During 1976~ 1985, * * solved 685 difficult problems. In the ал-3 1φ design, * * obtained 128 patents, used 5 1 engine, and operated for 22,000 hours.
ал-3 1φ has been improved, including the one with vector nozzle.
1.2 structure and system
In the support scheme, the low-pressure rotor has a four-point structure of 1-2- 1, and its coupling is used to transmit torque to ensure that the turbine shaft and compressor will not generate additional vibration due to the eccentricity of the rotor system when working. So the low-pressure rotor adopts four-point low-pressure coupling-multi-purpose, but the structure is complex.
The high-pressure rotor support scheme is 1-0- 1, and the intermediate roller bearing is used as the rear fulcrum of the steam turbine.
The inlet box of the inlet is made of all titanium and has 23 inlet guide vanes with variable camber. The leading edge of the guide vane is fixed and protected from freezing by the air from the seventh stage of the high-pressure compressor. The back is adjustable.
The fan has four stages of axial flow. The pressure increasing ratio is 3.6. The whole fan is made of all titanium. The blades of the first three stages are provided with damping bosses. The whole fan rotor is welded into an integral part by electron beam welding. There is an organic casing treatment ring cavity on the casing corresponding to the fourth stage rotor blades, that is, there are 400 chutes on the inner wall of the casing to improve the stable working margin of the fan. The fourth stage outlet rectifier blades are double-row cascade blades. The fan casing is segmented as a whole.
The 9-stage axial flow disks of high-pressure compressor 1~3 are welded together by electron beam, and the 4~6-stage disks are also welded together by electron beam. The 7~9 grade plates are single plates, which are connected with the 6 grade plates by long bolts. The tenons connecting the 9-stage disk and blades are all annular dovetail grooves. The front axle journal of the rotor extends forward from the fourth stage disc and is connected to the outer side of the third stage disc. In order to shorten the rotor length, 1~6 rotor blades are made of titanium alloy, 7~9 rotor blades are made of heat-resistant alloy, 1~5 rotor blades are made of titanium alloy, and 6~9 rotor blades are made of heat-resistant alloy. The inlet deflector and the 1 class deflector are both made of titanium alloy and installed on the front shell made of titanium alloy.
The combustion chamber is annular, with 28 dual-oil centrifugal nozzles, two ignition devices and semiconductor electric nozzles.
Turbine, high pressure turbine and low pressure turbine are all single stage. The HP turbine guide * * has 14 groups, and each group has 3 blades. The high-pressure turbine rotor blades * * have 90 blades without crowns. A shock absorber is installed on the tenon. The high-pressure turbine disk is connected with the front and rear shafts through bolts. After the two air flows in the combustion chamber are cooled by the external pipes, the cooling air flow of the high-pressure turbine blades is introduced by the guide blades. Low pressure turbine guide * * * has 1 1 group, and each group also has 3 blades. There are 90 rotor blades with crowns. The front and rear of the low-pressure turbine shaft are divided into three sections. The front and rear parts are made of heat-resistant stainless steel. The middle part is made of titanium alloy. These three parts are connected into a whole by a "fork" structure and radial pins. The blades of high and low pressure steam turbines are all air-cooled blades. The total cold air volume accounts for 65438+ of the internal air volume. Among them, 7.5% comes directly from the secondary air flow, which mainly cools the leading edge of the high-pressure turbine guide. 8.9% of the other air flow is taken out from the outer wall of the compressor and cooled by the air heat exchanger arranged in the outer bypass channel, which can reduce the temperature of the cooling air by125 ~ 2100 C. Among these air, 6.4% accounts for the internal flow and enters from the middle cavity of the high-pressure guide. 3.2% air is used to cool high pressure turbine rotor blades. Low-pressure turbine rotor blades are cooled by external duct air. The cooling gas is introduced into the interior through the support plate of the turbine rear shell, pressurized by the pump action of some radial inclined holes on the low-pressure turbine disk, and then enters the low-pressure turbine blades.
There is a mixer at the entrance of afterburner, which supplies oil in five zones. The fifth area is the start-up area of afterburner. It was ignited by a hot jet. The flame stabilizer has three V-shaped stabilizers and some radial flame transmission grooves. The anti-vibration measures are full-length anti-vibration net, and a large number of anti-vibration holes are opened at the inner tail cone.
There are 65,438+06 adjusting plates and sealing plates for the telescopic nozzle of the tail nozzle. The convergent nozzle is operated by 65,438+06 hydraulic actuators, while the divergent nozzle is fixed by an annular "belt" formed by 65,438+06 circumferential pneumatic actuators. With the change of pressure drop ratio of nozzle, the outlet cross-sectional area of nozzle changes due to pneumatic driving.
The basic part of the control system is a mechanical-hydraulic system, including main pump-main regulator, booster pump-regulator and nozzle control. It also has an analog electronic control device called integrated controller, which controls the limit value of the main working state of the engine and many other functions. When the electronic system fails, it will automatically switch to the mechanical-hydraulic system. It also has a multi-parameter monitoring system, an anti-surge system and a turbine cooling gas control system.