Adsorption tank body, ventilation system for methanol fuel aircraft and aircraft

Abstract

The invention belongs to the technical field of aircraft fuel system design, and discloses an adsorption tank, a ventilation system for a methanol fuel aircraft and the aircraft. The adsorption tank comprises: a carbon tank housing for accommodating an adsorbent; the desorption nozzle assembly is a U-shaped shell with an opening in the upper surface and is communicated with the lower end of the carbon tank shell; the atmosphere mouthpiece is connected with the upper end of the carbon tank shell; the adsorption mouthpiece is connected with the middle part of the lower end of the carbon tank shell and is surrounded by the desorption mouthpiece assembly; filter plates and porous metal plates are arranged at the upper end and the lower end in the carbon tank shell from inside to outside; an adsorbent is filled between the filter plates at the upper and lower ends; a spring is arranged between the porous metal plate at the upper end and the upper panel of the carbon tank and is used for pressing the adsorbent; the carbon tank is provided with a middle filter plate for dividing the adsorbent filling area into an upper subarea and a lower subarea; the upper partition is filled with zeolite molecular sieves, and the lower partition is filled with carbon powder.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft fuel system design, and discloses an adsorption tank, a ventilation system for a methanol-fueled aircraft, and an aircraft. Background Art

[0002] With the rapid development of the global electric vehicle industry, relevant professional technologies have migrated to the aviation field. eVTOL (electric vertical takeoff and landing aircraft) has the advantages of high safety, low operating cost, low noise, etc., and has great prospects for becoming an "air taxi". However, due to the fact that the battery energy density is much lower than that of liquid fuel for a long time, and the energy density requirement for the energy system of vertical takeoff and landing aircraft is much higher than that of electric vehicles, hybrid power will remain the mainstream power form of eVTOL for a long time.

[0003] As a new type of energy, methanol has the advantages of low cost, low combustion pollution (the PM2.5 emission is 80% - 85% less than that of gasoline and diesel, and the nitrogen oxide emission is 60% - 80% less), and being renewable, etc., and has the potential to become the mainstream fuel for low-altitude aircraft such as hybrid eVTOL. However, methanol has certain volatility and toxicity. Methanol evaporation in the methanol fuel tank of the aircraft is released into the atmosphere through the ventilation system, which will cause environmental pollution.

[0004] Such as Patent CN200810024831 and Patent CN201922478656, in the automotive field, the problem of methanol evaporation environmental pollution is basically solved by the same means as the fuel evaporation control system. However, generally, the fuel consumption rate of aircraft is much larger than that of cars, the fuel tanks are more, the ventilation system is more complex, and the requirement for the ventilation reliability of the fuel tank (affecting the engine fuel supply safety) is higher. Methanol fuel has been used on a large scale in the automotive field, but it is rarely used in the aviation field. It is necessary to solve the problem of methanol evaporation environmental pollution in combination with the technical characteristics of the aircraft and ensure the reliable ventilation of the methanol fuel tank. Summary of the Invention

[0005] Object of the Invention: To provide a methanol adsorption tank body, a ventilation system for a methanol-fueled aircraft, and an aircraft, which are used to prevent methanol vapor from leaking to the outside of the aircraft through the ventilation system, achieve efficient adsorption and desorption of methanol vapor, and ensure the reliable ventilation of the methanol fuel tank.

[0006] Technical Solution: A methanol adsorption tank body, comprising: An adsorption tank shell for accommodating an adsorbent; An atmosphere nozzle assembly connected to the upper end of the adsorption tank shell; The desorption nozzle assembly is a U-shaped shell with an open upper surface and is connected to the lower end of the adsorption tank shell; The adsorption nozzle assembly is connected to the lower end of the adsorption tank shell; The adsorption tank shell has filter plates and porous metal plates installed at both the top and bottom ends from the inside out. An adsorbent is filled between the upper and lower filter plates; A spring is provided between the porous metal plate at the top and the top panel of the adsorption tank to compress the adsorbent; The adsorption tank is equipped with an intermediate filter plate that divides the adsorbent filling area into upper and lower sections.

[0007] The methanol adsorption tank adopts a top-suction design, with the atmospheric inlet assembly located at the top of the adsorption tank, and the adsorption and desorption inlet assemblies located at the bottom. Because methanol vapor is denser than air, the top-suction design provides better adsorption. It also prevents methanol vapor condensation in the methanol fuel tank hose from entering the adsorption tank and reducing adsorbent failure. The adsorption inlet assembly has multiple inlets, allowing it to simultaneously adsorb methanol vapor overflowing from multiple methanol fuel tank vent pipes, significantly reducing weight compared to using multiple adsorption tanks.

[0008] Furthermore, the adsorption nozzle assembly is partially surrounded by the desorption nozzle assembly, which facilitates the arrangement of the methanol fuel tank hose on the side wall of the engine body and also allows for more thorough desorption of the methanol adsorbed by the carbon powder on the upper part of the adsorption nozzle assembly.

[0009] Furthermore, the upper section is filled with zeolite molecular sieve powder material, and the lower section is filled with carbon powder. The carbon powder in the lower activated carbon chamber is made of alkaline modified wood-based activated carbon or other activated carbon with a large methanol adsorption capacity, reducing the amount of activated carbon used and lowering the volume and weight of the adsorption tank. The zeolite molecular sieve in the upper zeolite molecular sieve chamber is made of low-silicon ZSM-5 or other zeolite molecular sieves with a large water adsorption capacity and easy desorption. When the engine consumes methanol, the fuel tank replenishes air, and the adsorption ventilation system draws in water vapor from the air, reducing the amount of water vapor entering the carbon powder chamber and reducing the degree of decrease in methanol adsorption capacity of the carbon powder due to water absorption.

[0010] Furthermore, multiple small gear-shaped air venting strips are installed between the upper and lower filter plates. These strips pass through the middle filter plate and have a gear-shaped cross-section. The irregular shape of the small gear-shaped air venting strips forms multiple narrow ventilation channels with the adsorbent, ensuring the fuel tank replenishment needs when the engine consumes methanol for short periods, even if the adsorbent fails or the bypass fails.

[0011] Furthermore, a U-shaped baffle is provided at the bottom of the adsorption tank. The height of the U-shaped baffle is 1 / 4 to 1 / 2 of the height of the lower partition. It is used to separate the connecting areas of the adsorption nozzle and the desorption nozzle assembly, so as to avoid the adsorption port and the desorption port having too small a flow resistance, which would cause the adsorption port to suck into the methanol fuel tank connected to the desorption port, resulting in excessive negative pressure in the methanol fuel tank and making it difficult to supply methanol fuel to the engine.

[0012] A ventilation system for a methanol-fueled aircraft, the ventilation system comprising: Methanol adsorption tank; The atmospheric inlet assembly is connected to the ventilation connector assembly via an atmospheric hose. The ventilation connector assembly includes a ventilation hood, a ventilation mesh, and a ventilation elbow. The ventilation connector is located on the side of the machine body. The ventilation hood is used to significantly reduce the entry of rainwater and other external impurities into the ventilation system. The ventilation mesh is used to prevent large impurities such as leaves from drifting into the ventilation system. The upward-pointing ventilation elbow ensures that most of the water that enters (such as the washing water that enters at certain angles during machine body washing) flows out of the machine body and avoids entering the ventilation system. The adsorption nozzle assembly is connected to the venting float valve via a methanol fuel tank hose. The venting float valve is located on the methanol fuel tank to prevent liquid methanol from entering the adsorption tank through the methanol fuel tank hose and causing adsorbent failure. The desorption nozzle assembly is connected to the engine intake manifold via an engine hose. The atmospheric inlet assembly of the adsorption tank is connected to the desorption inlet assembly via a bypass pipeline; The adsorption tank is equipped with a temperature sensor and an externally wrapped heating element.

[0013] When the engine is stopped or the methanol fuel tank is being refueled, methanol vapor in the methanol fuel tank overflows through the methanol fuel tank pipe and is adsorbed by the activated carbon in the adsorption tank. When the engine is running, the methanol vapor stored in the adsorption tank is carried by fresh air entering through the vent and is injected into the engine intake manifold through the engine hose, where it enters the engine for combustion. At the same time, when the engine consumes methanol, the fresh air entering through the vent is filtered through the entire adsorption tank to replenish the fuel tank.

[0014] Furthermore, a one-way valve is installed in the bypass pipeline. The one-way valve allows flow from the atmospheric inlet to the desorption inlet assembly. When the adsorbent fails and the flow resistance increases, the one-way valve opens, allowing fresh outside air to flow to the engine intake manifold through the bypass pipeline without passing through the adsorption tank. This prevents excessive flow resistance in the adsorption tank from causing the adsorption port to draw into the methanol fuel tank connected to the desorption port, resulting in excessive negative pressure in the methanol fuel tank and difficulty in supplying methanol fuel to the engine. At the same time, when the engine consumes methanol, the fresh air entering through the vent can replenish the fuel tank through the bypass pipeline and the lower activated carbon chamber. Furthermore, the check valve is connected to an alarm device. When the check valve is opened, the alarm device issues a blockage alarm message for the adsorption tank.

[0015] Furthermore, the heating components are not activated when the engine is not running. Since methanol has a stronger adsorption capacity for carbon powder than gasoline, and the aircraft consumes a lot of fuel and requires a large ventilation capacity, resulting in a large amount of methanol vapor adsorption, the heating components are controlled to heat the adsorption tank to the rated temperature when the engine is running, thereby promoting methanol desorption.

[0016] Furthermore, the flow area of ​​the engine hose is Q1, the total flow area of ​​the methanol fuel tank hose is Q2, and the flow area of ​​the atmospheric hose is Q3. Q3 = Q1 ≥ 2Q2.

[0017] Since the desorption flow rate of the engine intake system is an order of magnitude larger than the exhaust flow rate of the fuel tank when refueling, and the exhaust flow rate of the fuel tank when refueling is an order of magnitude larger than the fuel tank replenishment flow rate when the engine consumes methanol, the ventilation requirements of the fuel tank exhaust when refueling and the fuel tank replenishment when the engine consumes methanol can be fully met when there is no adsorption tank blockage alarm.

[0018] An aircraft includes the aforementioned ventilation system, wherein a multi-engine aircraft has one set of the aforementioned ventilation system on each side of the fuselage, which can further improve the ventilation reliability of the methanol fuel tank.

[0019] In summary, the beneficial effects of the present invention are as follows: This invention provides a methanol adsorption tank and a ventilation system and aircraft for methanol-fueled aircraft, which can prevent methanol vapor from leaking to the outside of the aircraft through the ventilation system, achieve efficient adsorption and desorption of methanol vapor, and ensure reliable ventilation of the methanol fuel tank. Attached Figure Description

[0020] Figure 1 : A schematic diagram of an adsorption tank; Figure 2 : A schematic diagram of a ventilation system for a methanol-fueled aircraft; Figure 3 Schematic diagram of a pinion air vent strip; 1. Vent connector assembly; 2. Atmospheric hose; 3. Adsorption tank assembly; 4. Heating assembly; 5. Temperature sensor; 6. Bypass pipeline assembly; 7. Engine hose; 8. Methanol fuel tank hose; 9. Vent float valve; 10. Engine intake manifold; 1.1 Vent hood; 1.2 Vent mesh; 1.3 Vent elbow; 3.1 Adsorption tank shell; 3.2 Atmospheric connector assembly; 3.2.1 Atmospheric connector; 3.2.2 Bypass connector 1; 3.3 Filter plate, 3.4 spring, 3.5 porous metal plate, 3.6 zeolite molecular sieve cavity, 3.7 intermediate filter plate, 3.8 activated carbon cavity, 3.9 pinion air venting strip, 3.10 partition, 3.11 adsorption nozzle assembly, 3.11.1 adsorption nozzle, 3.12 desorption nozzle assembly, 3.12.1 desorption nozzle, 3.12.2 bypass nozzle 2; 6.1 one-way valve, 6.2 alarm device, 6.3 bypass pipe. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be reviewed and described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Example 1: An embodiment of a methanol adsorption tank Figure 1 As shown, a methanol adsorption tank includes: an adsorption tank shell 3.1 for containing adsorbent; an atmospheric inlet assembly 3.2 connected to the upper end of the adsorption tank shell; a desorption inlet assembly 3.12, which is a U-shaped shell with an open upper surface and communicates with the lower end of the adsorption tank shell; an adsorption inlet assembly 3.11 connected to the lower end of the adsorption tank shell; filter plates 3.3 and porous metal plates 3.5 are provided at both the upper and lower ends of the adsorption tank shell from the inside out; adsorbent is filled between the filter plates at the upper and lower ends; a spring 3.4 is provided between the porous metal plate 3.5 at the upper end and the upper panel of the adsorption tank to compress the adsorbent; the adsorption tank has an intermediate filter plate 3.7 that divides the adsorbent filling area into upper and lower partitions. The methanol adsorption tank adopts a top-suction type, with the atmospheric inlet assembly 3.2 at the top of the adsorption tank, and the adsorption inlet assembly 3.11 and desorption inlet assembly 3.12 at the bottom of the adsorption tank. The adsorption inlet assembly 3.11 is equipped with multiple adsorption inlets 3.11.1, which can simultaneously adsorb methanol vapor overflowing from multiple methanol fuel tank vent pipes.

[0023] The adsorption nozzle assembly 3.11 is partially surrounded by the desorption nozzle assembly 3.12.

[0024] The upper section is filled with zeolite molecular sieve powder material, and the lower section is filled with carbon powder. The carbon powder in the lower activated carbon chamber 3.8 is alkaline modified wood-based activated carbon or other activated carbon with a large methanol adsorption capacity. The zeolite molecular sieve in the upper zeolite molecular sieve chamber 3.6 is low-silicon ZSM-5 or other zeolite molecular sieve with a large water adsorption capacity and easy desorption.

[0025] Multiple small gear air venting strips 3.9 are provided between the upper and lower filter plates. The small gear air venting strips 3.9 pass through the middle filter plate 3.7 and have a gear-shaped cross-section.

[0026] A U-shaped baffle 3.10 is provided at the bottom of the adsorption tank. The height of the U-shaped baffle is 1 / 4 to 1 / 2 of the height of the lower section.

[0027] Example 2: A ventilation system for methanol-fueled aircraft, such as Figure 2As shown, a ventilation system for a methanol-fueled aircraft includes: a methanol adsorption tank 3; an atmospheric inlet assembly 3.2 connected to a ventilation connector assembly 1 via an atmospheric hose 2; the ventilation connector assembly includes a ventilation hood 1.1, a ventilation net 1.2, and a ventilation elbow 1.3, and the ventilation connector is located on the side of the fuselage; an adsorption inlet assembly 3.11 connected to a ventilation float valve 9 via a methanol fuel tank hose 8, the ventilation float valve being mounted on the methanol fuel tank; a desorption inlet assembly 3.12 connected to an engine air intake duct 10 via an engine hose 7; the atmospheric inlet assembly 3.2 of the adsorption tank is connected to the desorption inlet assembly 3.12 via a bypass pipe 6; the adsorption tank is equipped with a temperature sensor 5 and an externally wrapped heating assembly 4.

[0028] When the engine is stopped or the methanol fuel tank is being refueled, methanol vapor in the methanol fuel tank overflows through the methanol fuel tank pipe 8 and is adsorbed by the activated carbon in the adsorption tank 3. When the engine is running, the methanol vapor stored in the adsorption tank 3 is carried by the fresh air entering through the vent 1 and is injected into the engine intake manifold 10 through the engine hose 7, and enters the engine for combustion along with the engine intake air. At the same time, when the engine consumes methanol, the fresh air entering through the vent is filtered through the entire adsorption tank 3 to replenish the fuel tank.

[0029] The flow area of ​​the engine hose 7 is Q1, the total flow area of ​​the methanol fuel tank hose 8 is Q2, and the flow area of ​​the atmosphere hose 7 is Q3. Q3 = Q1 ≥ 2Q2.

[0030] When the engine is not running, the heating component 4 is not working; when the engine is running, the heating component 4 is controlled to heat the adsorption tank to the rated temperature to promote methanol desorption.

[0031] Example 3: A ventilation system for methanol-fueled aircraft, such as Figure 2 As shown, a one-way valve 6.1 is installed in the bypass pipe 6. The one-way valve 6.1 allows the flow direction to be from the atmospheric inlet assembly 3.2 to the desorption inlet assembly 3.12. When the adsorbent fails and the flow resistance increases, the one-way valve 3.1 opens, and fresh air from the outside flows to the engine through the bypass pipe 6 without passing through the adsorption tank 3. This avoids the adsorption port drawing into the methanol fuel tank connected to the desorption port due to excessive flow resistance in the adsorption tank 3, which would cause excessive negative pressure in the methanol fuel tank and make it difficult to supply methanol fuel to the engine. At the same time, when the engine consumes methanol, the fresh air entering through the vent can replenish the fuel tank through the bypass pipe 6 and the lower activated carbon chamber 3.8. The one-way valve 6.1 is connected to the alarm device 6.2. When the one-way valve 6.1 is open, the alarm device 6.2 issues an adsorption tank blockage alarm message.

[0032] Example 4: A ventilation system for methanol-fueled aircraft, such as Figure 3As shown, the cross-section of the gear-shaped venting strip 3.9 inside the adsorption tank 3 is gear-shaped, forming multiple narrow ventilation channels with the adsorbent. In the event of adsorbent failure and bypass failure, the fuel tank is guaranteed to replenish gas when the engine consumes methanol for a short period of time.

[0033] Example 5: An aircraft including the aforementioned ventilation system, wherein a multi-engine aircraft has one set of the aforementioned ventilation system on each side of the fuselage, which can further improve the ventilation reliability of the methanol fuel tank.

Claims

1. An adsorption tank, characterized in that, include: The carbon canister shell is used to contain the adsorbent; The desorption nozzle assembly is a U-shaped housing with an opening on the upper surface, which is connected to the lower end of the carbon canister housing; The atmospheric nozzle is connected to the upper end of the carbon canister shell; The adsorption nozzle is connected to the lower middle part of the carbon canister shell and is surrounded by the desorption nozzle assembly; The carbon canister shell has filter plates and porous metal plates installed at both the top and bottom ends from the inside out. An adsorbent is filled between the upper and lower filter plates; A spring is provided between the porous metal plate at the top and the top panel of the carbon canister to compress the adsorbent; The carbon canister is equipped with an intermediate filter plate that divides the adsorbent filling area into upper and lower sections; the upper section is filled with zeolite molecular sieves, and the lower section is filled with carbon powder.

2. The adsorption tank according to claim 1, characterized in that, The atmospheric nozzle is connected to the desorption nozzle assembly via a bypass line.

3. The adsorption tank according to claim 2, characterized in that, The bypass line is equipped with a check valve, which allows the flow direction to be from the desorption nozzle assembly to the atmospheric nozzle.

4. The adsorption tank according to claim 3, characterized in that, The check valve is equipped with an alarm, which pops up an alarm sign when the check valve is opened.

5. The adsorption tank according to claim 1, characterized in that, Multiple small gear-shaped air-venting strips are installed between the upper and lower filter plates. The small gear-shaped air vent strip passes through the middle filter plate and has a gear-shaped cross-section.

6. The adsorption tank according to claim 1, characterized in that, A U-shaped baffle is provided at the bottom of the carbon canister, with a height of 1 / 4 to 1 / 2 of the height of the lower partition; it is used to separate the areas connecting the adsorption nozzle and the desorption nozzle assembly.

7. A ventilation system for a methanol-fueled aircraft, characterized in that, The ventilation system includes: The adsorption tank according to any one of claims 1-6; The vent connector assembly connects to the atmospheric inlet via an atmospheric hose. The adsorption nozzle is connected to the vent float valve via a methanol fuel tank hose, and the vent float valve is placed inside the methanol fuel tank. The desorption nozzle assembly is connected to the engine intake manifold via an engine hose. The adsorption tank is equipped with a temperature sensor. The outside of the adsorption tank is wrapped with a heating element.

8. The ventilation system according to claim 7, characterized in that, The heating components do not operate when the engine is not running; When the engine is running, the control heating component heats the adsorption tank to the rated temperature to promote methanol desorption.

9. The ventilation system according to claim 7, characterized in that: The flow area of ​​the engine hose is Q1, the total flow area of ​​the methanol fuel tank hose is Q2, and the flow area of ​​the atmospheric hose is Q3. Q3 = Q1 ≥ 2Q2.

10. An aircraft, characterized in that: The ventilation system included in any one of claims 7-9.

Images