Two-phase ramjet underwater propulsion system with non-condensable gas

Abstract

The invention discloses a two-phase ramjet underwater propulsion system containing non-condensable gas, including a two-phase ramjet underwater propeller, a steam generator and a non-condensable gas generating device; the two-phase ramjet underwater propeller includes an air intake assembly, a steam flow channel and a non-condensable gas flow channel; the front end of the air intake assembly includes a water intake flow channel; the steam flow channel is arranged on the side wall of the air intake assembly perpendicularly to the axis of the air intake assembly, and the air outlet end of the steam flow channel is arranged at the tail end of the air intake assembly; the non-condensable gas flow channel is coated on the periphery of the steam flow channel, and the non-condensable gas enters the water intake flow channel through the outer wall of the steam flow channel and the inner wall of the non-condensable gas flow channel; the air outlet of the steam generator is connected to the air intake end of the steam flow channel; the air outlet of the non-condensable gas generating device is connected to the air intake end of the non-condensable gas flow channel. By using steam as a power source, the propulsion function is realized based on the steam-water direct contact condensation supercharging principle, and the propulsion efficiency and stability are improved by injecting a trace amount of non-condensable gas.

Description

Technical Field

[0001] The invention relates to the field of underwater propulsion devices, in particular to a two-phase ram pressure underwater propulsion system containing non-condensable gas. Background Art

[0002] Currently, the commonly used underwater propulsion methods include propeller thrusters (propellers, pump jets, etc.) and water jet thrusters. Both propulsion methods achieve liquid pressurization through rotating blades to achieve the purpose of propulsion. Both have the following two problems: 1) Due to the presence of rotating parts, these two propulsion methods are subject to speed restrictions due to cavitation limitations and are not suitable for high-speed vehicles near the water surface; 2) Due to the presence of rotating parts, the probability of failure is significantly increased. In particular, when there are a large number of large impurities or mesh debris in the water, blade collision, entanglement and other damage may occur, resulting in reduced propulsion function or even failure.

[0003] The concept of underwater two-phase propulsion originates from air jet propulsion devices, such as ramjet engines, pulse jet engines, and turbojet engines. The fuel of underwater two-phase propulsion devices is usually compressible gas, and in some cases it is a water-reactive compound. Underwater two-phase propulsion devices generate thrust by converting gas potential energy into axial kinetic energy. Compressible bubbles are injected into the working medium water, and the bubble expansion does work on the water. The two-phase mixture is ejected at high speed through the nozzle to generate thrust. A significant advantage of this propulsion device is that it has no movable mechanical parts, eliminating complex structures such as shaft systems and gears, allowing flexible design in the internal space of the ship. The underwater two-phase ramjet engine has no moving parts in contact with water, and is a relatively simple device system. After the water enters the expansion section, the speed decreases and the static pressure increases. High-pressure gas is introduced at the entrance of the mixing chamber. The ventilation pressure is higher than the water pressure. The gas and water are mixed to form a bubbly gas-liquid two-phase flow. Along the axial direction of the nozzle, the pressure of the mixture decreases, the bubbles expand, and the gas-liquid two-phase bubbly mixture accelerates. The expansion of the bubble does work on the object, forming a high-speed water jet, which in turn generates thrust.

[0004] However, underwater two-phase thrusters have certain requirements for compressible gases used as fuel. Ordinary compressible gases may experience significant changes in physical properties within the temperature range of seawater and steam, or react with seawater. They have a certain solubility in seawater and may produce certain impurities or mesh debris during operation, which will have a certain impact on the operation of the thruster itself.

[0005] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] The purpose of the present invention is to provide a two-phase ramjet underwater propulsion system containing non-condensable gas, which uses steam as a power source, realizes the propulsion function based on the steam-water direct contact condensation pressurization principle, and improves the propulsion efficiency and stability by injecting a trace amount of non-condensable gas.

[0007] To achieve the above-mentioned purpose, the present invention provides a two-phase ramjet underwater propulsion system containing non-condensable gas, comprising a two-phase ramjet underwater propeller, a steam generator and a non-condensable gas generating device; the two-phase ramjet underwater propeller comprises an air intake assembly, a steam flow channel and a non-condensable gas flow channel; the front end of the air intake assembly comprises a water intake flow channel; the steam flow channel is arranged on the side wall of the air intake assembly perpendicular to the axis of the air intake assembly, and the air outlet end of the steam flow channel is arranged at the rear end of the air intake assembly; the non-condensable gas flow channel is coated on the periphery of the steam flow channel, and the non-condensable gas enters the water intake flow channel through the outer wall of the steam flow channel and the inner wall of the non-condensable gas flow channel; the air outlet of the steam generator is connected to the air intake end of the steam flow channel; the air outlet of the non-condensable gas generating device is connected to the air intake end of the non-condensable gas flow channel.

[0008] In a preferred embodiment, the two-phase ramjet underwater thruster also includes an inner flow channel assembly, a front assembly and a tail spray assembly; the inner flow channel assembly is detachably and coaxially embedded in the central channel of the air intake assembly; the rear end of the front assembly is detachably connected to the front end of the air intake assembly and the inner flow channel assembly, and the water inlet channel is coaxially arranged inside the inner flow channel assembly and the front assembly; the front end of the tail spray assembly is detachably connected to the rear end of the air intake assembly; wherein the inner flow channel assembly, the front assembly, the air intake assembly and the tail spray assembly are coaxially arranged.

[0009] In a preferred embodiment, the inner flow channel component includes a plurality of groups of non-condensable gas exhaust holes, which are evenly arranged on the side wall of the inner flow channel component, and each group of non-condensable gas exhaust holes is arranged along the axial direction of the inner flow channel component.

[0010] In a preferred embodiment, the aperture of each group of non-condensable gas exhaust holes increases gradually from the front end to the rear end of the inner flow channel component, and the axis of the non-condensable gas exhaust holes forms an inclination angle with the axis of the water inlet flow channel.

[0011] In a preferred embodiment, the non-condensable gas enters the water inlet flow channel after passing through the non-condensable gas flow channel and the non-condensable gas exhaust hole.

[0012] In a preferred embodiment, the air intake assembly further includes a steam supersonic flow channel, which is arranged in a ring inside the side wall of the air intake assembly, one end of the steam supersonic flow channel is connected to the steam flow channel, and the other end is connected to the tail nozzle assembly from the tail end of the air intake assembly.

[0013] In a preferred embodiment, the tail nozzle assembly includes a mixing chamber and a tail nozzle; the mixing chamber is arranged at the front of the tail nozzle assembly, and the mixing chamber is connected to the steam supersonic flow channel; the tail nozzle is arranged at the rear of the tail nozzle assembly, and the tail nozzle has a flared structure with a small front and a large rear, and the tail nozzle is coaxially arranged with the mixing chamber.

[0014] In a preferred embodiment, the tail spray assembly further includes a plurality of water flow exchange holes, which are evenly distributed and arranged on the outer wall of the mixing chamber of the tail spray assembly.

[0015] In a preferred embodiment, the two-phase ramjet underwater propulsion system containing non-condensable gas also includes a steam regulating valve, which is arranged at the connection between the outlet of the steam regulating valve and the air inlet end of the steam flow channel, and the steam flow channel is used to regulate the flow rate of the intake air entering the steam flow channel.

[0016] In a preferred embodiment, the two-phase ramjet underwater propulsion system containing non-condensable gas also includes a non-condensable gas regulating valve, which is arranged at the connection between the air outlet of the non-condensable gas generating device and the air inlet end of the non-condensable gas flow channel, and the non-condensable gas regulating valve is used to adjust the flow rate of the non-condensable gas entering the non-condensable gas flow channel.

[0017] Compared with the prior art, the two-phase ramjet underwater propulsion system containing non-condensable gas of the present invention has the following beneficial effects: the new two-phase ramjet propulsion device uses steam as a power source, realizes the propulsion function based on the steam-water direct contact condensation supercharging principle, and improves the propulsion efficiency and stability by injecting a trace amount of air. The new two-phase ramjet propulsion device has a complex structure, including complex local structures such as air injection holes, steam nozzles, steam flow channels, air flow channels, and tail nozzles. At the same time, the compact arrangement makes its integrated processing difficult, especially the internal non-condensable gas exhaust holes are difficult to process. Compared with traditional propeller thrusters or water jet thrusters, the two-phase ramjet underwater propulsion system proposed in this patent has a simple structure, no rotating parts, has obvious advantages in anti-cavitation, and can be suitable for high-speed aircraft; the propulsion system proposed in this patent has no rotating parts, bearings and other complex components, and its reliability is also significantly improved, and the large area flow channel structure in the middle is not afraid of large debris in seawater; in addition, for large nuclear-powered aircraft, the propulsion system proposed in this patent can directly utilize the steam generated by nuclear heat, without the need for a complex thermoelectric conversion system in the middle, which can improve the power density of the power system of large nuclear-powered aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of the structural arrangement of a two-phase ramjet underwater propulsion system according to an embodiment of the present invention;

[0019] Figure 2 is a schematic front cross-sectional view of a two-phase ramjet underwater thruster according to an embodiment of the present invention;

[0020] Figure 3 is a side view schematic diagram of a two-phase ramjet underwater thruster according to an embodiment of the present invention;

[0021] Figure 4 1 is a schematic top view of a two-phase ramjet underwater thruster according to an embodiment of the present invention.

[0022] Description of main reference numerals:

[0023] 1-steam generator, 2-non-condensable gas generating device, 3-steam regulating valve, 4-non-condensable gas regulating valve, 5-steam flow channel, 6-non-condensable gas flow channel, 7-steam supersonic flow channel, 8-water inlet flow channel, 9-non-condensable gas exhaust hole, 10-non-condensable gas exhaust channel, 11-water flow exchange hole, 12-mixing chamber, 13-tail nozzle, 20-inner flow channel assembly, 30-front assembly, 40-near air inlet assembly, 50-tail nozzle assembly. DETAILED DESCRIPTION

[0024] The specific implementation modes of the present invention are described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific implementation modes.

[0025] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising”, etc., will be understood to include the stated elements or components but not to exclude other elements or components.

[0026] like Figure 1 As shown, a two-phase ramjet underwater propulsion system containing non-condensable gas according to a preferred embodiment of the present invention includes a two-phase ramjet underwater propulsion device, a steam generator 1 and a non-condensable gas generating device 2; the two-phase ramjet underwater propulsion device includes an air intake component 40, a steam flow channel 5 and a non-condensable gas flow channel 6; the front end of the air intake component 40 includes a water inlet flow channel 8; the steam flow channel 5 is arranged on the side wall of the air intake component 40 perpendicular to the axis of the air intake component 40, and the air outlet end of the steam flow channel 5 is arranged at the tail end of the air intake component 40; the non-condensable gas flow channel 6 is coated on the periphery of the steam flow channel 5, and the non-condensable gas enters the water inlet flow channel 8 through the outer wall of the steam flow channel 5 and the inner wall of the non-condensable gas flow channel 6; the air outlet of the steam generator 1 is connected to the air intake end of the steam flow channel 5; the air outlet of the non-condensable gas generating device 2 is connected to the air intake end of the non-condensable gas flow channel 6.

[0027] In some embodiments, the non-condensable gas generating device 2 of this embodiment adopts a high-pressure gas cylinder, which is a high-pressure gas cylinder carried by the aircraft. Since the injection volume is relatively small, in order to simplify the composition of the propulsion system, the aircraft can replace the high-pressure gas cylinder before each voyage to ensure the supply of non-condensable gas. Of course, the aircraft can also be equipped with a special non-condensable gas generating device 2 to realize the supply of non-condensable gas. At the same time, the non-condensable gas referred to in the present invention refers to a gas that does not react with seawater, does not show obvious changes in physical properties within the temperature range of seawater and steam, and has a low solubility in seawater, which can be air, nitrogen, etc.

[0028] like Figures 1 to 4 As shown, in some embodiments, the two-phase ramjet underwater thruster also includes an inner flow channel component 20, a front component 30 and a tail spray component 50; the inner flow channel component 20 is detachably and coaxially embedded in the central channel of the air intake component 40; the rear end of the front component 30 is detachably connected to the air intake component 40 and the front end of the inner flow channel component 20, and the water inlet channel 8 is coaxially arranged inside the inner flow channel component 20 and the front component 30; the front end of the tail spray component 50 is detachably connected to the rear end of the air intake component 40; wherein the inner flow channel component 20, the front component 30, the air intake component 40 and the tail spray component 50 are coaxially arranged.

[0029] In some embodiments, the inner flow channel component 20 includes a plurality of groups of non-condensable gas exhaust holes 9, which are evenly arranged on the side wall of the inner flow channel component 20, and each group of non-condensable gas exhaust holes 9 is arranged along the axial direction of the inner flow channel component 20. The aperture of each group of non-condensable gas exhaust holes 9 gradually increases in the direction of seawater flow from the front end to the rear end of the inner flow channel component 20, and the axis of the non-condensable gas exhaust holes 9 and the axis of the water inlet flow channel 8 are at an inclination angle, which is generally within the range of 30° to 60°. The non-condensable gas enters the water inlet flow channel 8 after passing through the non-condensable gas flow channel 6 and the non-condensable gas exhaust holes 9.

[0030] In some embodiments, the air intake assembly 40 further includes a steam supersonic flow channel 7, which is annularly arranged in the side wall of the air intake assembly 40, one end of the steam supersonic flow channel 7 is connected to the steam flow channel 5, and the other end is connected to the tail nozzle assembly 50 from the tail end of the air intake assembly 40. The steam supersonic flow channel 7 of this embodiment adopts a Laval nozzle, which has a flow channel that first contracts and then expands, and can accelerate steam to a supersonic state, which is used to form a condensation shock wave pressurization downstream to achieve a propulsion function.

[0031] In some embodiments, the tail nozzle assembly 50 includes a mixing chamber 12 and a tail nozzle 13; the mixing chamber 12 is arranged at the front of the tail nozzle assembly 50, and the mixing chamber 12 is connected to the steam supersonic flow channel 7; the tail nozzle 13 is arranged at the rear of the tail nozzle assembly 50, and the tail nozzle 13 is a flared structure with a small front and a large rear, and the tail nozzle 13 is coaxially arranged with the mixing chamber 12. The tail nozzle 13 is designed to be in an expanded shape to further realize seawater pressurization and improve propulsion efficiency.

[0032] In some embodiments, the tail nozzle assembly 50 also includes a plurality of water flow exchange holes 11, which are evenly distributed on the outer wall of the mixing chamber 12 of the tail nozzle assembly 50. The design purpose of the water flow exchange holes 11 is to increase the direct contact area between steam and seawater and improve the propulsion effect. The seawater outside the propeller is in direct contact with the internal steam through the water flow exchange holes 11, and the non-condensable gas flowing out of the non-condensable gas exhaust duct 10 is included to achieve flow control and form a stable condensation shock wave. At the same time, in order to prevent steam and non-condensable gas from leaking directly to the outside of the propeller, the water flow exchange holes 11 are designed to be a small hole distribution shape rather than a large area through hole.

[0033] In some embodiments, the two-phase ramjet underwater propulsion system containing non-condensable gas also includes a steam regulating valve 3, which is arranged at the connection between the outlet of the steam regulating valve 3 and the air inlet end of the steam flow channel 5, and the steam flow channel 5 is used to adjust the flow rate of the intake air entering the steam flow channel 5.

[0034] In some embodiments, the two-phase ramjet underwater propulsion system containing non-condensable gas also includes a non-condensable gas regulating valve 4, which is arranged at the connection between the air outlet of the non-condensable gas generating device 2 and the air inlet end of the non-condensable gas flow channel 6, and the non-condensable gas regulating valve 4 is used to adjust the flow rate of the non-condensable gas entering the non-condensable gas flow channel 6.

[0035] In some embodiments, the working principle of the two-phase ramjet underwater propulsion system containing non-condensable gas of the present invention is roughly as follows:

[0036] 1) After passing through the steam regulating valve 3, steam flow channel 5, and steam supersonic flow channel 7, the high-temperature and high-pressure steam is sprayed into the propeller at a supersonic speed (see Figure 2 The white arrows in the figure indicate the direction).

[0037] 2) The non-condensable gas passes through the non-condensable gas regulating valve 4 and the non-condensable gas flow channel 6, and enters the propeller through the non-condensable gas exhaust hole 9 and the non-condensable gas exhaust channel 10 respectively (see Figure 2 The black arrows in the figure indicate the direction).

[0038] 3) Seawater enters the propeller through the water inlet channel 8, and first contacts the non-condensable gas flowing out of the non-condensable gas exhaust hole 9. The non-condensable gas diffuses in the seawater to form microbubbles, which are mainly distributed around the seawater in the water inlet channel 8. The seawater containing the non-condensable gas continues to flow downstream, contacts the supersonic steam, and direct contact condensation of steam-water occurs. Under the regulation of the non-condensable gas, a stable condensation shock wave is formed in the mixing chamber 12, thereby achieving a sudden increase in seawater pressure.

[0039] 4) At the same time, the seawater coming in from the water exchange hole 11 also directly contacts the steam at the inner wall of the propeller, and forms a condensation shock wave under the regulation of the non-condensable gas flowing out from the non-condensable gas exhaust duct 10, further improving the steam supercharging effect.

[0040] 5) After direct contact condensation of steam and water, the steam becomes water and merges into the seawater. The pressurized seawater is further pressurized through the tail nozzle 13 and flows out of the propeller to generate thrust.

[0041] 6) It should be noted that if non-condensable gas is not introduced, only steam is injected into seawater, which can also produce thrust effect. However, due to the violent flow of steam and seawater during the direct contact condensation process, it is difficult to form a stable condensation shock wave during the actual operation of the aircraft, which may affect the stability of the propeller. Therefore, this patent introduces non-condensable gas as a control method, and effectively controls the steam condensation process by adjusting the flow rate of non-condensable gas, thereby forming a stable condensation shock wave during the actual operation and achieving a stable propulsion effect.

[0042] In summary, the two-phase ramjet underwater propulsion system containing non-condensable gas of the present invention has the following advantages: the new two-phase ramjet propulsion device uses steam as a power source, realizes the propulsion function based on the steam-water direct contact condensation pressurization principle, and improves the propulsion efficiency and stability by injecting a trace amount of air. The new two-phase ramjet propulsion device has a complex structure, including complex local structures such as air injection holes, steam nozzles, steam flow channels, air flow channels, and tail nozzles. At the same time, the compact arrangement makes its integrated processing difficult, especially the internal non-condensable gas exhaust holes are difficult to process. Compared with traditional propeller thrusters or water jet thrusters, the two-phase ramjet underwater propulsion system proposed in this patent has a simple structure, no rotating parts, has obvious advantages in anti-cavitation, and can be suitable for high-speed aircraft; the propulsion system proposed in this patent has no rotating parts, bearings and other complex components, and its reliability is also significantly improved, and the large area flow channel structure in the middle is not afraid of large debris in seawater; in addition, for large nuclear-powered aircraft, the propulsion system proposed in this patent can directly utilize the steam generated by nuclear heat, without the need for a complex thermoelectric conversion system in the middle, which can improve the power density of the power system of large nuclear-powered aircraft.

[0043] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A two-phase ramjet underwater propulsion system containing non-condensable gas, characterized in that: include: A two-phase ramjet underwater propulsion system, comprising: An air intake assembly, the front end of which includes a water intake channel; A steam flow channel is arranged on the side wall of the air intake component perpendicular to the axis of the air intake component, and the air outlet end of the steam flow channel is arranged at the rear end of the air intake component; and A non-condensable gas flow channel, which is covered on the periphery of the steam flow channel, and the non-condensable gas enters the water inlet flow channel through the outer wall of the steam flow channel and the inner wall of the non-condensable gas flow channel; a steam generator, the gas outlet of which is in communication with the gas inlet end of the steam flow channel; and The non-condensable gas generating device has a gas outlet connected to the gas inlet end of the non-condensable gas flow channel.

2. The two-phase ramjet underwater propulsion system containing non-condensable gas according to claim 1, characterized in that: The two-phase ramjet underwater thruster also includes: An inner flow channel assembly, which is detachably and coaxially embedded in the central channel of the air intake assembly; A front component, the rear end of which is detachably connected to the air inlet component and the front end of the inner flow channel component, and the water inlet channel is coaxially arranged inside the inner flow channel component and the front component; and A tail spray assembly, the front end of which is detachably connected to the rear end of the air intake assembly; The inner flow channel component, the front component, the air intake component and the tail spray component are coaxially arranged.

3. The two-phase ramjet underwater propulsion system containing non-condensable gas according to claim 2, characterized in that: The inner flow channel component comprises a plurality of groups of non-condensable gas exhaust holes which are evenly arranged in a ring on the side wall of the inner flow channel component, and each group of the non-condensable gas exhaust holes is arranged along the axial direction of the inner flow channel component.

4. The two-phase ramjet underwater propulsion system containing non-condensable gas according to claim 3, characterized in that: The aperture of each group of the non-condensable gas exhaust holes gradually increases from the front end to the rear end of the inner flow channel component, and the axis of the non-condensable gas exhaust holes and the axis of the water inlet flow channel form an inclination angle.

5. The two-phase ramjet underwater propulsion system containing non-condensable gas according to claim 3, characterized in that: The non-condensable gas enters the water inlet flow channel after passing through the non-condensable gas flow channel and the non-condensable gas exhaust hole.

6. The two-phase ramjet underwater propulsion system containing non-condensable gas according to claim 3, characterized in that: The air intake assembly also includes a steam supersonic flow channel, which is arranged in a ring inside the side wall of the air intake assembly. One end of the steam supersonic flow channel is connected to the steam flow channel, and the other end is connected to the tail nozzle assembly from the tail end of the air intake assembly.

7. The two-phase ramjet underwater propulsion system containing non-condensable gas according to claim 6, characterized in that: The tail spray assembly comprises: A mixing chamber, which is arranged at the front part of the tail nozzle assembly, and the mixing chamber is communicated with the steam supersonic flow channel; and The tail nozzle is arranged at the rear of the tail nozzle assembly. The tail nozzle is an expanded structure with a small front and a large rear. The tail nozzle is coaxially arranged with the mixing chamber.

8. The two-phase ramjet underwater propulsion system containing non-condensable gas according to claim 7, characterized in that: The tail spray assembly further comprises a plurality of water flow exchange holes which are evenly distributed and arranged on the outer wall of the mixing chamber of the tail spray assembly.

9. The two-phase ramjet underwater propulsion system containing non-condensable gas according to claim 2, characterized in that: It also includes a steam regulating valve, which is arranged at the connection between the air outlet of the steam regulating valve and the air inlet end of the steam flow channel, and the steam flow channel is used to regulate the flow rate of the intake air entering the steam flow channel.

10. The two-phase ramjet underwater propulsion system containing non-condensable gas according to claim 2, characterized in that: It also includes a non-condensable gas regulating valve, which is arranged at the connection between the gas outlet of the non-condensable gas generating device and the gas inlet end of the non-condensable gas flow channel, and the non-condensable gas regulating valve is used to adjust the flow rate of non-condensable gas entering the non-condensable gas flow channel.

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