is aniline I have found that the maximum ratio should be of the order of five to one for initial ignition. Using this ratio of nitric acid to aniline I have found that the excess carbon, otherwise deposited as a result of theoretically complete combustion, unites with the excess nitric acid as described and flows as a gas to the atmosphere.

Another important result of using this oxidizer to fuel ratio is that the excess acid is vaporized and therefore acts as a coolant which flows through the nozzles 12 in the director 13. This coolant reduces the temperature in the combustion chamber 14 and thus reduces the temperature of the jet which impinges on the blades 11 of the turbine wheel 10. In this manner the second (lllficulty, above referred to, of erosion of the blades of the turbine wheel resulting from excessive temperature is overcome.

The third difficulty which has been encountered. in the construction and operation of chemical reaction gas turbines has been the accumulation of liquids at the bottom of the combustion chamber 14. By positioning the nozzle 12, as shown in the drawing, at the bottom of the combustion chamber 14, it is not possible for any appreciable amount of liquid to accumulate at this point since it is free to flow outwardly through the exhaust end of the combustion chamber 14 in the housing 15. Any liquid which collects at this point is forced outwardly through the nozzle 12 at the bottom of the combustion chamber 14 as a result of the pressure exerted thereon which is generated therein due to the combustion of the products employed for. generating the jet.

I have shown by numerous tests that a chemical reaction gas turbine constructed as described herein and operated in the manner outlined above provides a highly satisfactory performance. Thus there has been provided a complete solution to the several difiiculties which have heretofore confronted those working in this art and the same has been advanced correspondingly.

Since certain changes can be made in the foregoing construction and method of operation and ditferent ernbodiments of the invention can be made Without departing from the spirit and scope thereof, it is intended that all matter shown in the accompanying drawing and described hereinbefore shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. The method of operating a liquid fuels turbine to avoid carbonization and erosion of the turbine blades, combustion chamber and nozzles which. comprises mixing and burning a liquid oxidizer and a liquid hydrocarbon fuel in a combustion chamber using said oxidizer in an amount in excess of that required for theoretically complete combustion and sutficient to cause the carbon res-tiling from combustion to unite with oxygen and form carbon dioxide and to generate a fluid coolant that reduoes the temperature of the jet impinging on the turbine blades, combustion chamber and nozzles below that at which erosion thereof is likely to occur, the-oxidizer being nitric acid and the fuel being aniline, the oxidizer 5 and fuel being employed in a ratio of the order of 5 to 1 by weight.

2. The method of operating a liquid fuels turbine to avoid carbonization and erosion of the turbine blades, combustion chamber and nozzles which comprises mixing and burning a liquid oxidizer and a liquid hydrocarbon fuel in a combustion chamber using said oxidizer in an amount in excess of that required for theoretically complete combustion and sufficient to cause the carbon resulting from combustion to unite with oxygen and form carbon dioxide and to generate a fluid coolant that reduces the temperature of the jet impinging on the turbine blades, combustion chamber and nozzles below that at which erosion thereof is likely to occur, the oxidizer being an acid and the fuel being an aniline, the oxidizer and fuel being employed on the order of 5 to 1 by weight, the ignition thereof being spontaneous.

3. A prime mover comprising, in combination, a hous ing, a combustion chamber in said housing, means in said chamber for supplying and mixing a liquid fuel and a. liquid oxidizer therein, a gas director in the discharge end of said combustion chamber having one or more nozzles therein, and a turbine wheel in said housing having an outside diameter substantially equal to the diameter of said chamber and arranged to be driven by the jet or jets from said nozzle or nozzles, said gas director being positioned between said chamber and said wheel, said chamber being constructed to create pressure in said chamber upon the burning of said fuels, said nozzles being constructed to admit said pressure continuously during said burning of said fuels directly to a portion of said turbine wheel, said housing being formed of an outer shell and a smaller inner shell spaced from said outer shell, said inner shell being surrounded by a layer of carbon disposed between said shells.

4. In a prime mover adapted for comparatively short periods of operation, a tank adapted to contain a supply of liquid oxidizer, a second tank adapted to contain a supply of liquid fuel, fuel conveying means adapted to convey said oxidizer and said fuel from said tanks, cor-- trol valves in said conveyors, a generally tubular housing having an open end and a hemispherical opposite end, said opposite end being sealed against the admission of outside air therethrough, means connected to said conveying means and extending Within said hemispherical housing end and adapted to mix said liquid oxidizer and said liquid fuel within said hemispherical housing end, a gas director in the tubular portion of said housing adjacent said hemispherical end portion, said gas director comprising a plate having an outside diameter substantially equal to the inside diameter of said housing tubular portion and having one or more transverse apertures adjacent the perimeter thereof, said plate constituting a seal for said hemispherical end except for said apertures and forming with said hemispherical end a combustion chamber, said apertures lying in a plane parallel to the axes of said chamber and gas director, a turbine wheel within said tubular portion and having an outside diameter substantially equal to the inside diameter thereof, said turbine wheel being positioned adjacent said gas director and having perimeter blades in alignment with said apertures, and a shaft secured to said turbine wheel and extending beyond said housing References Cited in the file of this patent UNITED STATES PATENTS 850,307 Lloyd et al. Apr. 16, 1907 1,160,145 Davis Nov. 16, 1915 1,197,456 Dinsmore Sept. 5, 1916 1,213,172 Erwin Jan. 23, 1917 1,584,200 Suplee May 11, 1926 1,809,271 Goddard June 9, 1931 1,827,246 Lorenzen Oct. 13, 1931 1,960,810 Gordon May 29, 1934 2,049,446 Holzwarth Aug. 4, 1936 2,283,863 Achterrnau May 19, 1942 2,326,072 Seippel Aug. 3, 1943 2,348,754 Ray May 16, 1944 2,402,418 Kroon June 18, 1946 2,443,841 Sweeney et al. June 22, 1948 2,450,950 Goddard Oct. 12, 1948 2,455,845 Wells Dec. 7, 1948 2,523,009 Goddard Sept. 19, 1950 2,531,761 Zucrow Nov. 28, 1950 OTHER REFERENCES Journal of The American Rocket Society #61, March 1945, pages 4, 5, 6 and 15.

Journal of The American Rocket Society #72, December 1947, pages 6, 7, 8 and 35.

Coast Artillery Journal, pages 30-33, November December 1947.

Coast Artillery Journal, pages 25-29, January-February 1948.

Claims (2)

1. THE METHOD OF OPERATING A LIQUID FUELS TURBINE TO AVOID CARBONIZATION AND EROSION OF THE TURBINE BLADES, COMBUSTION CHAMBER AND NOZZLES WHICH COMPRISES MIXING AND BURNING A LIQUID OXIDIZER AND A LIQUID HYDROCARBON FUEL IN A COMBUSTION CHAMBER USING SAID OXIDIZER IN AN AMOUNT IN EXCESS OF THAT REQUIRED FOR THEORETICALLY COMPLETE COMBUSTION AND SUFFICIENT TO CAUSE THE CARBON RESULTING FROM COMBUSTION TO UNITE WITH OXYGEN AND FORM CARBON DIOXIDE AND TO GENERATE A FLUID COOLANT THAT REDUCES THE TEMPERATURE OF THE JET IMPINGING ON THE TURBINE BLADES, COMBUSTION CHAMBER AND NOZZLES BELOW THAT AT WHICH EROSION THEROF IS LIKELY TO OCCUR, THE OXIDIZER BEING NITRIC ACID AND THE FUEL BEING ANILINE, THE OXIDIZER AND FUEL BEING EMPLOYED IN A RATIO OF THE ORDER OF 5 TO 1 BY WEIGHT.

3. A PRIME MOVER COMPRISING, IN COMBINATION, A HOUSING, A COMBUSTION CHAMBER IN SAID HOUSING, MEANS IN SAID CHAMBER FOR SUPPLYING AND MIXING A LIQUID FUEL AND A LIQUID OXIDIZER THEREIN, A GAS DIRECTOR IN THE DISCHARGE END OF SAID COMBUSTION CHAMBER HAVING ONE OR MORE NOZZLES THEREIN, AND A TURBINE WHEEL IN SAID HOUSING HAVING AN OUTSIDE DIAMETER SUBSTANTIALLY EQUAL TO THE DIAMERER OF SAID CHAMBER AND ARRANGED TO BE DRIVEN BY THE JET OR JETS FROM SAID NOZZLE OR NOZZLES, SAID GAS DIRECTOR BEING POSITIONED BETWEEN SAID CHAMBER AND SAID WHEEL, SAID CHAMBER BEING CONSTRUCTED TO CREATE PRESSURE IN SAID CHAMBER UPON THE BURNING OF SAID FUELS, SAID NOZZLES BEING CONSTRUCTED TO ADMIT SAID PRESSURE CONTINUOUSLY DURING SAID BURNING OF SAID FUEL DIRECTLY TO A PORTION OF SAID TURBIN WHEEL, SAID HOUSING BEING FORMED OF AN OUTER SHELL AND A SMALLER INNER SHELL SPACED FROM SAID OUTER SHELL, SAID INNER SHELL BEING SURROUNDED BY A LAYER OF CARBON DISPOSED BETWEEN SAID SHELLS.

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