Turbojet engine started through air inlet pressurization

Abstract

The turbojet engine comprises a shell, a starting motor, an air supply assembly and a pressure sensor, a flow guide cover is arranged at the front end of the shell, an air inlet casing is arranged on the inner side of the flow guide cover, a cavity is defined by the air inlet casing and the flow guide cover, and the starting motor is arranged in the middle of the front end of the air inlet casing. An air inlet structure is arranged on the box wall of the air inlet box, and the air inlet structure communicates with the cavity and the air inlet box; the air supply assembly comprises an air pipe communicated with the air source and a switch component arranged on the air pipe, an air outlet of the air pipe is communicated with the cavity, the switch component is electrically connected with the engine electronic control unit, and the pressure sensor is electrically connected with the engine electronic control unit. During use, the pressure sensor detects atmospheric pressure in real time, the engine electric control unit switches on and off the air supply assembly according to the atmospheric pressure, and normal starting can be achieved when the atmospheric pressure is low. Therefore, the turbojet engine provided by the utility model can be reliably started under different atmospheric pressures, and has good compatibility.

Description

Technical Field

[0001] The utility model relates to the technical field of turbojet engines, in particular to a turbojet engine with air intake pressurization starting. Background Art

[0002] When a turbojet engine is started in an area with low atmospheric pressure, such as in a plateau, because such areas are usually at high altitudes and have thin air, the compressor inlet pressure is low, oxygen is insufficient, and the air-fuel ratio is relatively low. This results in excessively high gas temperature on the one hand, and on the other hand, blocks the air entering the compressor, increasing the torque that rotates the compressor, causing the engine speed to stagnate at a certain speed and unable to rise, leaving the engine in a suspended state, resulting in a technical problem of difficulty in starting. Utility Model Content

[0003] In view of the above-mentioned deficiencies, the technical problem to be solved by the utility model is to provide a turbojet engine with intake pressurized starting, which can start reliably under different atmospheric pressures by adding an air supply component and a pressure sensor, and has good compatibility.

[0004] In order to solve the above technical problems, the technical solution of the utility model is:

[0005] A turbojet engine with air intake pressure start, comprising a shell and a starter motor, a shroud is provided at the front end of the shell, an air intake casing is provided on the inner side of the shroud, a cavity is formed between the air intake casing and the shroud, and the starter motor is arranged in the middle of the front end of the air intake casing, an air intake structure is provided on the casing wall of the air intake casing, and the air intake structure connects the cavity and the air intake casing; the turbojet engine with air intake pressure start also includes an air supply component and a pressure sensor; the air supply component includes an air pipe connected to an air source, and a switch component provided on the air pipe, the air outlet of the air pipe is connected to the cavity, and the switch component is electrically connected to an engine electronic control unit; the pressure sensor is electrically connected to the engine electronic control unit, the pressure sensor is used to detect atmospheric pressure, and convert it into a corresponding voltage signal and transmit it to the engine electronic control unit, and the engine electronic control unit controls the switch of the switch component according to the voltage signal.

[0006] Preferably, the air intake structure includes a plurality of air intake holes, and all of the air intake holes are arranged along the circumference of the air intake casing.

[0007] Preferably, all the air inlet holes are arranged evenly.

[0008] Preferably, the air intake structure includes a plurality of air intake holes, and all of the air intake holes are arranged in a staggered manner along the circumference of the air intake casing.

[0009] Preferably, the air intake structure includes a plurality of air intake guide holes, and all of the air intake guide holes are arranged close to the rear end of the air intake casing.

[0010] Preferably, the gas source is a gas cylinder, and the gas outlet of the gas cylinder is connected to the gas inlet of the gas pipe.

[0011] Preferably, the gas cylinder, the gas pipe and the switch component are accommodated in the cavity.

[0012] Preferably, the switch component is a solenoid valve.

[0013] A preferred embodiment is that a combustion chamber, a fuel system, a rotor, a turbine installed at the rear end of the rotor, a bladed diffuser installed at the front end of the rotor and a compressor are arranged on the inner side of the casing, the air intake casing is covered on the outer side of the compressor, and the output shaft of the starter motor is connected to the compressor impeller.

[0014] Preferably, a mounting plate is further provided on the inner side of the shell, the mounting plate is respectively connected to the air duct and the air intake casing, the mounting plate, the bladed diffuser and the compressor impeller together form an air intake passage, and the air intake passage is connected to the combustion chamber.

[0015] After adopting the above technical solution, the beneficial effects of the utility model are:

[0016] The turbojet engine with air intake pressure start of the utility model includes a housing, a starter motor, an air supply assembly and a pressure sensor. The front end of the housing is provided with a deflector, the inner side of the deflector is provided with an air intake casing, a cavity is formed between the air intake casing and the deflector, the starter motor is provided in the middle of the front end of the air intake casing, an air intake structure is provided on the casing wall of the air intake casing, and the air intake structure is connected with the cavity and the air intake casing; the air supply assembly includes an air pipe connected with the air source, and a switch component provided on the air pipe, the air outlet of the air pipe is connected with the cavity, and the switch component is electrically connected with the engine electronic control unit; the pressure sensor is electrically connected with the engine electronic control unit. In actual use, the pressure sensor detects the atmospheric pressure in real time. When the atmospheric pressure is lower than the preset threshold, the engine electronic control unit opens the switch component and the air supply assembly is put into use. When the atmospheric pressure is not lower than the preset threshold, the engine electronic control unit closes the switch component. When the atmospheric pressure is low, the gas in the air supply assembly enters the combustion chamber through the cavity, the air intake structure, and the air intake casing, thereby achieving air intake pressurization, solving the problem of difficult starting, and enabling the turbojet engine of the utility model to start reliably under different atmospheric pressures and having good compatibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a turbojet engine for air intake pressurization starting in the utility model;

[0018] In the figure: 1-engine electronic control unit, 2-solenoid valve, 3-air pipe, 4-gas cylinder, 5-air deflector, 6-intake casing, 7-compressor impeller, 8-mounting plate, 9-intake hole, 10-starting motor, 11-vaned diffuser, 12-combustion chamber, 13-guide vane, 14-turbine. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0020] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside", and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0021] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0022] like Figure 1 As shown, a turbojet engine with air intake pressure start includes a housing and a starter motor 10. The inner side of the housing is provided with a combustion chamber 12, a fuel system, a rotor, a turbine 14 installed at the rear end of the rotor, a vaned diffuser 11 installed at the front end of the rotor, and a compressor. The outer cover of the compressor is provided with an intake casing 6. Specifically, a shroud 5 is provided at the front end of the housing, and the intake casing 6 is provided inside the shroud 5. A cavity is formed between the intake casing 6 and the shroud 5. The starter motor 10 is provided in the middle of the front end of the intake casing 6, and the output shaft of the starter motor 10 is connected to the compressor impeller 7. A mounting plate 8 is also provided on the inner side of the housing, and the mounting plate 8 is connected to the shroud 5 and the intake casing 6 respectively. The mounting plate 8, the vaned diffuser 11, and the compressor impeller 7 together form an intake channel, and the intake channel is connected to the combustion chamber 12.

[0023] like Figure 1As shown, the engine of the utility model also includes an air supply component and a pressure sensor; wherein the air supply component includes an air pipe 3 connected to the air source, and a switch component arranged on the air pipe 3, the air outlet of the air pipe 3 is connected to the cavity, and the switch component is electrically connected to the engine electronic control unit 1. The pressure sensor is electrically connected to the engine electronic control unit 1, and the pressure sensor is used to detect the atmospheric pressure, and convert it into a corresponding voltage signal and transmit it to the engine electronic control unit 1. The engine electronic control unit 1 controls the switch component to switch according to the voltage signal. In a preferred embodiment, the switch component is a solenoid valve 2. In this embodiment, the air source can be, but is not limited to, a gas cylinder 4, the air outlet of the gas cylinder 4 is connected to the air inlet of the air pipe 3, and the gas cylinder 4, the air pipe 3 and the switch component are stored in the cavity.

[0024] like Figure 1 As shown, in the utility model, an air intake structure is arranged on the casing wall of the air intake casing 6, and the air intake structure connects the cavity and the air intake casing 6. After the air supply assembly is put into use, the gas in the air pipe 3 enters the cavity, enters the air intake casing 6 through the air intake structure, and then enters the combustion chamber 12 through the air intake casing 6.

[0025] In this embodiment, the air intake structure includes a plurality of air intake holes 9, and all the air intake holes 9 are arranged along the circumference of the air intake casing 6. In a preferred embodiment, all the air intake holes 9 are arranged evenly, and this structural arrangement enables the gas to enter the air intake casing 6 evenly.

[0026] In some other embodiments of the utility model, the air intake structure includes a plurality of air intake holes 9, and all the air intake holes 9 are arranged in a staggered manner along the circumference of the air intake casing 6. The staggered arrangement ensures the structural strength of the air intake casing 6 and reduces the impact of the air intake structure on the air intake casing 6.

[0027] In some other embodiments of the utility model, the air intake structure includes multiple air intake guide holes, all of which are arranged near the rear end of the air intake casing 6, specifically, near the side of the compressor impeller 7, so that the gas can quickly and evenly enter the air intake casing 6 and approach the compressor impeller 7.

[0028] like Figure 1 As shown, the turbojet engine of the utility model can detect the atmospheric pressure in real time because the pressure sensor can detect the atmospheric pressure in real time, and can detect the atmospheric pressure of the environment in which the engine is working in real time. When the detected atmospheric pressure is lower than the preset threshold, it indicates that the engine may be in a plateau environment and may be difficult to start. At this time, the engine electronic control unit 1 controls the solenoid valve 2 to open, so that the oxygen in the gas cylinder 4 enters the cavity formed by the guide cover 5 and the air intake casing 6 through the air pipe 3, and then enters the inner hole of the air intake casing 6 through the air intake hole 9 on the air intake casing 6.

[0029] After the starter motor 10 starts working, it drives the compressor impeller 7 to rotate, so that negative pressure is formed in front of the inlet of the compressor impeller 7. Under negative pressure, more oxygen flows from the gas cylinder 4 to the compressor impeller 7, and the compressor impeller 7 pressurizes the inhaled oxygen. The pressurized oxygen enters the combustion chamber 12 through the channel formed by the mounting plate 8 and the vaned diffuser 11. The fuel system injects fuel according to the air-fuel ratio of the low atmospheric pressure mode (or called the plateau mode), and the fuel and oxygen are ignited in the combustion chamber 12. The burning flame and high-temperature gas are blown to the turbine 14 after passing through the guide 13, so that the turbine 14 rotates at a high speed. The turbine 14 drives the coaxial compressor impeller 7 to rotate. After the speed of the compressor impeller 7 is increased, a higher compressor after-pressure will be obtained, so that the engine can reach the slow speed in a short time.

[0030] When the pressure sensor detects that the atmospheric pressure of the working environment reaches or exceeds the preset threshold, the engine electronic control unit 1 will turn on the normal atmospheric pressure mode (or plain mode). That is, the engine electronic control unit 1 controls the solenoid valve 2 to close, and the oxygen in the gas cylinder 4 stops being transported. At this time, the fuel system injects fuel according to the air-fuel ratio of the plain mode, and the fuel and oxygen are ignited in the combustion chamber 12. The burning flame and high-temperature gas are blown to the turbine 14 after passing through the guide 13, causing the turbine 14 to rotate at a high speed. The turbine 14 drives the coaxial compressor impeller 7 to rotate. After the speed of the compressor impeller 7 is increased, a higher compressor after-pressure will be obtained, allowing the engine to reach a slow speed in a short time.

[0031] It can be seen that the turbojet engine of the present invention can be reliably started under different atmospheric pressures, has good compatibility, and has a simple structure and is easy to implement.

[0032] It should be noted that the ability to start quickly and reliably is one of the most important characteristics of an engine. The control of the starting process should ensure that the engine enters the slow-running state quickly and safely within a given time while meeting the aerodynamic stability and strength limits. This requires that the engine starting process should not experience surge stall and unstable working conditions, and should also start quickly and successfully without overheating. Since the plain environment is relatively favorable for engine operation and can be verified through a large number of tests, the starting performance is relatively easy to meet. However, in the plateau environment, due to the reduced air density, reduced air mass flow entering the engine, and reduced residual air coefficient, it is difficult to achieve a smooth start of the engine using the same control law as in the plain.

[0033] The engine starting process of the utility model is divided into three stages: the first stage is before the ignition is completed, the engine is completely driven by the starter; the second stage is from the successful ignition to the starter disengagement, the residual work of the engine acceleration process is provided by the starter and the engine; the third stage is from the starter disengagement to the engine slowing down, and the residual work generated by the engine turbine 14 is used for acceleration.

[0034] The starting execution process of the turbojet engine of the utility model is as follows: the ignition head is preheated for 3 seconds, the starter motor 10 drives the engine to work to 5000 revolutions, the oil pump motor enters the ignition setting speed, the ignition solenoid valve 2 opens, the oil injection ignition starts in the combustion chamber 12, and the turbine 14 starts to generate power. When the exhaust temperature is detected to be 10°C greater than the initial exhaust temperature, the ignition is determined to be successful. After the combustion chamber 12 is ignited, the main oil valve is opened at the same time, and the compressor rotor is driven by the starter and the turbine 14 at the same time. As the speed increases, the power generated by the turbine 14 increases rapidly. When the engine speed exceeds the minimum stable working speed, when the gas temperature before the turbine 14 is kept at the maximum allowable value, the power of the turbine 14 is greater than the power consumed by the compressor, and the engine speed can be driven by the residual power of the turbine 14 to increase. However, in order to increase the reliability of the start and shorten the start time, the starter should be turned off only when the speed is 1 to 2 times greater than the minimum stable working speed. After the starter is turned off, the engine speed continues to rise by relying on the residual power of the turbine 14. At this time, when the engine speed increases rapidly to the set value, the starter motor 10 is disengaged. The oil pump continues to add oil at a certain rate. When the engine speed is greater than the slow speed setting value, the oil pump reduces the oil. At this time, the engine will rise rapidly by inertia, and then automatically decelerate to the slow speed. At this time, the engine status displays "slow state", and the engine is successfully started.

[0035] In summary, in order to adapt to the starting requirements at different altitudes, the engine electronic control unit 1 of the utility model has: plain mode starting and plateau mode starting. The plain mode has a fast starting speed, and the plain mode is used as the basic data. Plateau mode starting: In plateau areas, the engine air flow is small, and the intake air flow is supplemented by intake pressure. At the same time, the oil supply law is adjusted so that the oil and gas at starting are increased by 6% to 10% compared with the plain mode. Automatically match the engine slow speed according to different altitudes, and use a closed loop to adjust the speed after entering the slow speed.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications made within the spirit and principles of the present invention, improvements to the turbojet engine with intake pressurized start, etc., should be included in the protection scope of the present invention.

Claims

1. A turbojet engine with air intake pressure start, comprising a housing and a starter motor, wherein a shroud is disposed at the front end of the housing, an air intake casing is disposed inside the shroud, a cavity is formed between the air intake casing and the shroud, and the starter motor is disposed in the middle of the front end of the air intake casing, characterized in that: An air intake structure is arranged on the wall of the air intake casing, and the air intake structure is connected with the cavity and the air intake casing; the engine also includes an air supply component and a pressure sensor; The air supply assembly includes an air pipe connected to an air source, and a switch component provided on the air pipe, an air outlet of the air pipe is connected to the cavity, and the switch component is electrically connected to an engine electronic control unit; The pressure sensor is electrically connected to the engine electronic control unit. The pressure sensor is used to detect atmospheric pressure and convert it into a corresponding voltage signal for transmission to the engine electronic control unit. The engine electronic control unit controls the switch component according to the voltage signal.

2. The turbojet engine with intake pressure start according to claim 1, characterized in that: The air intake structure comprises a plurality of air intake holes, and all the air intake holes are arranged along the circumference of the air intake casing.

3. The turbojet engine with intake pressure start according to claim 2, characterized in that: All the air inlet holes are evenly arranged.

4. The turbojet engine with intake pressure start according to claim 1, characterized in that: The air intake structure comprises a plurality of air intake holes, and all the air intake holes are arranged in a staggered manner along the circumference of the air intake casing.

5. The turbojet engine with intake pressure start according to claim 1, characterized in that: The air intake structure comprises a plurality of air intake guide holes, and all of the air intake guide holes are arranged near the rear end of the air intake casing.

6. The turbojet engine with intake pressure start according to claim 1, characterized in that: The gas source is a gas cylinder, and the gas outlet of the gas cylinder is connected to the gas inlet of the gas pipe.

7. The turbojet engine with intake pressure start according to claim 6, characterized in that: The gas cylinder, the gas pipe and the switch component are accommodated in the cavity.

8. The turbojet engine with intake pressure start according to claim 1, characterized in that: The switch component is a solenoid valve.

9. The turbojet engine with intake pressure start according to claim 1, characterized in that: The inner side of the shell is provided with a combustion chamber, a fuel system, a rotor, a turbine installed at the rear end of the rotor, a bladed diffuser installed at the front end of the rotor, and a compressor. The outer side of the compressor is covered with the air intake casing, and the output shaft of the starter motor is connected to the compressor impeller.

10. The turbojet engine with intake pressure start according to claim 9, characterized in that: A mounting plate is also provided on the inner side of the shell, and the mounting plate is respectively connected to the air guide cover and the air intake casing. The mounting plate, the vaned diffuser and the compressor impeller together form an air intake passage, and the air intake passage is connected to the combustion chamber.

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