Thermal drive electric energy combustion mode regulation and control system and method based on ramjet engine

Abstract

The invention relates to a thermal drive electric energy combustion mode regulation and control system and method based on a ramjet engine. Comprising a concave cavity type engine, and a thermoelectric conversion assembly is arranged on the wall face of a combustion chamber of the concave cavity type engine; an electric excitation regulation and control assembly is arranged in a concave cavity of the concave cavity type engine; the thermoelectric conversion assembly is electrically connected with the electric excitation regulation and control assembly, absorbs heat of the wall face of the combustion chamber and converts the heat into electric energy. The electric energy is transmitted to the electric excitation regulation and control assembly, the electric excitation regulation and control assembly conducts electric excitation regulation and control, air ionization is promoted, and large-scale local turbulent flow in the combustion chamber is caused. Through the combined design of the thermoelectric conversion assembly and the electric excitation regulation and control assembly, harmful waste heat on the wall face of the combustion chamber can be effectively absorbed and converted into electric energy, the electric energy is transmitted to the electric excitation regulation and control assembly, and through the electric excitation effect, the fuel penetration depth is increased, the mixing efficiency of the fuel and air mainstream is enhanced, and the combustion characteristic is improved; the fuel utilization rate is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of combustion control, and in particular to a thermal drive electric energy combustion mode control system and method based on a ramjet engine. Background Art

[0002] In aircraft, ramjets are primarily used to organize combustion within the incoming airflow and are a key power unit for achieving cruise flight. Ramjets typically need to operate within a wide range of incoming airflow velocities and are expected to achieve stable operation across a wide speed range. Matching their combustion mode with intake conditions is a major technical challenge, especially when engine operating conditions fluctuate dramatically, making it difficult for the combustion chamber to maintain efficient and stable operation. In the face of wide-range operation, extreme operating conditions, combustion oscillations, and other issues, combustion control methods are often required to regulate the combustion mode, thereby ensuring efficient and stable operation of the ramjets across a wide speed range.

[0003] Traditional combustion control technologies are mostly implemented through variable geometry or multi-stage injection. While adding a variable geometry control mechanism to a ramjet engine design with a variable mechanical geometry easily allows for this, it significantly increases the complexity of the combustion chamber configuration and the takeoff weight. Mechanical control suffers from time-to-market issues. Overly rapid control can easily cause abrupt changes in the flow field state, while insufficient or excessive air can directly lead to rich or lean burn and flameout. Overly slow control, on the other hand, introduces hysteresis in the system response, preventing rapid response to control issues, resulting in control delays or even failure. It also introduces unnecessary flow disturbances, exacerbating unsteady combustion processes and reducing scramjet performance. Multi-stage injection can effectively achieve combustion enhancement. However, it is often coupled with multi-stage flame stabilizers, resulting in significant total pressure losses and reduced engine thrust. Furthermore, the hysteresis effect of combustion mode transitions can even have negative effects, reducing engine performance. Furthermore, it fails to fully achieve ideal control states and lacks real-time control capabilities. Summary of the Invention

[0004] Based on this, it is necessary to provide a ramjet-based thermal drive electric combustion mode control system and method that can solve the problems of unstable control effect, slow response and complex system in response to the above technical problems.

[0005] A thermal drive electric energy combustion mode control system based on a ramjet engine includes a cavity engine, a thermoelectric conversion component is provided on the combustion chamber wall of the cavity engine; an electric excitation control component is provided in the cavity of the cavity engine; The thermoelectric conversion component is electrically connected to the electric excitation regulation component. The thermoelectric conversion component absorbs heat from the combustion chamber wall and converts it into electrical energy. The electrical energy is transmitted to the electric excitation regulation component, which performs electric excitation regulation to promote air ionization and cause large-scale local turbulence in the combustion chamber.

[0006] In one embodiment, the thermoelectric conversion component is arranged on a side of the combustion chamber wall away from the combustion chamber cavity.

[0007] In one embodiment, the thermoelectric conversion assembly is located near the fuel cooling pipeline; one side of the thermoelectric conversion assembly is close to the combustion chamber wall, and the other side is close to the fuel cooling pipeline.

[0008] In one embodiment, the thermoelectric conversion assembly includes a thermoelectric conversion unit, and the thermoelectric conversion unit includes a plurality of thermoelectric conversion modules connected in series. The plurality of thermoelectric conversion modules connected in series are laid along the length direction of the fuel cooling pipeline and / or along the width direction of the combustion chamber.

[0009] In one embodiment, there are more than two thermoelectric conversion units, and the more than two thermoelectric conversion units are stacked and connected in series.

[0010] In one embodiment, the thermoelectric conversion component is made of thermoelectric power generation material, the cold source of the thermoelectric power generation material for thermoelectric power generation is the temperature of the fuel flowing from the fuel tank to the combustion chamber fuel cooling pipeline, and the heat source is the thermal energy of the combustion chamber wall.

[0011] In one embodiment, the electrical excitation control component includes a multi-channel tip discharge excitation device, and the multi-channel tip discharge excitation device is arranged on the bottom wall of the cavity.

[0012] In one embodiment, the electric excitation control component further includes a cascade electric excitation device, and the cascade electric excitation device is arranged on a side wall perpendicular to the combustion chamber cavity.

[0013] In one embodiment, the electric excitation control component further includes a cascade electric excitation device, and the cascade electric excitation device is arranged on a vertical surface of the leading edge of the combustion chamber cavity.

[0014] A method for controlling a thermal drive electric energy combustion mode based on a ramjet engine, the method comprising: During the operation of the ramjet engine, the fuel in the fuel tank flows into the fuel cooling pipeline after passing through the fuel pump. The thermoelectric conversion component absorbs cold energy from the fuel cooling pipeline on one side and absorbs heat energy from the combustion chamber wall on the other side, generating electricity through the temperature difference. The electrical energy is transmitted to the electric excitation control component, which generates a strong electric field to electrically excite and control the air in the combustion chamber, promote air ionization, and cause large-scale local turbulence in the combustion chamber.

[0015] Compared with the existing technology, the thermal drive electric energy combustion mode control system and method based on the ramjet engine provided by the present invention has the following effects: 1. The combined design of the thermoelectric conversion component and the electric excitation control component absorbs harmful waste heat from the combustion chamber wall through the thermoelectric conversion component and converts it into electrical energy, which can avoid the generation of local high temperatures in the combustion chamber and suppress unstable combustion. At the same time, the generated electrical energy is provided to the electric excitation control component without the need for an additional power system, resulting in a simple structure. The electric excitation control component can produce a strong ionization effect through electrical excitation, thereby increasing the fuel penetration depth, enhancing its mixing efficiency with the mainstream air, improving combustion characteristics, and increasing fuel utilization. Through this combined design, the thermoelectric conversion component can provide a large amount of sustainable electrical energy for the electric excitation control component.

[0016] 2. The electric excitation control component can cause large-scale local turbulence in the combustion chamber. Through the electric excitation control component, electric excitation control can be performed to accurately control the combustion mode, suppress unstable combustion, thermoacoustic oscillations and other adverse phenomena, and achieve a more stable combustion process.

[0017] 3. Harmful waste heat from the combustion chamber wall is absorbed by the thermoelectric conversion component, and the combustion mode is optimized by the electric excitation control component to achieve more complete combustion, which can reduce pollutants produced by incomplete combustion, is low-carbon and environmentally friendly, and also realizes efficient energy utilization and active control of the combustion mode. It has high integration and is applicable to a wide range of scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0019] Figure 1 A schematic diagram of the structure of a thermal drive electric energy combustion mode control system based on a ramjet engine in one embodiment; Figure 2 A schematic diagram of the structure of a thermoelectric conversion component in one embodiment; Figure 3 A schematic diagram of the structure of an electric excitation control component in one embodiment; Figure 4 Schematic diagram of flame transient comparison under conditions of excitation and no excitation in one embodiment, wherein: Figure 4 (a) is a schematic diagram of flame transient without excitation. Figure 4 (b) Schematic diagram of flame transient under excitation conditions.

[0020] Description of reference numerals: Combustion chamber wall 1, thermoelectric conversion component 2, thermoelectric conversion module 21, electric excitation control component 3, multi-channel tip discharge excitation device 31, cascade electric excitation device 32, fuel cooling pipeline 4.

[0021] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0022] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0023] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0024] In the present invention, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; it can mean mechanical connection, electrical connection, physical connection, or wireless communication connection; it can mean direct connection or indirect connection through an intermediate medium; it can mean internal communication between two elements or interaction between two elements, unless otherwise specified. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] It can be understood that the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in this field can implement it. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0026] The following describes the implementation of the present invention in detail with reference to the accompanying drawings in the embodiments of the present invention.

[0027] Example 1 Understandably, traditional combustion control technologies are mostly based on passive structures, inducing the flow field to self-regulate by changing the geometric configuration and injection strategy. However, passive control methods often suffer from hysteresis, resulting in slow combustion flow field response and poor control effectiveness. They can also easily cause additional combustion flow field instability during the control process, leading to negative effects. Traditional dielectric barrier discharge technology, on the other hand, suffers from low power density per unit volume. The ion wind it generates has little effect on supersonic incoming flow, and its effect on combustion mode control is limited. Furthermore, it lacks ignition capability and is usually used in combination with other discharge forms.

[0028] Based on this, the present invention addresses the issues of excessive wall waste heat, high power requirements, and the difficulty in controlling flameout and combustion mode transitions during ramjet engine operation. By integrating cooling, power generation, and combustion control, the system proposes a highly efficient system. The core of the system lies in converting engine waste heat into a "waste-to-treasure" method to enhance combustion, and in the design of a highly efficient integrated "heat-electric-control" engine system. This system is embodied in two key components: a thermoelectric conversion component that removes the significant waste heat generated by the engine's combustion chamber walls, and an electrically actuated control component that uses the generated electricity to control combustion modes.

[0029] See Figures 1 to 4 This embodiment provides a thermal drive electric energy combustion mode control system based on a ramjet engine, including a cavity engine, wherein a thermoelectric conversion component 2 is provided on a combustion chamber wall 1 of the cavity engine; an electric excitation control component 3 is provided in a cavity of the cavity engine; the thermoelectric conversion component 2 and the electric excitation control component 3 are electrically connected, the thermoelectric conversion component 2 absorbs heat from the combustion chamber wall 1 and converts it into electric energy; the thermoelectric conversion component 2 transmits the electric energy to the electric excitation control component 3, and the electric excitation control component 3 performs electric excitation control to promote air ionization, causing large-scale local turbulence in the combustion chamber, thereby realizing sustainable operation of the ramjet engine over a wide speed range.

[0030] This invention utilizes a thermoelectric conversion assembly mounted on the outside of the engine combustion chamber wall 1 to convert waste heat from the combustion chamber wall 1 into electrical energy, providing a stable power source for electrical excitation. The electrical excitation control assembly 3 is integrated with the engine combustion chamber structure. During ramjet operation, this assembly improves mixing, enhances localized heat release, and increases the number of active particles, enabling regulation of the flame heat release zone and combustion mode, thereby optimizing ramjet performance. The system designed in this invention can simultaneously meet the power requirements for both thermal protection and electrical excitation control of supersonic combustion.

[0031] Specifically, the thermoelectric conversion assembly 2 is positioned on the side of the combustion chamber wall away from the combustion chamber cavity, near the fuel cooling line 4. One side of the assembly is close to the combustion chamber wall 1, and the other side is close to the fuel cooling line 4. In other words, the thermoelectric conversion assembly 2 is positioned between the fuel cooling line 4 and the combustion chamber wall 1 to facilitate the acquisition of both cooling and heating sources, thereby facilitating thermoelectric power generation.

[0032] The thermoelectric conversion assembly 2 comprises a thermoelectric conversion unit, each of which includes several series-connected thermoelectric conversion modules 21. These modules 21 are arranged along the length of the fuel cooling line and / or the width of the combustion chamber. Specifically, the thermoelectric conversion unit is a single layer, and the thermoelectric conversion modules 21 within the unit are arranged as needed. They can be laid out in a long strip along the path of the fuel cooling line 4, or they can be extended across the width of the combustion chamber to form a flat surface to better absorb the heat sink. Furthermore, two or more thermoelectric conversion units can be stacked in series. This stacking and series arrangement enhances the heat absorption of the thermoelectric conversion assembly 2. This compact arrangement can replace large power sources to power electrically stimulated combustion, reduce flight structure mass, and achieve efficient space utilization. The thermoelectric conversion assembly 2 is made of thermoelectric materials. The heat sink for thermoelectric power generation is the temperature of the fuel flowing from the fuel tank to the combustion chamber fuel cooling line 4, and the heat source is the thermal energy of the combustion chamber wall 1. It is worth noting that the voltage, frequency and other parameters of the electric energy output by the thermoelectric conversion component 2 are adjusted according to specific application requirements.

[0033] The electric excitation control component 3 includes a multi-channel tip discharge excitation device 31 and a cascade electric excitation device 32. It can be understood that the cavity has a front edge, a front wall, a bottom wall, a rear wall and other parts, and the multi-channel tip discharge excitation device 31 is arranged on the bottom wall of the cavity. The cascade electric excitation device 32 is arranged on the side wall perpendicular to the combustion chamber cavity, or on the vertical surface of the front edge of the combustion chamber cavity, and is arranged according to the specific situation. It is worth noting that the side wall perpendicular to the combustion chamber cavity refers to the surface on the left and right sides of the cavity that is perpendicular to the length direction or depth direction of the cavity in three-dimensional space.

[0034] The multi-channel tip discharge excitation device 31 is disc-shaped and made of insulating material. It is designed with multiple discharge channels, each with a specially designed tip electrode. These electrodes are typically made of metal and have sharp shapes, such as needles or thin columns, to facilitate charge accumulation at the tips, generating a strong electric field. The electrodes on the disc are spaced apart to maintain a certain distance and insulation to prevent interference or short circuits between channels. The thermoelectric conversion assembly 2 provides a high-voltage power supply to the multi-channel tip discharge excitation device 31, ionizing the air or other medium surrounding the electrodes to form a plasma. When the high-voltage power supply is turned on, an extremely strong electric field is formed near the tip electrodes, ionizing the surrounding gas molecules and generating plasma. The electrons and ions in the plasma are accelerated by the electric field and collide with other gas molecules, further generating more ions and electrons, forming a plasma discharge. The multi-channel tip discharge excitation device 31 uses electrical excitation to generate tip discharge, resulting in higher energy density. This allows for enhanced fuel mixing near the walls of the mainstream flow channel, allowing for real-time control of the combustion mode and flame heat release location.

[0035] The cascade electric excitation device 32 is formed by cascading a plurality of identical or similar electric excitation units. The cascade electric excitation device 32 in this embodiment is formed by cascading five electric excitation units. The cascade electric excitation device 32 is provided with a control circuit, which controls and monitors the working state of the electric excitation unit so as to adjust the frequency, amplitude, phase and other parameters of the excitation signal. During operation, the control circuit modulates and controls the electric signal according to the set parameters, and then the electric excitation unit generates the required excitation signal. The excitation signal generates an electric field in the combustion chamber. Through electric field excitation, the position and intensity of the flame heat release zone can be adjusted, effectively improving fuel utilization efficiency, broadening the engine operating speed range, achieving stable combustion flames under extreme working conditions, and improving the robustness of the engine combustion chamber under a wide range of working conditions.

[0036] As can be understood, electrical excitation offers the advantages of rapid control of combustion modes, significantly enhanced mixing effects, and a wide range of flame heat release position control. By employing the multi-channel tip discharge excitation device 31 and the cascaded electrical excitation device 32 separately or simultaneously, it is possible to promote air ionization, inject heat and active substances into the combustion system in a targeted manner, and achieve large-scale control of the flame heat release zone position, thereby enabling switching between multiple combustion modes and enhancing the combustion dynamics process.

[0037] In one of the embodiments, the thermal drive electric energy combustion mode control system based on the ramjet engine proposed in the present invention is verified.

[0038] Typical test transient flame contrast Figure 4 As shown. After the cavity flame is established in the combustion chamber, Figure 4As shown in (a), when no electrical excitation is applied, the flame heat release is weak and the heat release area is concentrated in the cavity shear layer. The leading edge of the flame heat release area is anchored at the cavity step. At this time, the combustion mode is the cavity shear layer flame stabilization mode. Figure 4 As shown in Figure 2 (b), when electrical excitation is applied upstream of the cavity, it promotes local fuel ionization, enhances fuel-air mixing, and raises the local temperature, thereby promoting the forward propagation of the flame heat release zone to the isoelectric excitation influence zone. Simultaneously, the flame heat release intensity is enhanced, and the combustion mode at this point transitions to the jet wake flame stabilization mode. Once the electrical excitation is turned off, the flame combustion mode reverts to the cavity shear layer flame stabilization mode. This demonstrates that the proposed ramjet-based thermal drive electric energy combustion mode control system can achieve instant and effective combustion mode control.

[0039] Example 2 This embodiment provides a method for controlling a thermal drive electric energy combustion mode based on a ramjet engine, the method comprising: During the operation of the ramjet engine, the fuel in the fuel tank flows into the fuel cooling pipeline after passing through the fuel pump. One side of the thermoelectric conversion component absorbs the cold source from the fuel cooling pipeline, and the other side absorbs heat energy from the combustion chamber wall, generating electricity through the temperature difference.

[0040] The electrical energy is transmitted to the electric excitation control component, which generates a strong electric field to electrically excite and control the air in the combustion chamber, promote air ionization, and cause large-scale local turbulence in the combustion chamber.

[0041] It is worth noting that a strong electric field refers to an electric field strength that can break through the air and discharge.

[0042] In this embodiment, the specific operating process and operating principle of the thermal drive electric energy combustion mode control method for ramjet engines are the same as those of the system in Example 1, and therefore will not be further described in this embodiment. The method described herein can be implemented in whole or in part using the system in Example 1.

[0043] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0044] The above-described embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that a person skilled in the art would be able to make numerous modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A thermal drive electric energy combustion mode control system based on a ramjet engine, comprising a cavity engine, characterized in that: A thermoelectric conversion component is arranged on the combustion chamber wall of the cavity-type engine; an electric excitation control component is arranged in the cavity of the cavity-type engine; The thermoelectric conversion component is electrically connected to the electric excitation regulation component. The thermoelectric conversion component absorbs heat from the combustion chamber wall and converts it into electrical energy. The electrical energy is transmitted to the electric excitation regulation component, and the electric excitation regulation component performs electrical excitation regulation to promote air ionization and cause large-scale local turbulence in the combustion chamber.

2. The thermal drive electric energy combustion mode control system based on ramjet engine according to claim 1 is characterized in that: The thermoelectric conversion assembly is arranged on a side of the combustion chamber wall away from the combustion chamber cavity.

3. The thermal drive electric energy combustion mode control system based on ramjet engine according to claim 1 or 2, characterized in that: The thermoelectric conversion assembly is located near the fuel cooling pipeline; One side of the fuel cooling pipe is close to the combustion chamber wall, and the other side of the fuel cooling pipe is close to the combustion chamber wall.

4. The thermal drive electric energy combustion mode control system based on ramjet engine according to claim 3 is characterized in that: The thermoelectric conversion assembly includes a thermoelectric conversion unit, and the thermoelectric conversion unit includes a plurality of thermoelectric conversion modules connected in series. The plurality of thermoelectric conversion modules connected in series are laid along the length direction of the fuel cooling pipeline and / or along the width direction of the combustion chamber.

5. The thermal drive electric energy combustion mode control system based on ramjet engine according to claim 4 is characterized in that: There are more than two thermoelectric conversion units, and the more than two thermoelectric conversion units are stacked and connected in series.

6. The thermal drive electric energy combustion mode control system based on ramjet engine according to claim 4 or 5, characterized in that: The thermoelectric conversion assembly is made of a temperature difference power generation material. The cold source of the temperature difference power generation material is the temperature of the fuel flowing from the fuel tank to the combustion chamber fuel cooling pipeline, and the heat source is the heat energy of the combustion chamber wall.

7. The thermal drive electric energy combustion mode control system based on ramjet engine according to claim 1 is characterized in that: The electrical excitation control component includes a multi-channel tip discharge excitation device, and the multi-channel tip discharge excitation device is arranged on the bottom wall of the cavity.

8. The thermal drive electric energy combustion mode control system based on ramjet engine according to claim 7 is characterized in that: The electric excitation control component also includes a cascade electric excitation device, which is arranged on a side wall perpendicular to the combustion chamber cavity.

9. The thermal drive electric energy combustion mode control system based on ramjet engine according to claim 7 is characterized in that: The electric excitation control component also includes a cascade electric excitation device, which is arranged on the vertical surface of the front edge of the combustion chamber cavity.

10. A method for regulating the thermal drive electric energy combustion mode based on a ramjet engine, characterized in that: The method comprises: During the operation of the ramjet engine, the fuel in the fuel tank flows into the fuel cooling pipeline after passing through the fuel pump. The thermoelectric conversion component absorbs the cold source from the fuel cooling pipeline on one side and absorbs the heat energy from the combustion chamber wall on the other side, and generates electricity through the temperature difference. The electrical energy is transmitted to the electric excitation regulation component, which generates a strong electric field to electrically excite and regulate the air in the combustion chamber, promote air ionization, and cause large-scale local turbulence in the combustion chamber.

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