A cantilever rotor device suitable for afterburning booster systems

Abstract

This invention relates to a cantilevered rotor device suitable for afterburning turbocharging systems, applied in turbochargers within such systems. The radial turbine and rotor shaft are friction-welded together. Bearings, a centrifugal compressor, an axial-radial damper, and the radial turbine are arranged sequentially on the rotor shaft from front to back. The bearings enable a cantilevered rotor system arrangement. The axial-radial damper dissipates axial and radial vibration energy of the rotor system. A thermal insulation sealing device is mounted on a stationary component, located between the radial turbine and the centrifugal compressor impeller. One side of the centrifugal compressor is connected to the front end via an end-face fit, and the other side is connected to the axial-radial damper via an end face, pressing it against the rotor shaft shoulder. The centrifugal compressor impeller and the radial turbine are arranged back-to-back. The thermal insulation sealing device achieves thermal isolation and seals against high-pressure gas leakage at the dynamic-static interface. This invention has advantages such as compact structure, small axial dimension, reliable support, low failure rate, and wide applicability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of aero-engine, and particularly relates to a cantilever type rotor device suitable for a supplementary combustion supercharging system, in particular to a micro turbocharger rotor support structure, in addition, the present application also relates to the corresponding damping, heat insulation and bearing cooling mode of the rotor support structure. BACKGROUND

[0002] The micro turbo machine is a high-speed rotating machine, which is widely applied in various fields such as an aero-piston engine, a distributed energy and a passenger car, and if it should be in a turbocharger, the rotating speed can reach 200000r / min, and the rotor crosses multiple critical rotating speeds. The change of the rotor operating environment causes the axial and radial vibration of the rotor system, the sharp change of the temperature and pressure of the compressor and the turbine front and back sections, and the rubbing between the rotating part and the stationary part, which seriously endangers the safe operation of the equipment.

[0003] In order to enable the high-speed rotating machine and the rotor system to stably operate, various rotor arrangement forms, as well as the damping and bearing cooling and lubrication modes of the rotor have been researched at home and abroad, and at present, the 0-1-0 type rotor arrangement form is mostly adopted. However, in this arrangement form, the bearing lubrication and detection are difficult, and the bearing is close to the turbine end and is easily affected by the high temperature of the turbine end, which affects the service life of the bearing. SUMMARY

[0004] In order to solve the above technical problems, the present application provides a set of stable and reliable rotor support, damping, heat insulation and bearing cooling scheme for the micro high-speed rotor system, so as to solve the problems of high-speed rotor vibration and bearing cooling, and make the micro turbo machine compact in structure, small in axial size and reliable in operation.

[0005] The complete technical scheme of the present application comprises:

[0006] A cantilever type rotor device suitable for a supplementary combustion supercharging system, the cantilever type rotor device comprises a rotating shaft 1, the rotating shaft 1 is sequentially provided with a bearing 2, a centrifugal compressor impeller 3, an axial radial damper 4 and a radial flow turbine 6 from front to back; characterized in that the bearing 2 is located at the front end of the rotating shaft 1, and the centrifugal compressor impeller 3 and the radial flow turbine 6 are located at the other end of the rotating shaft 2.

[0007] The centrifugal compressor impeller 3 and the radial flow turbine 6 adopt a back-to-back form, and the axial radial damper 4 and the heat insulation sealing device 5 are arranged in the middle; the hot end and the cold end are separated.

[0008] The centrifugal compressor impeller 3 is connected with the bearing 2 in an end face matching mode, and the other end face of the centrifugal compressor impeller 3 is connected with the axial radial damper 4 and the axial radial damper 4 is pressed against the shaft shoulder of the rotating shaft 1; the axial radial damper 4 can generate axial and radial damping and dissipate rotor vibration energy when the cantilever rotor device is running;

[0009] The heat insulation sealing device 5 is located between the radial turbine 6 and the centrifugal compressor impeller 3, and the heat insulation sealing device 5 is installed on a stationary part, and the heat insulation sealing device 5 seals the high-pressure gas leaked from the dynamic and static interface through the matching between the inner cylindrical surface and the rotating shaft 1.

[0010] Further, the rotating shaft 1 and the radial turbine 6 are welded by friction welding. The bearing 2, the centrifugal compressor impeller 3 and the axial radial damper 4 are sequentially pressed against the shaft shoulder of the rotating shaft 1 by the pressing nuts, the torque is transmitted by the end face friction force of each part and the parts are connected together to realize the integrated design of the rotor system. The above-mentioned bearing 2 is arranged away from the radial turbine 6, away from the hot end part, reduces the thermal load of the bearing 2, and is conducive to the cooling and lubrication of the bearing 2.

[0011] Further, the cantilever rotor device is supported by the front bearing 2, the front end face of the centrifugal compressor impeller 3 is connected with the bearing 2, the bearing 2 is located at the front end of the rotating shaft 1 and at the inlet of the centrifugal compressor impeller 3, and when the centrifugal compressor impeller 3 rotates at high speed, part of the inlet air passes through the bearing 2 and cools the bearing 2. At the same time, the bearing 2 is located at the front of the rotor system, which is convenient for lubrication.

[0012] Further, the axial radial damper 4 is installed on the rotating shaft 1, and when the cantilever rotor device rotates at high speed, axial and radial vibrations are generated. If the vibrations are not inhibited and dissipated, the dynamic and static parts will be rubbed. The axial end face of the axial radial damper 4 and the stationary part form a first small gap, and the radial outer cylindrical surface of the axial radial damper 4 and the stationary part form a second small gap; with the high-speed rotation of the rotating shaft 1, the airflow in the first small gap and the second small gap rotates at high speed and is extruded, which dissipates the rotor vibration energy and ensures the stable operation of the cantilever rotor device.

[0013] The gap width is related to the rotating speed and the pressure value in the disc cavity. Under the working condition that the working rotating speed is 120000-16000 rpm and the disc cavity pressure is 1.1 standard atmospheres, the width of the first small gap and the second small gap is 0.4mm-0.5mm, which can achieve good vibration reduction effect.

[0014] Further, the heat insulation sealing device 5 is a plate-shaped metal sheet welding piece, and the inside can pass through gas; the gas flowing through the radial turbine 6 transmits heat to the heat insulation sealing device 5 through heat conduction and heat radiation, and the heat insulation sealing device 5 takes away the heat through the partition plate and internal airflow, so that the heat is prevented from being transmitted to the centrifugal compressor impeller 3 and the front end bearing 2.

[0015] Further, the inner cylindrical surface of the heat insulation sealing device 5 and the outer cylindrical surface of the rotating shaft 1 are matched to form a third small gap, the airflow in the third small gap is rotated at high speed by the high-speed rotation of the rotating shaft 1, and the rotating sealing effect is achieved, so that the high-pressure gas is sealed.

[0016] The gap width between the inner cylindrical surface of the heat insulation sealing device 5 and the outer cylindrical surface of the rotating shaft 1 is related to the design rotating speed and pressure, and under the working condition that the working rotating speed is 120000-16000 rpm and the pressure is 1.1 atm, the width of the third small gap is 0.4 mm-0.5 mm, so that the effect of maintaining the rotor stability can be better achieved.

[0017] Further, the cantilever rotor device is installed on a turbocharger of a reheat pressurization system.

[0018] Compared with the prior art, the advantages of the present application are that:

[0019] 1. The axial-radial damper 4 is installed behind the centrifugal compressor impeller 3, and a small gap is formed between the end surface of the axial-radial damper 4 and the stationary part. The axial-radial damper 4 rotates at high speed together with the rotating shaft 2, and a rotating flow is formed in the small gap. When the rotating shaft 2 is subjected to axial vibration, the axial-radial damper 4 will squeeze the rotating flow in the small gap, and the squeezing process is an energy dissipation process. The axial vibration of the rotor can be weakened. When the rotor system is subjected to radial vibration, a small gap is also formed between the outer cylindrical surface of the axial-radial damper 4 and the stationary part. The flow in the small gap also rotates with the high movement of the axial-radial damper 4, and the radial vibration makes the small gap larger. In the process of becoming smaller, the airflow in the small gap is subjected to energy dissipation, so that the radial vibration is dissipated. The axial-radial damper 4 dissipates the vibration energy of the rotor system, and the stable operation of the rotor system is realized.

[0020] 2. The heat insulation sealing device 5 is arranged between the centrifugal compressor impeller 3 and the radial turbine 6. The device is made of plate metal sheet welding, and the middle part is ventilated. The heat transmitted to the heat insulation sealing device 5 by gas conduction and radiation is taken away by airflow. At the same time, the inner cylindrical surface of the heat insulation sealing device 5 and the rotating shaft 2 are matched to form a small gap. The flow in the small gap rotates at high speed and has a sealing effect. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is a structural schematic view of the rotor device of the present application.

[0022] Figure 2It is the structure schematic diagram of the afterburning supercharging system with the rotor device of the application.

[0023] Figure 3 It is the internal structure diagram of the jet combustion chamber of the afterburning supercharging system.

[0024] Wherein, 1-rotor shaft; 2-bearing; 3-centrifugal compressor impeller; 4-axial radial damper; 5-heat insulation sealing device; 6-radial turbine; 7-engine exhaust pipe, 8-afterburning combustor, 9-turbocharger, 10-starting and launching integrated motor, 11-swirl combustion chamber, 12-jet combustion chamber, 13-exhaust pipe inlet, 14-afterburning combustor outlet, 15-turbocharger outlet, 16-afterburning combustor fuel inlet, 17-afterburning combustor air inlet, 18-silicon nitride heating rod, 19-primary swirl zone, 20-secondary swirl zone, 21-jet zone. DETAILED DESCRIPTION

[0025] The technical solutions of the application will be further described in detail below with reference to the drawings of the application. Obviously, the described embodiments are only used as examples and are not used to limit the present application.

[0026] The specific embodiments of the application will be further described in detail below with reference to the drawings.

[0027] As Figure 1 shown, the cantilever rotor device suitable for the afterburning supercharging system disclosed by the application comprises a rotor shaft 1 and a radial turbine 6 which are friction-welded together. The bearing 2, the centrifugal compressor impeller 3, the axial radial damper 4 and the radial turbine 6 are arranged in sequence from front to back on the rotor shaft 1.

[0028] The heat insulation sealing device 5 is located between the centrifugal compressor impeller 3 and the radial turbine 6. One side of the centrifugal compressor impeller 3 is connected with the bearing 2 in an end face matching manner, and the other side end face of the centrifugal compressor impeller 3 is connected with the axial radial damper 4. The bearing 2, the centrifugal compressor impeller 3 and the axial radial damper 4 are pressed tightly on the shaft shoulder of the rotor shaft 1 by using a front end nut, so as to realize the assembly of the rotor system.

[0029] The centrifugal compressor impeller 3 and the radial turbine 6 adopt a back-to-back form and are separated by the axial radial damper 4 and the heat insulation sealing device 5. The bearing 2 is located at the most front end of the rotor shaft 1 and supports the whole rotor system, and the rotor is cantilever supported. When the rotor system rotates at high speed, the air entering the front end of the centrifugal compressor impeller 3 is partially cooled by the bearing 2.

[0030] Meanwhile, the axial and radial dampers 4 can generate axial and radial damping when the rotor system is running, and dissipate the rotor vibration energy; the axial end surface of the axial and radial dampers 4 and the stationary part form a first small gap, and the radial outer cylindrical surface of the axial and radial dampers 4 and the stationary part form a second small gap; with the high-speed rotation of the rotating shaft 1, the airflow in the first small gap and the second small gap is extruded at high speed, and the effect of dissipating the rotor vibration energy is achieved, thereby ensuring the stable operation of the cantilevered rotor device.

[0031] The heat insulation sealing device 5 is fixed on the stationary part, and the inside is ventilated, so that the heat brought by the gas radiation and transmission can be taken away, and heat insulation is achieved. The cooperation between the inner cylindrical surface of the heat insulation sealing device 5 and the rotating shaft 1 seals the high-pressure gas leaked from the dynamic and static interface. Further, the inner cylindrical surface of the heat insulation sealing device 5 and the outer cylindrical surface of the rotating shaft 1 cooperate to form a third small gap, and the airflow in the third small gap is rotated at high speed by the high-speed rotation of the rotating shaft 1, thereby achieving the effect of rotary sealing and sealing the high-pressure gas.

[0032] The gap width is related to the rotating speed and the pressure value in the disc cavity. Under the working condition that the working rotating speed is 120000-16000 rpm and the pressure in the disc cavity is 1.1 standard atmospheres, the width of the first small gap and the second small gap is 0.4mm-0.5mm, which can achieve a better vibration reduction effect.

[0033] The gap width between the inner cylindrical surface of the heat insulation sealing device 5 and the outer cylindrical surface of the rotating shaft 1 is related to the designed rotating speed and pressure. Under the working condition that the working rotating speed is 120000-16000 rpm and the pressure is 1.1 atmospheres, the width of the third small gap is 0.4mm-0.5mm, which can achieve a better effect of maintaining the stability of the rotor.

[0034] The embodiment also discloses a reburning supercharging system applying the cantilevered rotor device. Figure 2 As shown in the figure, the reburning supercharging system further comprises an engine exhaust pipe 7, a reburning combustor 8, and a start-up integrated motor 10; the exhaust pipe inlet 13 of the engine exhaust pipe 7 is connected with the engine exhaust port, the engine exhaust pipe 7 is communicated with the reburning combustor 8, the outlet 14 of the reburning combustor is connected with the turbocharger and can drive the turbine of the turbocharger 9 to work, the outlet 15 of the turbocharger 9 is connected with the engine air box, the engine air box is connected with the air inlet 17 of the reburning combustor 8, and the start-up integrated motor 10 is connected with the turbocharger 9 through a shaft coupling and transmits torque.

[0035] The exhaust gas of the engine enters the reburning combustor 8 through the engine exhaust pipe inlet to perform secondary combustion, and the high-temperature gas after combustion enters the turbine of the turbocharger 9 through the reburning combustor outlet 14 and drives the turbine to work.

[0036] The compressed air provided by the turbocharger 9 enters the engine air box through the turbocharger outlet 15 to provide scavenging pressure for engine starting; at the same time, the compressed air enters the afterburning combustor 8 through the air inlet 17 of the afterburning combustor 8.

[0037] Further, the turbocharger 9 provides electric energy output through the control start integrated motor 10, and adjusts the pressure of the turbocharger compressor outlet 15 through the size of the electric energy output.

[0038] Further, the afterburning combustor 8 includes a jet combustion chamber 12 and a swirl combustion chamber 11, and the jet combustion chamber 12 is provided with a fuel inlet 16, an air inlet 17 and a silicon nitride heating rod 18.

[0039] Further, the high-temperature gas in the engine exhaust pipe 7 and the afterburning combustor 8 all enter the turbine inlet of the turbocharger 9 through the afterburning combustor outlet 14.

[0040] Further, the engine exhaust pipe 7 is connected with the afterburning combustor 8 through a tight seal, and the connection of the engine exhaust pipe 7 with the afterburning combustor 8 through this connection mode can ensure the assembly accuracy of the exhaust pipe and reduce the assembly difficulty.

[0041] Further, the turbocharger 9 and the afterburning combustor 8 are connected through flanges at the afterburning combustor outlet 14 and the flange surfaces are pressed by nuts.

[0042] Further, the control start integrated motor 10 is fixed on the turbocharger 9 through a motor support, and the shaft of the control start integrated motor 10 and the shaft of the turbocharger 9 are connected through a coupling to transmit torque.

[0043] Further, when the engine starts, the control start integrated motor 10 drives the turbocharger 9 to rotate, and the high-temperature gas discharged by the afterburning combustor 8 enters the turbocharger 9 to drive the turbine of the turbocharger 9 to work, at this time, the working mode of the control start integrated motor 10 is changed to power generation mode.

[0044] The afterburning combustor 8 is highly integrated with the engine exhaust pipe 7, the airflow compressed by the compressor enters the engine air box through the compressor outlet 15, the air in the engine air box enters the jet combustion chamber 12 of the afterburning combustor 8 through the air inlet 17 of the afterburning combustor 8 and burns in the jet combustion chamber 12 to form high-temperature gas in the form of jet to enter the swirl combustion chamber 11 of the afterburning combustor 8; at the same time, the engine exhaust enters the swirl combustion chamber 11 after passing through the engine exhaust pipe 7, and the two parts of high-temperature gas continue to burn in the swirl combustion chamber 11, and the high-temperature gas after burning enters the turbine of the turbocharger 9 to drive the turbine to work, and the turbine of the turbocharger 9 drives the compressor and the control start integrated motor 4 of the turbocharger 9 to rotate at high speed.

[0045] Meanwhile, in the regulation of the afterburning supercharging system, the rotational speed of the turbocharger 9 is regulated by controlling the power generation of the start-launch integrated motor 10, the pressure at the outlet 15 of the turbocharger compressor is regulated, and thus the pressure in the air box behind the turbocharger 9 is regulated. The temperature before the turbine of the turbocharger 9 is regulated by controlling the size of the fuel injection amount of the afterburning combustor 8, the power of the turbine is changed, and the air box pressure can also be regulated. Both of the two regulation modes can regulate the air box pressure without air release before the turbine of the turbocharger 9, and the combined use of the two regulation modes can maximize the utilization efficiency of the exhaust gas energy of the engine. The turbocharger 9 provides both scavenging pressure and electric energy output for the engine, and this regulation mode of the afterburning supercharging system can simplify the regulation mechanism of the turbocharger 9 and improve the recovery efficiency of the exhaust gas energy.

[0046] The afterburning combustor 8 of the afterburning supercharging system includes a nozzle, and the nozzle includes a fuel nozzle core located at the fuel inlet 16 of the afterburning combustor.

[0047] As shown in Figure 3 , the jet combustion chamber 12 includes a primary swirling zone 19, a secondary swirling zone 20, and a jet zone 21; the fuel nozzle core is used to guide the fuel into the primary swirling zone 19; the primary swirling zone 19 is in communication with the secondary swirling zone 20, and the secondary swirling zone 20 is in communication with the jet zone 21.

[0048] The silicon nitride heating rod 18 is arranged in the secondary swirling zone 20 and is used to ignite the gas mixed with atomized fuel in the secondary swirling zone 20; the jet zone 21 is in communication with the swirling combustion chamber 11.

[0049] Optionally, the primary swirling zone 19, the secondary swirling zone 20, and the jet zone 21 are all cylindrical cavities.

[0050] Optionally, the swirling combustion chamber 11 includes a plurality of shell surfaces, the afterburning combustor outlet 14 is arranged on a first shell surface and extends from the outside of the shell into the swirling combustion chamber 11 to a central position inside the cavity of the swirling combustion chamber 11, and the ratio of the diameter of the jet zone 21 to the diameter of the secondary swirling zone 20 is 3:5 to 2:5; a first engine exhaust pipe and / or a second engine exhaust pipe are arranged on a third shell surface and / or a fourth shell surface adjacent to the first shell surface and the second shell surface, respectively.

[0051] Further, the ratio of the engine displacement to the volume of the swirling combustion chamber 11 is 50:1 to 65:1.

[0052] Further, the cross section of the swirling combustion chamber 11 is a rounded rectangular cavity or a primitive shape.

[0053] Optionally, the first engine exhaust pipe and the second engine exhaust pipe are respectively connected with the swirl combustion chamber 11 and the engine exhaust pipe, and the engine exhaust gas enters the swirl combustion chamber 11 along the tangential direction through the first engine exhaust pipe and the second engine exhaust pipe, and is fully mixed in the swirl combustion chamber 11, and the HC, CO and carbon nucleus particles in the engine exhaust gas are further combusted and converted into CO2 and H2O in the swirl combustion chamber 11, and chemical energy is released at the same time.

[0054] Optionally, the first engine exhaust pipe and the second engine exhaust pipe are oppositely arranged on the two sides of the swirl combustion chamber 11 with the outlet 14 of the afterburning combustor as the boundary, and the engine exhaust gas enters the swirl combustion chamber 11 along the tangential direction from the two sides, and the counterflow gas is convenient to form the swirl in the combustion chamber, and is fully mixed with the high-temperature gas entering the combustion chamber through the jet area 21, so that the secondary combustion effect is better.

[0055] Optionally, the gas introduction hole is arranged on one side of the air inlet 17 of the afterburning combustor, the gas introduction hole is a centripetal hole, and the gas introduction hole is connected with the air inlet 17 of the afterburning combustor and the secondary swirl area 20; the axis of the gas introduction hole is arranged at an angle with the axis of the secondary swirl area 20; the tangential velocity can be generated when the gas flows, so that the swirl is convenient to generate; the cross-sectional area of the air inlet 17 of the afterburning combustor is equal to the cross-sectional area of the swirl hole of the primary swirl area.

[0056] Optionally, the cavity volumes of the primary swirl area 19, the jet area 21, the secondary swirl area 20 and the swirl combustion chamber 11 are sequentially increased.

[0057] When the combustor works before the engine works, the silicon nitride heating rod 18 is preheated first, the fuel enters the nozzle through the fuel inlet, passes through the fuel guide pipe, is sprayed out through the oil outlet hole, flows through the spiral oil channel on the fuel nozzle core 1, and enters the inclined chute at the end of the spiral oil channel to enter the primary swirl area 19; the gas enters the afterburning combustor from the air inlet 17 of the afterburning combustor, part of the gas flows into the primary swirl area 19 through the swirl hole of the primary swirl area 19, and the other part of the gas directly enters the secondary swirl area 20 from the gas introduction hole of the secondary swirl area 20; the fuel in the primary swirl area 19 is fully mixed with the gas entering the primary swirl area 19 through the swirl hole of the primary swirl area, and then enters the secondary swirl area 20, is ignited by the silicon nitride heating rod 18 inserted into the secondary swirl area 20, and then is mixed and combusted with the gas entering the secondary swirl area 20 through the gas introduction hole, and continues to be combusted; then the gas enters the jet area 21, and the flame is reversely propagated to the primary swirl area 19, the silicon nitride heating rod 18 is powered off, and the ignition process is completed.

[0058] When the engine works prior to the combustor: after the engine is started, the exhaust gas temperature of the engine reaches the threshold temperature (usually 300 DEG C), the silicon nitride heating rod 18 is preheated, the fuel enters the nozzle through the fuel inlet, then passes through the fuel guide pipe from the oil outlet hole into the inclined slot at the end of the spiral oil channel to spray into the primary swirling area 19, and after mixing with the gas from the air inlet 17 of the supplementary combustion combustor, it enters the secondary swirling area 20 to start mixing combustion, and then passes through the jet area 21 into the swirling combustion chamber 11 for secondary combustion, and is ignited by the high-temperature tail gas in the swirling combustion chamber 11, the flame propagates back to the primary swirling area 19, and then the silicon nitride heating rod 18 is turned off, and the ignition process is completed.

[0059] The high-temperature gas in the primary swirling area 19 continues to mix and burn with the gas in the secondary swirling area 20, and then enters the jet area 21 to expand and accelerate, enters the swirling combustion chamber 11, and mixes with the piston engine exhaust gas from the first engine exhaust pipe into the swirling combustion chamber 11 to perform secondary combustion. In the process of secondary combustion, HC, CO and carbon nucleus particles continue to burn, convert into CO2 and H2O, release energy, and the completely burned gas is discharged through the supplementary combustion combustor outlet 14 of the swirling combustion chamber.

[0060] In the present application, the primary swirling area 19 realizes sufficient mixing of gas and fuel through the swirling holes opposite to the inclined slot. At the same time, due to the slow flow rate ratio of gas and fuel in the primary swirling area to that in the secondary swirling area, the mixed gas flow can be fully burned in the primary swirling area, which is the main combustion area after stable combustion. The secondary swirling area 20 realizes ignition at start-up and performs combustion reaction as a secondary combustion area. First, the gas enters the combustor along the tangential direction to form a pre-rotation effect in the cavity of the supplementary combustion combustor air inlet 17. Part of the gas enters the primary swirling area 19 along the tangential direction through the side wall swirling hole of the primary swirling area 19 to form a primary swirling flow. Another part of the gas enters the secondary swirling area 20 along the tangential direction of the combustor through the gas introduction hole of the side wall of the supplementary combustion combustor air inlet 17 to generate a secondary swirling flow. The jet area 21 makes the high-temperature gas expand and accelerate to enter the swirling combustion chamber 11.

[0061] The primary swirling area 19 enters the secondary swirling area 20 as a primary swirling flow. When the gas enters the secondary swirling area 20 from the supplementary combustion combustor air inlet 17, it naturally generates a swirling flow through the gas introduction hole (swirling hole). Since the gas introduction hole is uniformly distributed along the cross section, the primary swirling flow and the secondary swirling flow form a secondary swirling flow when they converge in the secondary swirling area 20, which strengthens the primary swirling flow.

[0062] The jet is realized through the jet area 21. The jet area 21 connects the secondary swirling area 20 and the swirling combustion chamber 11. The internal space of the secondary swirling area 20 is smaller than that of the swirling combustion chamber 11, so that a pressure difference is generated on both sides of the jet area 21. When the swirling flow passes through the jet area 21, it accelerates, and after entering the swirling combustion chamber 11, it is free from the constraint of the pipe wall of the jet area 21 to form a jet.

[0063] So far, the technical solutions of the present application have been described in combination with the drawings, but it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to the related technical features without departing from the principles of the present application, and the technical solutions after the changes or replacements will all fall within the protection scope of the present application.

Claims

1. A system for afterburning supercharging with a cantilevered rotor device, said cantilevered rotor device comprising a shaft (1) provided with, in order from front to back, a bearing (2), a centrifugal compressor impeller (3), an axial-radial damper (4) and a radial turbine (6); characterized in that, The bearing (2) is located at the front end of the rotating shaft (1), and the centrifugal compressor impeller (3) and the radial turbine (6) are located at the other end of the rotating shaft (1); The centrifugal compressor impeller (3) and the radial turbine (6) adopt a back-to-back form, and an axial radial damper (4) and a heat insulation sealing device (5) are arranged therebetween; One side of the centrifugal compressor impeller (3) is connected with the bearing (2) in an end face matching mode, and the other side end face of the centrifugal compressor impeller (3) is connected with the axial radial damper (4) and presses the axial radial damper (4) against the shaft shoulder of the rotating shaft (1); the axial radial damper (4) can generate axial and radial damping and dissipate rotor vibration energy when the cantilever rotor device operates; The heat insulation sealing device (5) is located between the radial turbine (6) and the centrifugal compressor impeller (3), and the heat insulation sealing device (5) is mounted on a stationary part; the heat insulation sealing device (5) seals the high-pressure gas leaked from the dynamic and static interface through the cooperation between the inner cylindrical surface and the rotating shaft (1). The afterburning supercharging system comprises a turbocharger, the cantilever rotor device is mounted on the turbocharger, and the afterburning supercharging system further comprises an engine exhaust pipe, an afterburning combustor and a start-up integrated motor; the afterburning combustor comprises a jet combustion chamber and a swirl combustion chamber, and the jet combustion chamber is provided with an afterburning combustor fuel inlet, an afterburning combustor air inlet and a silicon nitride heating rod; The afterburning combustor further comprises a nozzle, and the nozzle comprises a fuel nozzle core and is located at the afterburning combustor fuel inlet; The jet combustion chamber comprises a primary swirl zone, a secondary swirl zone and a jet zone; the fuel nozzle core is used for guiding fuel into the primary swirl zone; the primary swirl zone is in communication with the secondary swirl zone, and the secondary swirl zone is in communication with the jet zone; The volume of the primary swirl zone, the jet zone, the secondary swirl zone and the swirl combustion chamber increases in sequence; The engine exhaust pipe inlet is connected with an engine exhaust port, the engine exhaust pipe is in communication with the afterburning combustor, the afterburning combustor outlet is connected with the turbocharger and can drive the turbine of the turbocharger to work, the outlet of the turbocharger is connected with an engine air box, the engine air box is connected with the afterburning combustor air inlet, and the start-up integrated motor is connected with the shaft of the turbocharger through a shaft coupling and transmits torque; The exhaust gas of the engine enters the afterburning combustor through the engine exhaust pipe inlet to be combusted again, and the high-temperature gas after combustion enters the turbine of the turbocharger through the afterburning combustor outlet and drives the turbine to work. The compressed air provided by the turbocharger enters the engine air box through the outlet of the turbocharger to provide scavenging pressure for engine starting; at the same time, the compressed air enters the afterburning combustor through the afterburning combustor air inlet from the engine air box.

2. The afterburner supercharging system with a cantilevered rotor device according to claim 1, characterized in that: The rotating shaft (1) and the radial turbine (6) are welded by friction welding.

3. The afterburner supercharging system with a cantilevered rotor device according to claim 1, characterized in that: The bearing (2) at the front end of the cantilever rotor device supports the entire cantilever rotor device, the front end face of the centrifugal compressor impeller (3) is connected with the bearing (2), and the axial intake of the centrifugal compressor impeller (3) cools the bearing (2).

4. The afterburner supercharging system with a cantilevered rotor device according to claim 1, characterized in that: The axial end surface of the axial-radial damper (4) and the stationary part form a first small gap, and the radial outer cylindrical surface of the axial-radial damper (4) and the stationary part form a second small gap; as the rotating shaft (1) rotates at high speed, the airflow in the first small gap and the second small gap is extruded and rotates at high speed, and the effect of dissipating the rotor vibration energy is guaranteed, so that the cantilever rotor device operates stably.

5. The afterburner supercharging system with a cantilevered rotor device according to claim 4, characterized in that: Under the working condition of a working rotational speed of 120000-16000 rpm and a disc cavity pressure of 1.1 standard atmospheres, the width of the first small gap and the second small gap is 0.4mm-0.5mm.

6. The afterburner supercharging system with a cantilevered rotor device according to claim 1, characterized in that: The heat-insulating sealing device (5) is a plate-shaped sheet metal welded part, and the inside thereof can pass through gas; the gas flowing through the radial turbine (6) transmits heat to the heat-insulating sealing device (5) through heat conduction and heat radiation, the heat-insulating sealing device (5) takes away the heat through the partition plate and the internal airflow, and heat is prevented from being transmitted to the centrifugal compressor impeller (3) and the front bearing (2).

7. The afterburner supercharging system with a cantilevered rotor device according to claim 1, characterized in that: The inner cylindrical surface of the heat-insulating sealing device (5) and the outer cylindrical surface of the rotating shaft (1) are matched to form a third small gap, the airflow in the third small gap is driven to rotate at high speed by the high-speed rotation of the rotating shaft (1), and the rotating sealing effect is achieved, and the high-pressure gas is sealed.

8. The afterburner supercharging system with a cantilevered rotor device according to claim 7, characterized in that: Under the working condition of a working rotational speed of 120000-16000 rpm and a pressure of 1.1 atmospheres, the width of the third small gap is 0.4mm-0.5mm.

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