Novel hovercraft

Abstract

The utility model discloses a novel hovercraft which comprises a hovercraft body, a hovercraft bottom hovercraft apron and a propelling system. The hull bottom hover apron is arranged on the bottom surface of the hull, and a plurality of lift fans are arranged in the hull; the propelling system is arranged at the tail end of the top of the ship body and comprises an S-shaped air inlet channel and a thrust vector propelling engine. An air inlet of the S-bend air inlet channel is communicated with the external environment, and an air outlet of the S-bend air inlet channel is communicated with an air inlet of the thrust vector propulsion engine; the thrust vectoring propulsion engine comprises an engine body and a thrust vectoring nozzle which is communicated with an exhaust port of the engine body and has a thrust reversing function. Therefore, the jet pipe with the thrust vectoring function is used for replacing a control surface behind a propulsion fan of a traditional hovercraft, the aerodynamic efficiency is high, the response is rapid, and the hovercraft is flexible; and by combining a series of designs such as the S-shaped air inlet channel, exposed parts of the hovercraft are few, and the stealth performance is greatly improved.

Description

Technical Field

[0001] The utility model designs a novel air cushion vehicle, belonging to the technical field of advanced new-concept air cushion vehicles. Background Art

[0002] A hovercraft is a high-speed ship that uses the principle of surface effect to form an air cushion between the hull and the supporting surface (water surface or ground) by relying on air at a pressure higher than atmospheric pressure, so that the hull can sail completely or partially away from the supporting surface. According to the way the air cushion is generated, it can be divided into two types: full-cushion hovercraft and sidewall hovercraft. Common hovercraft are equipped with engines represented by piston engines or gas turbines, which are used to generate air cushions and drive the hovercraft forward. The high-pressure air generated by the piston engine or gas turbine is sent into the air chamber of the bottom cavity of the ship through a pipe to form an air cushion to hold up the hull, and the engine drives the propeller (mostly a propulsion fan) to make the hovercraft sail close to the supporting surface. The speed of the hovercraft is as high as 60~80km / h, and its resistance when sailing at high speed is the limit that affects its further speed increase.

[0003] Looking at the current hovercraft, its ability to sail at high speed close to the water surface while taking into account a large load is the most important advantage that attracts attention. Therefore, hovercraft is often used in scenarios where the load needs to be delivered quickly, such as material transportation, beach landing, etc. However, many disadvantages of hovercraft have also become factors that restrict its development. Among the many disadvantages, the first is the fuzzy attitude control when sailing at high speed. Since the hovercraft floats on the support surface, the support surface has a weak effect on the hovercraft; coupled with the heavy weight and inertia of the hovercraft, the common method of using the propeller to blow the rudder surface is difficult to achieve its agile turning. Secondly, after the hovercraft lands on the beach, it is difficult to retreat quickly on a narrow beach. The common way for the hovercraft to retreat is to turn around by blowing the rudder surface with the propeller to complete the retreat; or to achieve retreat by changing the pitch of the propulsion fan to generate reverse thrust. However, the above two methods have different disadvantages: turning around is difficult and time-consuming, and the variable pitch method can certainly generate reverse thrust, but because the fan blades are working at a non-design point after the pitch is changed, the efficiency is low, the reverse thrust is limited, and the retreat speed is slow. Of course, for possible practical applications, further improving the load capacity and reducing resistance, considering possible military scenarios, and improving its stealth capability through comprehensive design are also urgent needs for the future design and use of hovercraft. Utility Model Content

[0004] Purpose of the utility model: In order to overcome the deficiencies in the prior art, the utility model describes a new type of hovercraft, which, based on the working principle of a traditional hovercraft, uses a thrust vector propulsion engine with a reverse thrust function to generate a heading control capability and a reverse thrust function for rapid retreat for the hovercraft.

[0005] Technical solution: To achieve the above purpose, the technical solution adopted by the utility model is:

[0006] A novel hovercraft comprises a hull, a bottom air cushion skirt and a propulsion system; the bottom air cushion skirt is arranged on the bottom surface of the hull, and a plurality of lift fans are arranged inside the hull; the propulsion system is arranged at the tail end of the top of the hull, and comprises an S-bend air inlet and a thrust vector propulsion engine; the air inlet of the S-bend air inlet is connected to the external environment, and the air outlet of the S-bend air inlet is connected to the air inlet of the thrust vector propulsion engine; the thrust vector propulsion engine comprises an engine body and a thrust vector nozzle with reverse thrust function which is connected to the exhaust port of the engine body.

[0007] Preferably, the lower edge of the air inlet of the S-curve air inlet is higher than the upper edge of the thrust vectoring engine in the vertical direction, and at the same time, the upper edge of the air inlet of the S-curve air inlet is lower than the highest point of the lift-enhancing surface in the vertical direction.

[0008] Preferably, the thrust vector nozzle with reverse thrust function is a binary mechanical thrust vector nozzle with reverse thrust function or an aerodynamic thrust vector nozzle with reverse thrust function.

[0009] Preferably, the engine body is a turbofan engine, a turbojet engine, a gas turbine driven fan or a piston engine driven fan.

[0010] Preferably, the four sides of the hull are connected to the air cushion skirt of the bottom of the ship through inclined hull side walls, and two lift-enhancing profiles are symmetrically arranged on both sides of the top of the hull along the length extension direction of the hull; the area of ​​the hull between the two lift-enhancing profiles is the deck, and a front ramp is arranged at the front end of the deck, and a rear ramp is arranged at the rear end of the deck;

[0011] There are two sets of propulsion systems, which are connected to the tail ends of the two lift-enhancing surfaces in a one-to-one correspondence.

[0012] Preferably, the center line of the single-sided S-bend air inlet is inclined from the vicinity of the center of the hovercraft to both sides, and the air inlet and the air outlet of the S-bend air inlet are offset in both the horizontal and vertical directions.

[0013] Preferably, the lift-enhancing profile is formed by increasing the profile angle of attack based on the typical asymmetric low-speed wing airfoil profile, and the increased profile angle of attack is 2°-5°.

[0014] Preferably, an inlet of a lift fan is arranged at the location of the S-curve air inlet; the air inlet area of ​​the S-curve air inlet is larger than the sum of the inlet areas of the thrust vector propulsion engine and the single lift fan.

[0015] Preferably, the air inlet area of ​​the S-curve inlet duct should be 130%-170% of the sum of the inlet areas of the thrust vector propulsion engine and the single lift fan.

[0016] Preferably, the angle between the initial position of the lift-enhancing profile on the top of the hull and the horizontal direction is α, the angle between the front ramp and the horizontal plane is β, α+β≤70°, β≤60°, and α≤20°.

[0017] Beneficial effects: Compared with the prior art, it has the following advantages:

[0018] (1) The utility model uses a nozzle with thrust vectoring function to replace the rudder behind the propulsion fan of the traditional hovercraft, which has high aerodynamic efficiency, rapid response, and flexible maneuverability. Combined with a series of designs such as the S-bend air inlet, the hovercraft has fewer exposed parts and greatly improved stealth performance.

[0019] (2) The utility model uses a thrust vector nozzle with reverse thrust function to replace the traditional hovercraft's variable pitch reverse propeller or on-site differential U-turn reversing method, which allows for rapid retreat and can further accurately control the reversing direction by controlling the nozzle, thus providing high safety in use;

[0020] (3) The comprehensive use of inclined walls, S-curved air inlets, etc. greatly improves the stealth of the hovercraft, reduces the probability of being discovered, and improves battlefield survivability.

[0021] Therefore, the new hovercraft provided by the utility model, based on the working principle of the traditional hovercraft, generates the reverse thrust function for the hovercraft through the thrust vector propulsion engine with reverse thrust function, and generates the heading control capability and rapid retreat reverse thrust function for the hovercraft; through the specially designed lift-enhancing surface on the hull, combined with the suction effect of the downstream air inlet and the engine, the hovercraft can achieve high-efficiency low-resistance navigation and load capacity improvement; by setting an S-bend air inlet in front of the thrust vector propulsion engine, burying part of the lift fan air inlet in the S-bend air inlet, and the inclined hull side wall, the radar reflection cross-sectional area in all directions of the hovercraft is reduced, and the stealth function is achieved. Through the above design, the stealth, maneuverability and carrying capacity of the hovercraft are comprehensively improved, meeting the needs of the future military scene for a new generation of hovercraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is the main view of a new type of hovercraft;

[0023] Figure 2 This is a top view of the AA section of a new type of hovercraft;

[0024] Figure 3 This is a top view of a new type of hovercraft;

[0025] Figure 4 This is the front view of the BB section of a new type of hovercraft;

[0026] Figure 5 This is a top-down perspective view of a new type of hovercraft;

[0027] Figure 6 The figure is a comparison of the numerical simulation flow field calculation of the typical configuration of the conventional hovercraft and the utility model, wherein: (a) represents the numerical simulation velocity cloud diagram of the symmetry plane of the conventional hovercraft; (b) represents the numerical simulation velocity cloud diagram of the symmetry plane of the stealth hovercraft described in the utility model;

[0028] Figure 7 It is a partial schematic diagram of the head of the new hovercraft;

[0029] In the figure, it includes: 1. air cushion skirt at the bottom of the ship, 2. hull, 3. propulsion system;

[0030] Among them: 2.1, front springboard, 2.2, deck, 2.3, lift fan, 2.4, rear springboard, 2.5, lift-enhancing surface; 3.1, thrust vectoring engine, 3.2, S-curve inlet. DETAILED DESCRIPTION

[0031] The utility model will be further described below in conjunction with the accompanying drawings and embodiments.

[0032] like Figures 1 to 5 As shown, the novel hovercraft described in the utility model mainly includes a bottom air cushion skirt 1, a hull 2 ​​and a propulsion system 3.

[0033] The top of the hull 2 ​​is raised above the bottom air cushion skirt 1 through four sides. A lift-enhancing surface 2.5 is arranged on the top of the hull 2, and the four sides are all inclined hull side walls, corresponding to the front side wall of the hull, the rear side wall of the hull, the left side wall of the hull and the right side wall of the hull. A front ramp 2.1 is arranged on the front side wall of the hull, and a rear ramp 2.4 is arranged on the rear side wall of the hull. Loads such as vehicles can enter the interior of the hovercraft through the front and rear ramps 2.4 and be moored on the deck 2.2. Several lift fans 2.3 are also arranged inside the hull 2 ​​to draw air from the top of the hovercraft to the bottom air cushion skirt 1 of the hull, and blow it out from the lower part of the bottom air cushion skirt 1 of the hull, so that the hovercraft can float on the water surface, lawn, mud, etc.; the principle of the lift fan 2.3 is consistent with that of traditional active hovercraft, and the common number is 4-8.

[0034] A propulsion system 3 is arranged near the top tail end of the hull 2, and the propulsion system 3 is composed of an S-bend air inlet 3.2, a thrust vector propulsion engine 3.1 and its accessories. The S-bend air inlet 3.2 realizes air intake from the outside and efficiently transports it to the thrust vector propulsion engine 3.1; preferably, there are two sets of propulsion systems 3, which are symmetrically arranged on the left and right sides of the hovercraft. The core power source of the thrust vector propulsion engine 3.1 is a turbofan engine, a turbojet engine, or a fan driven by a gas turbine, or a fan driven by a piston engine. The high-speed jet at the outlet of the turbofan engine or turbojet engine or the high-speed jet downstream of the fan enters the thrust vector nozzle with reverse thrust function, which can generate thrust vector and reverse thrust function by changing the direction of the airflow; the nozzle can be a binary mechanical thrust vector nozzle with reverse thrust function, or it can be an aerodynamic thrust vector nozzle with reverse thrust function (such as a bypass passive double-throat vector nozzle with reverse thrust function, ZL 201510140955.1). When sailing forward at high speed, the nozzle can deflect the airflow to the left, right, or not deflect it, which is used for the hovercraft's heading control and to reduce the hovercraft's attitude control ambiguity caused by inertia. After the beach landing is completed, the thrust vector nozzle can be adjusted to the reverse thrust function, and the airflow is ejected obliquely forward along the left and right sides of the thrust vector propulsion engine 3.1, which is used for high-speed reversing and rapid retreat, avoiding the traditional hovercraft from staying in the war zone for a long time during the most dangerous time of beach landing.

[0035] In order to achieve a better stealth effect, the present invention requires that the four sides of the hull 2 ​​are inclined hull side walls respectively, and also has certain requirements for the S-curved air inlet 3.2, at least to meet the requirement that in the vertical direction, the lower edge of the inlet of the S-curved air inlet 3.2 is higher than the upper edge of the thrust vector propulsion engine 3.1; preferably, in addition to meeting the aforementioned geometric constraints, it is also necessary to meet the requirement that in the vertical direction, the upper edge of the inlet of the S-curved air inlet 3.2 is lower than the highest point of the lift-enhancing surface 2.5 on the top of the hull 2.

[0036] Furthermore, considering the overall layout and design of the utility model, the inlet of the partial lift fan 2.3 should be arranged in the S-bend air inlet 3.2, that is, the partial lift fan 2.3 should share the S-bend air inlet 3.2 with the thrust vectoring engine 3.1.

[0037] Furthermore, the top of the hull 2 ​​is a lift-enhancing surface 2.5, which is a special surface designed using boundary layer suction technology. Its downstream is connected to the inlet of the S-bend air inlet 3.2. Through the suction effect of the thrust vectoring propulsion engine 3.1, the flow separation of the airflow when flowing on the lift-enhancing surface 2.5 is reduced, and at the same time, the boundary layer thickness and the flow resistance of the airflow are expected to be reduced; further, through the suction effect of the thrust vectoring propulsion engine 3.1, the atmospheric pressure acting on the lift-enhancing surface 2.5 is reduced, thereby achieving an improvement in the load capacity of the hovercraft. The optimized configuration is expected to increase the maximum load capacity of the hovercraft by more than 5% and reduce the maximum drag by more than 10%.

[0038] Furthermore, in order to improve the aerodynamic performance of the hovercraft, the design of the S-bend air inlet 3.2 should be considered together with the design of the lift-enhancing profile 2.5 and the inlet of the lift fan 2.3. The optimal design is that the inlet width of the S-bend air inlet 3.2 is completely consistent with the width of the lift-enhancing profile 2.5, that is, the center line of the single-side S-bend air inlet 3.2 should be deflected from the vicinity of the center of the hovercraft to both sides, and its inlet and outlet are offset in both the horizontal and vertical directions.

[0039] Furthermore, the design of the lift-enhancing profile 2.5 can be based on the typical asymmetric low-speed wing airfoil profile, select its upper surface, appropriately increase the profile angle of attack by 2°-5°, and carry out the overall design of the hovercraft; then combine the S-bend air inlet 3.2, the lift fan 2.3 air intake and other aspects to carry out three-dimensional multi-objective multi-variable comprehensive design and optimization. The typical airfoil profile that can be selected is the wing airfoil that meets the use of about 30m / s, such as NACA 4418.

[0040] Furthermore, the design of the hovercraft must take into account the need for high-speed forward sailing and rapid reverse travel. Therefore, from the rear of the hovercraft, the two thrust vector propulsion engines 3.1 are arranged high on the left and right sides of the hovercraft, sharing a reverse thrust airflow channel in the middle, presenting a "concave" shape, to meet the requirement of minimizing the negative interference of the reverse thrust airflow when rapidly reversing.

[0041] Figure 6 The figure is a comparison of the numerical simulation flow field calculation of the typical configuration of the conventional hovercraft and the utility model, and shows the numerical simulation velocity cloud diagram of the symmetry plane. Among them: (a) shows the numerical simulation velocity cloud diagram of the symmetry plane of the conventional hovercraft; (b) shows the numerical simulation velocity cloud diagram of the symmetry plane of the stealth hovercraft described in the utility model; by comparing the two, it can be seen that the flow field of the utility model is more uniform and the separation zone is smaller.

[0042] Considering the actual use of the utility model, the inlet flow of the S-bend air inlet 3.2 needs to meet the needs of the propulsion system 3 and a set of lift fans 2.3 for air flow. Considering that the actual working speed of the utility model is 60-100km / h, and the various losses caused by the flow, generally, the inlet area of ​​the S-bend air inlet 3.2 should be larger than the sum of the inlet areas of the thrust vector propulsion engine 3.1 and the single lift fan 2.3 to meet the needs of flow conservation. Preferably, the inlet area of ​​the S-bend air inlet 3.2 should be 130%-170% of the inlet area of ​​the thrust vector propulsion engine 3.1 and the single lift fan 2.3.

[0043] From the perspective of the optimal aerodynamic performance and stealth performance of the utility model, the bow of the hovercraft described in the utility model should be as sharp as possible; however, a too sharp bow will change the weight distribution of the hovercraft, affecting the control and normal navigation. Therefore, there is a better range of values ​​for the angle of the head of the hovercraft. Let the initial position of the top lift profile 2.5 of the hovercraft hull 2 ​​be at an angle α to the horizontal direction, and the bow of the hovercraft (front ramp 2.1) be at an angle β to the horizontal plane. Generally, the sum of the above two angles should be less than 90°. Preferably, the above two angles should meet a certain range, α+β≤70° and β≤60° and α≤20°.

[0044] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A new type of hovercraft, comprising a hull, a bottom air cushion skirt and a propulsion system; the bottom air cushion skirt is arranged on the bottom surface of the hull, and a plurality of lift fans are arranged inside the hull; the characteristics are: The propulsion system is arranged at the tail end of the top of the hull, and includes an S-curve air inlet and a thrust vector propulsion engine; the air inlet of the S-curve air inlet is connected to the external environment, and the air outlet of the S-curve air inlet is connected to the air inlet of the thrust vector propulsion engine; the thrust vector propulsion engine includes an engine body and a thrust vector nozzle with reverse thrust function connected to the exhaust port of the engine body.

2. The new hovercraft according to claim 1 is characterized in that: The lower edge of the air inlet of the S-curve air inlet is higher than the upper edge of the thrust vectoring engine in the vertical direction. At the same time, the upper edge of the air inlet of the S-curve air inlet is lower than the highest point of the lift-enhancing surface in the vertical direction.

3. The new hovercraft according to claim 2 is characterized in that: The thrust vector nozzle with reverse thrust function is a binary mechanical thrust vector nozzle with reverse thrust function or an aerodynamic thrust vector nozzle with reverse thrust function.

4. The new hovercraft according to claim 3 is characterized in that: The engine body is a turbofan engine, a turbojet engine, a fan driven by a gas turbine or a fan driven by a piston engine.

5. The new hovercraft according to claim 4 is characterized in that: The four sides of the hull are connected to the air cushion skirt at the bottom of the ship through the inclined side wall surface of the hull, and two lift-enhancing surfaces are symmetrically arranged on both sides of the top of the hull along the length extension direction of the hull; the area of ​​the hull between the two lift-enhancing surfaces is the deck, and the front end of the deck is arranged with a front ramp, and the rear end of the deck is arranged with a rear ramp; There are two sets of propulsion systems, which are connected to the tail ends of the two lift-enhancing surfaces in a one-to-one correspondence.

6. The new hovercraft according to claim 5 is characterized in that: The centerline of the single-sided S-curve air inlet is tilted from the center of the hovercraft to both sides, and the air inlet and outlet of the S-curve air inlet are offset in the horizontal and vertical directions.

7. The new hovercraft according to claim 6, characterized in that: The lift-enhancing profile is formed by increasing the profile angle of attack of a typical asymmetric low-speed wing airfoil profile, and the increased profile angle of attack is 2°-5°.

8. The new hovercraft according to claim 7, characterized in that: The inlet of a lift fan is arranged at the location of the S-curve air inlet; the air inlet area of ​​the S-curve air inlet is larger than the sum of the inlet areas of the thrust vector propulsion engine and a single lift fan.

9. The new hovercraft according to claim 8, characterized in that: The air inlet area of ​​the S-curve inlet should be 130%-170% of the sum of the inlet areas of the thrust vector propulsion engine and a single lift fan.

10. The new hovercraft according to claim 9, characterized in that: The initial position of the lift-enhancing surface on the top of the hull has an angle α with the horizontal direction, the angle between the front ramp and the horizontal plane is β, α+β≤70°, β≤60°, and α≤20°.

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