ADAPTED PROCESS CONCEPT AND PERFORMANCE CONCEPT FOR ENGINES (E.G. ROCKETS), AIR-BREATHING PROPULSION SYSTEMS (E.G. SUBSONIC RAMJETS, RAMJETS, ROCKET RAMJETS), TURBOPUMPS OR NOZZLES (E.G. BELL NOZZLES, AEROSPIKES)

Abstract

Chemical thrusters convert chemical energy predominantly into thermal energy and further into kinetic energy. These conversions are lossy and typically limit the usable thrust to 40-70% of the chemical energy (rockets). The exit velocity is maximized by increasing the temperature. However, temperature cannot be increased at will and can increase losses. Thrusters also have limited controllability under changing external conditions. The options for isochoric or detonative combustion are limited. This concept is intended to increase efficiency and controllability.

Through changes in catalytic loads and electromagnetic dose, combustion is increased and can be selectively regulated. Pressure/temperature are influenced and can be adapted e.g. to the changing external pressure. The achievable thrust increases due to the higher exit velocity. Further advantages exist. The geometry of combustion chambers can be optimized (e.g. smaller, more efficient). The concept is particularly promising for detonation engines or novel supersonic combustors.

Claims

1. A process for ignition or reaction in chemical engines or turbines (e.g. rocket engines, gas turbines or gas turbines for turbopumps), air-breathing engines, comprising: At least one catalytic absorber for electromagnetic waves and at least partial excitation by means of electromagnetic waves, both in combination with so-called process parameters and combustion chamber properties comprising at least one of the following process parameters: Reaction rate, reaction temperature, reaction pressure, flow velocity in the combustion chamber, and additionally having at least one of the following combustion chamber properties: permissible mass flows, cooling, combustion chamber geometry, combustion chamber length, combustion chamber width, combustion chamber cross section, constriction of the nozzle throat, nozzle length, nozzle inclination, the fuel concentration in air-breathing engines, compressor pressure ratio or compressor pressure ratios of several components of the engine.

2. A process according to claim 1, comprising: At least one homogeneous catalyst (e.g., of one or more platinum group metals, element(s) of subgroups IV, V, VI, VII, VIII, I and II) introduced into the combustion chamber.

3. A method according to claim 1 comprising: other metallic additives are introduced into the combustion chamber that are not used as electromagnetic absorbers and are not catalytic.

4. A method according to claim 1 comprising: at least one heterogeneous catalyst (e.g., of one or more platinum group metals, element(s) of the IV, V, VI, VII, VIII, I and II subgroups) is placed in the combustion chamber.

5. A method according to claim 1 comprising: a turbulent combustion is carried out selectively or intermittently or partially.

6. A method according to claim 1 comprising: Pressure surges or pulses and any of the foregoing regulated by at least one of: varying loads of homogeneous catalysts as absorbers, further loads of metallic additives, level of electromagnetic dose rate intensity, pulsing of electromagnetic waves, selective excitation of propellant constituents.

7. A method according to claim 1 comprising: At least one other electromagnetic wave type, such as microwave, magnetic wave, radar wave, x-ray wave.

8. A method according to claim 1 comprising: the temperature gradient is influenced by heat reflection of heterogeneous catalysts (e.g. platinum) in the engine (e.g. internals), or the combustion chamber wall, and the heterogeneous catalysts are kept free from aging or fouling by additionally introduced loads of homogeneous catalysts.

9. A method according to claim 1 comprising: at least temporarily reacting by means of isochoric or detonative changes of state at least a portion of the propellant.

10. A method according to claim 1 comprising: a combustion chamber pressure which is specifically directed to the best possible compression efficiency of individual assemblies (e.g. the inlet, or the nozzle), or the overall engine.

11. A method according to claim 1 comprising: stabilizing or adjusting at least one process parameter, such as the temperature or pressure in the combustion chamber, by means of catalytic absorbers or electromagnetic excitation during the combustion termination phase of the engine or when the fuel mass flow of the engine is changed.

12. A method according to claim 1 comprising: where applicable, rendering existing fuel residues in tanks or lines useful to the engine by at least one of: catalytic absorbers, or assisting the reaction by electromagnetic waves (e.g., microwaves).

13. A method according to claim 1 comprising: by the additions of catalytic absorbers or other metallic additives in which latent heat is used by at least one phase change for at least one adjustment of the so-called process parameters or the permissible combustion chamber properties: Temperature equalization, temporary cooling of at least one engine area such as the constriction of the nozzle, performing volume change work, pressure lowering during cooling.

Description

BRIEF DESCRIPTION OF THE DRAWING FIG.S

[0087] FIG. 1: Energy diagram of an engine—state of the art.

[0088] In this FIG. a simplified energy scheme is shown.

[0089] FIG. 2: Energy diagram of an engine—performance concept.

[0090] In this FIG. another simplified energy scheme is shown.

[0091] FIG. 3: Energy flow—adaptation by process concept.

[0092] In this FIG. a Sankey diagram is shown.

[0093] FIG. 4: Process control.

[0094] In this FIG. schematics are linked together.

[0095] FIG. 5: Schematic—laminar combustion.

[0096] In this FIG. a schematic for laminar combustion is shown.

[0097] FIG. 6: Combustion chamber for rocket engines according to [1].

[0098] In this FIG. various basic shapes for combustion chambers are shown.

[0099] FIG. 7: Thermal insulation by reflection.

[0100] The FIG represents the scheme for heat reflection by means of catalytic coating.

[0101] The above designs are examples. Further variants are covered in the patent specification, or claims (e.g., to generators for turbopumps/turbopumps).

DETAILED DESCRIPTION

[0102] FIG. 1 shows a simplified energy diagram.

[0103] Chemical energy (10) is bound in the reducing agent (4)—e.g. H.sub.2 and oxidizing agent (5)—e.g. O.sub.2. The reactants, or the fuel, react in the combustion chamber (3).

[0104] In general, the following applies to chemical engines (0): The conversion of the chemically bound energy (10) provides predominantly thermal energy (11) with lossy conversion (12). Furthermore, kinetic energy (15) is obtained by lossy conversion (16) at the constriction of the nozzle (18) and nozzle itself (19). This is because it is only through the lossy thermodynamic changes of state at the nozzle throat (18) and nozzle (19) that a further part of this thermal energy (11) is converted into kinetic energy (15) in the direction of thrust (14). Further losses occur at the engine, for example, as a result of the expansion at the nozzle outlet (17) not being fully optimal, e.g. due to variable external pressure during vertical takeoff.

[0105] FIG. 2 contains another simplified energy scheme.

[0106] Compared to the embodiment FIG. 1, with the present process and power concept the geometry of the chemical engine (20) is changed in length (reduction of friction, material), diameter (reduction of material) and constriction of the nozzle (28) (reduction of radial acceleration, friction, etc.) and nozzle (29) (reduction of divergence). Alternatively, the combustion chamber (23) can be made tubular or conical, if necessary, to further limit losses.

[0107] For comparison, the design of an engine (0) with a conventional design is shown. This also applies analogously to other engine types such as air-breathing engines (e.g. ramjets).

[0108] During the conversion of chemical energy (10) into thermal energy (21), the energetic losses (22) are minimized by higher reaction rates and, if necessary, metered turbulent combustion or combustion with adapted pressure during combustion. This is supported by the addition of homogeneous catalysts (8), e.g. of platinum. In addition, the combustion chamber (20) can be catalytically coated, or coated with a heterogeneous catalyst, e.g. in the combustion chamber head. By further coating in the rest of the combustion chamber, the heat radiation on the combustion chamber walls can be reduced (reflection). A variable dose rate of injected electromagnetic waves (30)—e.g. in the form of magnetic waves or microwaves, or radio waves can have a targeted effect on the reaction in the combustion chamber (23). Advantageously, the electromagnetic waves are coupled to injected homogeneous catalysts (8). These have corresponding paramagnetic properties with a high electromagnetic absorption capacity. This reduces absorption compared to purely dielectric properties (e.g. of propellants). The property of electromagnetic waves (30) is used, as in the case of microwaves, for example, to increase the reaction rate (Patent application DE 39 03 602 A1) and at the same time reduce the combustion temperature. An electrotechnical supply can optionally be provided by generators on the turbopump, generators on the engine, or by thermocouples on the engine. Electromagnetic waves, e.g. magnetic waves, can also be used to selectively align or equalize the ionized substances in the combustion chamber.

[0109] Due to higher flow velocity, the constriction of the nozzle (28) is reduced. The energetic losses (26) during the conversion of thermal energy (21) into kinetic energy (25) are reduced. Kinematic losses (27) are reduced due to the reduced length and inclination of the nozzle (29). The loads on homogeneous catalysts (8) are adapted to the variable external pressure during vertical starts. Energetic losses are thus further reduced. The speed at the nozzle outlet of the engine can also be controlled and adjusted via injected shafts (30) in the combustion chamber head to further reduce kinematic losses (27) at the nozzle outlet (24) of the engine.

[0110] FIG. 3 shows a Sankey diagram.

[0111] The adapted power concept increases the fraction of a rocket engine (typically 40-70%) or air-breathing engine that can be used as thrust (31). In summary, an alternative to thermo-chemistry is to be achieved by physical-chemical measures, or physico-chemical.

[0112] The kinematic losses (32) can be reduced by modifying the combustion chamber design, but also by adapting the outlet pressure at the nozzle of the engine to the variable external pressure. This is relevant, for example, in the case of a vertical takeoff.

[0113] The thermal losses (33) in the engine are reduced, e.g. by increasing the mass flow rate.

[0114] Wall losses (34) are reduced by adapting the geometry and improving combustion kinetics. In the same context, combustion losses are reduced (35).

[0115] FIG. 4 links other schemes together.

[0116] For the activity of individual catalysts (401), a general tendency is indicated with an increase triangle (4010) is indicated.

[0117] The activity of the catalysts (401) increases in particular with: [0118] 1. higher temperature of the catalyst (4011), [0119] 2. larger specific surface of the catalyst (4012) [0120] 3. proximity to the reaction or to the combustion chamber wall (4013) [0121] 4. possibly with a higher number of different catalysts, since certain catalysts can have a stabilizing or reinforcing effect on one another, e.g. as promoters (4014)

[0122] Also, the overall activity can be increased by higher quantitative concentration of the catalysts (4015) can be increased. Additionally, the activity of the catalyst (401) can be enhanced by electromagnetic dose rate (4016) (e.g., microwaves). Catalysts, such as platinum generally have paramagnetic properties. These properties are superior to pure dielectricity of propellant for coupling electromagnetic dose rate (4016). At the same time, electromagnetic dose rate (4016) can be used to ignite or stimulate the ionized flame front. Also, electromagnetic dose rate increases the activity of catalysts. At the same time, catalysts decrease the required activation energy for chemical reactions. Thus, with concentration of catalysts (4015) and the level of electromagnetic dose rate (4016), two complementary and reinforcing control actuators are available to increase the activity of catalyst (401) to a maximum.

[0123] That means by increasing temperature (4011), specific surface area (4012), proximity to the reaction (4013), number of different catalysts (4014) and quantitative concentration (4015), growth (4019) of activity of catalysts occurs.

[0124] In the reaction area, a reaction chain (402) or an increase in the number of reactions (4021) to the center of the reaction region, e.g., due to an increase in temperature, available activation energy, number of reactive intermediates (e.g., radicals), etc.

[0125] Further on, reaction chains without effective catalysts (402) and reaction chains with effective catalysts (403) are shown. In exothermic reactions (4041), starting products are converted into reaction products. After the supply of activation energy, exothermic reactions release energy. Some of the activation energy can be extracted from the environment, or released energy can be released into the environment. An increase in the activity of the catalysts (401) results in an additional branching at the reaction chain (4022). On the one hand, the required activation energy can be reduced by catalysts. On the other hand, in exothermic reactions additional reaction enthalpy is released in the same time due to higher reaction rates.

[0126] For this purpose, the control system of the combustion chamber (404), or the basic tendencies of the reaction are shown in generalized form. The tendencies of the reaction (404) are decisively usable for the design and operation of the combustion chambers. This is the object of invention of this adapted process concept. An energetic optimization of process parameters (e.g. pressure and temperature) and combustor geometries (e.g. the necking) is aimed at.

[0127] In this embodiment, some parameters can be increased with increase of the actuators (4010 and 4016), with conventional isobaric change of state (4050). The parameters to be increased in this embodiment are reaction speed (4040) and pressure (4041). In an alternative embodiment, the pressure can be stabilized, for example, or lowered. On the other hand, parameters such as temperature (4042) and number of free reactants (4043), e.g. unburned components, or also pollutants produced, can also be lowered. Increasing the actuators of the control system (4010 and 4016) results in a decreasing tendency (4029). The associated tendency for this change of state is isobaric (4050). In an alternative embodiment, the temperature can alternatively be increased or stabilized in the event of a large increase in the reacting material flow.

[0128] In an alternative embodiment, a superadiabatic reaction may also be can be brought about at a temperature above the reaction temperature under stoichiometric conditions.

[0129] In principle, by adding catalysts, not only can the completeness of the reaction be aimed at, but also, in addition, the reaction rate can be increased if the loads are further increased. This has the effect of lowering the activation energy as well as the temperature of the combustion chamber. And it allows to increase the mass flow.

[0130] Optionally, the temperature can be lowered and, in particular, the reaction temperature can be increased to superadiabatic conditions if the catalytic activity and mass flow are appropriate. In this case, reaction temperatures can be achieved which are higher than the temperature under stoichiometric conditions [10] [11] [14]. Heterogeneous catalysts with high thermal conductivity can be used for this purpose.

[0131] Alternatively, it is also possible to control the pressure and speed of the supporting agent.

[0132] This is supported by electromagnetic waves (e.g. microwaves), which can further adjust the trend of the reactions.

[0133] FIG. 5 illustrates a scheme for laminar combustion.

[0134] Laminar combustion takes place in the combustion chamber (3) under uniform conditions. Fuel is injected (51) into the combustion chamber (3). Between the unburned fuel (52) and the burned fuel (54) there is a uniform zone of combustion (53). However, trailing flame fronts (or pressure surges) and leading pressure surges can cancel each other out or reduce each other. In the worst case, this can result in energy losses.

[0135] The result is a uniform situation in the direction of propagation (55).

[0136] FIG. 6 illustrates various basic shapes for combustion chambers according to [1].

[0137] In this FIG. various basic shapes for combustion chambers are shown.

[0138] An engine (70) is often manufactured with a cylindrical combustion chamber (71). With cylindrical combustion chamber (71), combustion is accelerated to the critical area (72) to the critical Mach number. In FIG. 6, the dimension arrows are shown closed. Above the critical Mach number, thermal acceleration is no longer possible and further acceleration takes place in the Laval nozzle (73) with corresponding efficiency. Laval nozzle (73) enables partial conversion of thermal energy into kinetic energy to achieve the highest possible thrust. At the Laval nozzle (73), part of the energy in the engine (70) is transferred thermally to the nozzle wall. Another part cannot be further converted into usable kinetic energy (74) due to friction in the engine (70) and transverse acceleration at the incision (71) and expansion of the nozzle (72). The usable vector components (741) and the resulting force components (742) are shown in simplified form in the sectional plane of the drawing. In the spatial representation, further components arise which cannot be used energetically in thrust. The vectors are each shown with arrowheads open on one side.

[0139] Similarly, in a spherical combustion chamber (75) and in a pear-shaped combustion chamber (76), the flow cross-section is first narrowed (71) and then widened (72) in the nozzle.

[0140] FIG. 7 illustrates a schematic for heat reflections off a catalytic coating.

[0141] In this general embodiment, the principle of heat reflection is shown very roughly. The combustion chamber wall (151) is catalytically coated (152). In addition to the advantages for the chemical reaction of oxidizer and reducing agent (155), e.g. with increased mass flows, the coating can also influence the thermal properties of the combustion chamber wall (151).

[0142] In this general embodiment, the principle of heat reflection is shown very roughly. The combustion chamber wall (151) is catalytically coated (152). In addition to the advantages for the chemical combustion of oxidizer and reducing agent (155), the coating can also influence the thermal properties of the combustion chamber wall (151).

[0143] Gold, for example, has a high reflectivity in the infrared range even at low layer thicknesses. However, gold is mechanically soft and platinum, for example, is generally better suited for more aggressive environments.

[0144] In this embodiment, an alloy of 55% platinum with 45% rhenium is preferred for the catalytic coating in accordance with patent specification U.S. Ser. No. 17/650,537. The permissible melting temperature of the alloy is over 2,673° K or 2,400° C. As a result, the alloy has a high resistance to sintering and premature damage to the catalytic activity. In addition, rhenium has positive mechanical properties and an effect against coking. The coating thickness is a maximum of 100 μm, but at least 2 μm to effectively reflect thermal radiation.

[0145] By additionally introducing homogeneous catalysts (156) into the fuel (155), the catalytic coating (152) of the combustion chamber wall (151) is refreshed and protected as far as possible against fouling/coating.

[0146] Thermal radiation (153) onto the combustion chamber wall (151) is reflected (154) by the catalytic coating (152). Thermal losses are reduced and the cooling of the combustion chamber (151) is relieved.

[0147] What is described herein are specific examples of possible variations on the same invention and are not intended in a limiting way. The invention can be practiced using other variations not specifically described above.