A hydraulic loading device and method for paddle fan static-rotary integration

Abstract

The application relates to a kind of paddle fan static-rotary integrated hydraulic loading devices and methods, belong to the field of aero-engine load simulation.The device disclosed by the application comprises a universal ball (1), a hydraulic cylinder (2), a paddle fan test piece (3), a plurality of control oil paths, a hydraulic cylinder support frame (5), a force ring (6), a rotary joint (7), a plurality of supports and a hydraulic control system, the paddle fan test piece (3) is installed on a paddle fan wheel disc, the universal ball (1) and the force ring (6) are connected at the end of the piston rod of different hydraulic cylinders (2), a plurality of hydraulic cylinders (2) are installed on the hydraulic cylinder support frame (5), and the plurality of hydraulic cylinders (2) are connected with a plurality of control oil paths.The force transmission mode of the universal ball and the force ring without displacement constraint to the test piece is adopted, the static-rotary oil path connection between the hydraulic control system and the plurality of hydraulic cylinders (2) is realized by using the rotary joint (7), and the application has the advantages of small constraint force interference, good axial force, radial force, bending moment + torque independent loading and static-rotary integrated hydraulic loading.

Description

TECHNICAL FIELD

[0001] The application relates to a hydraulic loading device and method for integrating a fan blade in a static-rotary manner, and belongs to the field of load simulation of an aero-engine. BACKGROUND

[0002] Under static test conditions, simulated centrifugal load and aerodynamic load are applied to a fan blade test piece, so that the load bearing process of the real hub central piece bearing centrifugal force, axial force, bending moment and torque transmitted from the fan blade can be simulated at a lower economic cost, so as to verify whether the strength of the hub central piece meets the standard, and to test the load bearing capacity and dynamic response level of the variable pitch hydraulic system. Compared with the static test conditions, the load simulation under the rotary test conditions is closer to the actual load bearing process of the hub central piece and the variable pitch hydraulic system.

[0003] The hub central piece with a variable pitch mechanism is an important load bearing component, which needs to bear centrifugal force, axial force, bending moment and torque transmitted from the fan blade, and balance the load from the variable pitch hydraulic system. When the ground load simulation test of the hub central piece is carried out, the test piece bearing form and force transmission route are complex, there are many data measurement points, and the loading methods under the rotary and static conditions are not the same, which often becomes the biggest challenge of the test loading.

[0004] At present, the blade loading method in China is mostly independent separation of rotary and static loading, such as the invention patent with the title of "A hot spot simulation device and method for working blades" with the publication number CN113740370A, which proposes a stationary state down Centrifugal force loading scheme for pulling wire at the top of the blade, which will have interference of constraint force when the test piece deforms; such as the invention patent with the title of "A fatigue test device and method for loading alternating aerodynamic load on a wind turbine blade" with the authorized announcement number CN108760260B, which proposes a rotary state Distributed alternating aerodynamic load can be loaded on the test blade to more truly simulate the fatigue load suffered by the blade in the actual operation process, and the mean value and amplitude of the alternating aerodynamic load can be respectively realized by adjusting the rotating speed and pitch angle of the blade. The test scheme cannot be loaded under static conditions, and the test cost is high.

[0005] The load bearing form and force transmission route of the hub central part of the variable pitch mechanism of the propeller fan under static and rotating working conditions are often inconsistent, and the actual and theoretical deviations of the loading force and torque of the propeller fan simulation part are often caused by the strain displacement of the loading point when the propeller fan simulation part bears the load. How to design a loading device that can work stably and reliably under both static test conditions and rotating test conditions, truly and accurately simulate the aerodynamic load and centrifugal load received by the propeller fan simulation part, meet the requirements of maximum bending moment, maximum torque, maximum axial force and maximum radial force, and control the independent loading of various loads to the maximum extent according to the load spectrum, there is currently no good technical solution. SUMMARY

[0006] The purpose of the present application is to provide a propeller fan static-rotating integrated hydraulic loading device and method, aiming to provide a hydraulic loading device with little constraint force interference on the propeller fan test piece, good main vector + main moment independent loading, and at the same time meeting the static-rotating conditions.

[0007] To achieve the above purpose, the present application provides the following technical solutions:

[0008] A propeller fan static-rotating integrated hydraulic loading device, comprising: a universal ball, a hydraulic cylinder, a propeller fan test piece, a plurality of control oil paths, a hydraulic cylinder support frame, a force ring, a rotary joint, a plurality of supports and a hydraulic control system, the propeller fan test piece comprising a lower half cylindrical body, an upper half L-shaped body and a top boss, the propeller fan test piece is installed on the propeller variable pitch interface of the propeller wheel disc and driven to rotate by a rotating shaft, the universal ball and the force ring are respectively connected to the end of different hydraulic cylinder piston rods, the hydraulic cylinder is installed on the hydraulic cylinder support frame, a plurality of hydraulic cylinders are connected with a plurality of control oil paths, the plurality of control oil paths comprise eccentric force left and right cavity control oil paths, radial force left and right cavity control oil paths and axial force left and right cavity control oil paths, the rotary joint comprises a rotor end and a stator end, the rotor end is connected with a plurality of control oil paths, the stator end is connected with eccentric force inlet and outlet ports, radial force inlet and outlet ports and axial force inlet and outlet ports and connected to the hydraulic control system;

[0009] The propeller fan test piece will rotate around the midpoint of the blade root during the variable pitch process of the propeller variable pitch system, the L-shaped body and the top boss are respectively used for installing the hydraulic cylinders for applying radial centrifugal force load and the force application points, avoiding the constraint force caused by the top wire loading when the propeller fan test piece is strained, interfering with the actual and theoretical deviations of the axial force and the bending moment, the universal ball can apply pressure to the propeller fan test piece without position constraint during the variable pitch process, and the force ring can apply tension and pressure to the propeller fan test piece without position constraint during the variable pitch process;

[0010] The hydraulic loading device of the static-rotary integrated paddle fan is supported by a first support, a second support and a third support, a first bearing is installed on the first support, the first bearing is sleeved on the rotating shaft of the paddle fan wheel disc, the second bearing on the middle second support is installed between the rotor end and the stator end of the rotary joint, and is used for resisting the reaction force transmitted from the hydraulic cylinder through the hydraulic cylinder support frame, that is, plays the role of force transmission.

[0011] The hydraulic loading device of the static-rotary integrated paddle fan is supported by a first support, a second support and a third support, a first bearing is installed on the first support, the first bearing is sleeved on the rotating shaft of the paddle fan wheel disc, the second bearing on the middle second support is installed between the rotor end and the stator end of the rotary joint, and is used for resisting the reaction force transmitted from the hydraulic cylinder through the hydraulic cylinder support frame, that is, plays the role of force transmission.

[0012] Step 1: The actual aerodynamic load and centrifugal load of the paddle fan are calculated by numerical simulation solving method, and the load spectrum is obtained, and the specific technical means can be ANSYS, COMSOL and other commercial software, or self-programming to solve the equations of flow continuity, momentum conservation and energy conservation;

[0013] Step 2: Simplify the force system, select the blade root as the simplification center, and obtain the equivalent main vector and main moment: axial force, centrifugal force, torque and bending moment on the blade root;

[0014] Step 3: The force system minimum independent unit of the equivalent force system is determined by iterative calculation until the theoretical error of the resultant force and the resultant moment of the equivalent force system of the paddle fan test piece and the actual force system of the paddle fan is less than the set value in the static and rotating states, otherwise return to step 2;

[0015] Step 4: According to the load spectrum, load is applied to the paddle fan test piece to test whether the strength of the paddle hub central part meets the standard, and the load bearing capacity and dynamic response level of the variable pitch hydraulic system are tested;

[0016] The force system minimum independent unit refers to the smallest number of force sets that can independently load the axial force, centrifugal force, torque and bending moment of the paddle fan, the number of internal forces of the force set is the corresponding number of hydraulic cylinders, and the number also considers the feasibility of the load bearing form and the force transmission route of the paddle fan test piece and the coupling relationship in the force system. The paddle fan is a propeller paddle fan, because there is coupling between the torque and the bending moment of the paddle fan, three hydraulic cylinders are used, and according to the load spectrum, the axial force F3 passing through the blade root origin, the radial force F1 and the eccentric force F2 with lateral+radial offset on the blade root are applied, which can realize independent loading of the axial force, radial force and bending moment+torque of the paddle fan.

[0017] The hydraulic loading device of the static-rotary integrated propeller fan can exert axial force, radial force F1 and eccentric force F2 according to the load spectrum under static condition, and the universal ball installed at the end of the hydraulic cylinder piston rod is used to transmit force when simulating radial centrifugal force loading, so as to avoid the constraint force caused by the top tensile loading on the propeller fan test piece when the strain occurs, and to interfere with the actual and theoretical deviation of the axial force and bending moment; when simulating the axial aerodynamic load, the axial force F3 exerted by the force ring and the eccentric force F2 exerted by the universal ball are used to adjust the total axial force F while exerting torque and bending moment, and the variable pitch system with the pitch angle varying between-a° and b° is initially used, and due to the position limitation of the hydraulic cylinder exerting the eccentric force F2, the installation angle of the propeller fan test piece needs to be adjusted between-(a+b) / 2° and (a+b) / 2°, and corresponds to the pitch angle-a° and b°, and (a+b) / 2<90°, so that the eccentric force F2 can act on the propeller fan test piece.

[0018] The hydraulic loading device of the static-rotary integrated propeller fan is connected with the loading end of the hydraulic cylinder through the rotary joint under the rotating condition, so as to realize the loading under the rotating condition, and the load exerted under the rotating condition needs to deduct the centrifugal load, circumferential bending moment load and axial bending moment load exerted on the hub central part of the propeller fan test piece because of the rotation in the load spectrum.

[0019] The control method of the hydraulic loading device of the static-rotary integrated propeller fan is characterized by the following:

[0020] The hydraulic control system comprises a controller, an oil pump, a motor driving the oil pump, an overflow valve, a filter, an electro-hydraulic servo valve and a differential pressure sensor, the controller controls the motor to drive the oil pump to output hydraulic oil, the overflow valve ensures that the oil pressure does not exceed the allowable value, so as to prevent accidents caused by excessive oil pressure, the filter filters oil dirt, and finally the oil source is delivered to the electro-hydraulic servo valve, the controller controls the output current size to control the flow and pressure of the two-way output of the electro-hydraulic servo valve, and delivers them into the left and right cavities of the hydraulic cylinder, and the differential pressure sensor measures the oil pressure difference of the left and right cavities of the hydraulic cylinder, and calculates the force according to the piston area of the piston rod;

[0021] The application discloses a control method of a paddle fan static-rotary integrated hydraulic loading device, which is divided into a mechanical hydraulic oil source control method and a force servo control method.

[0022] Compared with the prior art, the application has the advantages that the universal ball and the force ring without displacement constraint are adopted to realize independent loading of axial force, radial force and bending moment+torque, the hydraulic loading scheme in static state and rotary state is completed through the multi-in and multi-out hydraulic rotary joint, the application solves the complex cross-linking problem of bearing forms and force transmission routes under static and rotary conditions, has the advantages of almost no constraint force interference on the paddle fan test piece, good independent loading of the main vector+main moment and the hydraulic loading under the static-rotary condition. BRIEF DESCRIPTION OF DRAWINGS

[0023] figure 1 It is a structural schematic view of the paddle fan static-rotary integrated hydraulic loading device.

[0024] figure 2 It is a schematic view of oil supply between the hydraulic control system and the loading mechanism of the integrated loading device.

[0025] figure 3 It is a schematic view of actual load analysis and force system equivalent simplification of the paddle fan.

[0026] In the figure, 1 is a universal ball, 2 is a hydraulic cylinder, 3 is a paddle fan test piece, 4 is an eccentric force left and right cavity control oil way, 5 is a hydraulic cylinder support frame, 6 is a force ring, 7 is a rotary joint, 71 is a rotor end, 72 is a stator end, 73 is an eccentric force inlet and outlet, 74 is a radial force inlet and outlet, 75 is an axial force inlet and outlet, 8 is a first support, 81 is a first bearing, 9 is a second support, 91 is a second bearing, 10 is a third support, 11 is a radial force left and right cavity control oil way, and 12 is an axial force left and right cavity control oil way. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0028] Please refer to figure 1 In the embodiments of the present application, a hydraulic loading device for propeller fan static-rotary integration comprises a universal ball 1, hydraulic cylinders 2, a propeller fan test piece 3, a plurality of control oil paths, a hydraulic cylinder support frame 5, a force ring 6, a rotary joint 7, a plurality of supports and a hydraulic control system. The propeller fan test piece 3 comprises a lower half cylindrical body 33, an upper half L-shaped body 32 and a top boss 31. The propeller fan test piece 3 is installed on a propeller fan variable pitch interface of a propeller fan wheel disc and is driven to rotate by a rotating shaft. The universal ball 1 and the force ring 6 are respectively connected to the end of different hydraulic cylinder 2 piston rods. The hydraulic cylinders 2 are installed on the hydraulic cylinder support frame 5. The plurality of hydraulic cylinders 2 are connected with the plurality of control oil paths. The plurality of control oil paths comprise eccentric force left and right cavity control oil paths 4, radial force left and right cavity control oil paths 11 and axial force left and right cavity control oil paths 12. The rotary joint 7 comprises a rotor end 71 and a stator end 72. The rotor end 71 is connected with the plurality of control oil paths. The stator end 72 is connected with eccentric force in and out oil ports 73, radial force in and out oil ports 74 and axial force in and out oil ports 75 and is connected to the hydraulic control system.

[0029] The propeller fan test piece 3 rotates around the midpoint of a blade root during the variable pitch process of a propeller fan variable pitch system. The L-shaped body 32 and the top boss 31 are respectively used for installing the hydraulic cylinders 2 for applying radial centrifugal force loads and force application points. The constraint force caused by the top tensile loading when the propeller fan test piece is strained is avoided. The actual and theoretical deviations of the axial force and the bending moment are interfered. The universal ball 1 can apply pressure to the propeller fan test piece without position constraint during the variable pitch process. The force ring 6 can apply tension and pressure to the propeller fan test piece without position constraint during the variable pitch process.

[0030] The hydraulic loading device is supported by a first support 8, a second support 9 and a third support 10. The first support 8 is installed with a first bearing 81. The first bearing 81 is sleeved on the rotating shaft of the propeller fan wheel disc. The second bearing 91 on the middle second support 9 is installed between the rotor end 71 and the stator end 72 of the rotary joint 7 and is used for resisting the reaction force transmitted from the hydraulic cylinders 2 through the hydraulic cylinder support frame 5, that is, plays a force transmission role.

[0031] Please refer to figure 2In this embodiment of the invention, a hydraulic loading device integrating stationary and rotating propellers is characterized in that the method for determining the number and loading form of the hydraulic cylinders 2 is as follows:

[0032] Step 1: Calculate the actual aerodynamic load and centrifugal load of the propeller through numerical simulation and obtain the load spectrum. The specific technical means can be commercial software such as ANSYS and COMSOL, or self-programming to solve equations such as flow continuity, momentum conservation and energy conservation.

[0033] Step 2: Simplify the force system by selecting the blade root as the simplification center to obtain the equivalent principal vector and principal moment: axial force, centrifugal force, torque and bending moment about the blade root;

[0034] Step 3: Iterate to determine the smallest independent element of the equivalent force system until the theoretical error of the resultant force and resultant moment of the equivalent force system and the actual force system of the propeller test piece is less than the set values ​​under static and rotating states; otherwise, return to step 2.

[0035] Step 4: Apply load to the propeller test piece according to the load spectrum to check whether the strength of the central component of the propeller hub meets the standard, and test the load-bearing capacity and dynamic response level of the variable pitch hydraulic system.

[0036] The minimum independent unit of the force system refers to the minimum number of force sets that can independently apply the axial force, centrifugal force, torque, and bending moment of the propeller fan. The number of forces within the force set is the number of hydraulic cylinders 2. This number also needs to consider the bearing form and force transmission route feasibility of the propeller fan test piece 3, as well as the coupling relationship within the force system. Taking a rear-mounted propeller fan as an example, since there is coupling between the propeller fan torque and bending moment, three hydraulic cylinders 2 are used to apply the axial force F3, radial force F1, and eccentric force F2 with lateral and radial offset to the blade root origin according to the load spectrum. This can achieve independent loading of the propeller fan axial force, radial force, and bending moment + torque. Among them, torque M1 = F2 × L1 (L1 is the circumferential distance from the hydraulic cylinder 2 applying the eccentric force F2 to the blade root O point), and bending moment M2 = F2 × L2 (L2 is the radial distance from the hydraulic cylinder 2 applying the eccentric force F2 to the blade root O point).

[0037] The hydraulic loading device of the paddle fan static-rotary integration can exert axial force, radial force F1 and eccentric force F2 under static condition according to load spectrum, when simulating radial centrifugal force loading, the universal ball installed at the end of the piston rod of the hydraulic cylinder 2 is used to transmit force, which avoids the constraint force caused by the top tensile loading when the strain of the paddle fan test piece occurs, and interferes with the actual and theoretical deviation of the axial force and bending moment; when simulating axial aerodynamic load, the axial force F3 exerted by the force ring 6 and the eccentric force F2 exerted by the universal ball 1 are used to realize the adjustment of the total axial force F while exerting torque and bending moment, the variable pitch system with the pitch angle changing between-10° and 90° is preliminarily used, due to the position limitation of the hydraulic cylinder exerting the eccentric force F2, the installation angle of the paddle fan test piece needs to be adjusted between-50° and 50°, and corresponds to the pitch angle-10° to 90°, and satisfies (a+b) / 2=50°<90°, so that the eccentric force F2 can act on the paddle fan test piece;

[0038] The hydraulic loading device of the paddle fan static-rotary integration is connected with the loading end of the hydraulic cylinder 2 through the rotary joint 7 under the rotating condition, so as to realize the loading under the rotating state, and the load exerted under the rotating state needs to deduct the centrifugal load, circumferential bending moment load and axial bending moment load exerted on the hub central piece due to the rotation of the paddle fan test piece in the load spectrum;

[0039] Please refer to figure 3 In the embodiment of the application, a control method of the hydraulic loading device of the paddle fan static-rotary integration is characterized by comprising the following processes:

[0040] The hydraulic control system comprises a controller, an oil pump, a motor driving the oil pump, an overflow valve, a filter, an electro-hydraulic servo valve and a differential pressure sensor, the controller controls the motor to drive the oil pump to output hydraulic oil, the overflow valve ensures that the oil pressure does not exceed the allowable value, so as to prevent accidents caused by excessively high oil pressure, the filter filters oil dirt, and finally the oil source is delivered to the electro-hydraulic servo valve, the controller controls the output current to control the flow and pressure of the two-way output of the electro-hydraulic servo valve, and delivers them into the left and right cavities of the hydraulic cylinder 2, and the differential pressure sensor measures the oil pressure difference of the left and right cavities of the hydraulic cylinder 2, and calculates the force according to the piston area of the piston rod;

[0041] A control method of a hydraulic loading device of a static-rotary integrated propeller fan, taking the structure of a post-thrust propeller fan, three hydraulic cylinders 2, and a loading device with an upper and lower symmetrical layout as an example, is divided into a mechanical hydraulic oil source control method and a force servo control method. The mechanical hydraulic oil source control method is as follows: the controller outputs a signal to the motor to start the oil pump, the oil pump outputs oil to the filter to remove impurities, the overflow valve prevents the oil pressure from being overloaded, and finally a multi-way hydraulic oil source with a certain pressure and flow rate is output. The force servo control method is as follows: the hydraulic oil source is transmitted to the electro-hydraulic servo valve, the controller receives the force instruction signal of the load spectrum, outputs a current signal of a certain size according to the control law, controls the electro-hydraulic servo valve to output two-way oil pressure meeting the requirements, and then the oil pressure is transmitted to the total of six oil chambers of the three hydraulic cylinders 2 of a static-rotary integrated hydraulic loading device of a propeller fan through a six-in and six-out rotary joint. Finally, the differential pressure sensor connected to the left and right chambers of the hydraulic cylinder 2 feeds back three differential pressure signals to the controller, the controller converts the differential pressure signals into the size of the force according to the piston area of the hydraulic cylinder 2, and the difference between the force instruction signal and the converted force is taken as the input of the control law to perform closed-loop control of the axial force F3, the radial force F1, and the eccentric force F2 force servo, so as to realize independent loading of the axial force, the radial force, and the bending moment + torque.

[0042] The present application is not limited to the above-mentioned embodiments. Based on the technical solutions disclosed in the present application, those skilled in the art can make some simple modifications, equivalent changes and modifications to some technical features without creative labor, which are all within the scope of the technical solutions of the present application.

Claims

1. A hydraulic loading device for a paddle fan static-rotary integration, comprising: Universal ball (1), hydraulic cylinder (2), paddle fan test piece (3), multiple control oil paths, hydraulic cylinder support frame (5), force ring (6), rotary joint (7), multiple supports and hydraulic control system, the paddle fan test piece (3) includes a lower half cylindrical body (33), an upper half L-shaped body (32) and a top boss (31), the paddle fan test piece (3) is installed on the paddle fan variable pitch interface of the paddle fan wheel disc and is driven to rotate by a rotating shaft, the universal ball (1) and the force ring (6) are connected at the ends of different hydraulic cylinder (2) piston rods respectively, the hydraulic cylinder (2) is installed on the hydraulic cylinder support frame (5), multiple hydraulic cylinders (2) are connected with multiple control oil paths, the multiple control oil paths include eccentric force left and right cavity control oil paths (4), radial force left and right cavity control oil paths (11) and axial force left and right cavity control oil paths (12), the rotary joint (7) includes a rotor end (71) and a stator end (72), the rotor end (71) is connected with multiple control oil paths, the stator end (72) is connected with eccentric force inlet and outlet ports (73), radial force inlet and outlet ports (74) and axial force inlet and outlet ports (75) and is connected to a hydraulic control system; The paddle fan test piece (3) rotates around the blade root midpoint during the variable pitch process of the paddle fan propeller variable pitch system, the L-shaped body (32) and the top boss (31) are respectively used for installing the hydraulic cylinder (2) for applying a radial centrifugal force load and a force application point, the universal ball (1) can apply a pressure without position constraint to the paddle fan test piece during the variable pitch process, and the force ring (6) can apply a tension and a pressure without position constraint to the paddle fan test piece during the variable pitch process. The paddle fan static-rotary integrated hydraulic loading device is supported by a first support (8), a second support (9) and a third support (10), the first support (8) is installed with a first bearing (81), the first bearing (81) is sleeved on a rotating shaft of the paddle fan wheel disc, a second bearing (91) on the middle second support (9) is installed between the rotor end (71) and the stator end (72) of the rotary joint (7) and is used for resisting a reaction force transmitted from the hydraulic cylinder (2) through the hydraulic cylinder support frame (5), that is, the second bearing (91) plays a force transmission role.

2. A hydraulic loading device of a paddle fan static-rotary integration type according to claim 1, wherein The number and loading form of the hydraulic cylinder (2) are determined by the following method: Step 1: the actual aerodynamic load and centrifugal load of the paddle fan are calculated by a numerical simulation solving method, and a load spectrum is obtained; Step 2: a force system is simplified, a blade root is selected as a simplified center, and equivalent main vectors and main moments, that is, axial forces, centrifugal forces, torques and bending moments on the blade root are obtained; Step 3: a force system minimum independent unit of the equivalent force system is determined by cyclic iteration until the theoretical error of the resultant force and the resultant moment of the equivalent force system of the paddle fan test piece and the actual force system of the paddle fan is less than a set value in the static and rotating states, otherwise, the step 2 is returned; Step 4: a load is applied to the paddle fan test piece according to the load spectrum so as to verify whether the strength of the paddle hub central part meets the standard and test the load bearing capacity and the dynamic response level of the variable pitch hydraulic system. The minimum independent unit of the force system refers to the minimum number of force sets for independently applying the axial force, centrifugal force, torque and bending moment of the propeller fan, the number of internal forces of the force set is the corresponding number of the hydraulic cylinder (2), and the number also considers the feasibility of the load bearing form and force transmission route of the propeller fan test piece (3) and the coupling relationship in the force system. The propeller fan is a propelling type propeller fan. Because there is coupling between the propeller fan torque and bending moment, three hydraulic cylinders (2) are used to apply the axial force F3, radial force F1 and eccentric force F2 with a lateral + radial offset distance to the blade root existing side according to the load spectrum, so as to realize the independent loading of the axial force, radial force and bending moment + torque of the propeller fan; The hydraulic loading device for static-rotary integration of the propeller fan can apply the axial force, radial force F1 and eccentric force F2 according to the load spectrum under the static condition. When the radial centrifugal force is simulated, the universal ball installed at the end of the piston rod of the hydraulic cylinder (2) is used for force transmission, so as to avoid the constraint force caused by the top wire loading when the propeller fan test piece is strained, and to interfere with the deviation between the actual and theoretical values of the axial force and bending moment. When the axial aerodynamic load is simulated, the axial force F3 applied by the force applying ring (6) and the eccentric force F2 applied by the universal ball (1) are used to adjust the total axial force F while the torque and bending moment are applied. The variable pitch system with the pitch angle changing between -a° and b° is initially used. Due to the position limitation of the hydraulic cylinder for applying the eccentric force F2, the installation angle of the propeller fan test piece needs to be adjusted between -(a+b) / 2° and (a+b) / 2°, and corresponds to the pitch angle -a° to b°. Moreover, (a+b) / 2<90° so that the eccentric force F2 can act on the propeller fan test piece. The hydraulic loading device for static-rotary integration of the propeller fan is connected with the loading end of the hydraulic cylinder (2) through the rotary joint (7) under the rotating condition, so as to realize the loading under the rotating state. The load applied under the rotating state needs to deduct the centrifugal load, axial force, circumferential bending moment load and axial bending moment load applied on the hub central piece of the propeller fan test piece due to rotation in the load spectrum.

3. The control method of a hydraulic loading device for a fan blade static-rotary integrated system according to claim 1, wherein As follows: The hydraulic control system comprises a controller, an oil pump, a motor for driving the oil pump, an overflow valve, a filter, an electro-hydraulic servo valve and a differential pressure sensor. The controller controls the motor to drive the oil pump to output hydraulic oil. The overflow valve ensures that the oil pressure does not exceed the allowable value, so as to prevent accidents caused by excessive oil pressure. The filter filters oil dirt. Finally, the oil source is delivered to the electro-hydraulic servo valve. The controller controls the output current to control the flow rate and pressure of the two outputs of the electro-hydraulic servo valve, and delivers them to the left and right cavities of the hydraulic cylinder (2). The differential pressure sensor measures the oil pressure difference between the left and right cavities of the hydraulic cylinder (2), and calculates the force according to the piston area of the piston rod. A kind of paddle fan static-rotary integrated hydraulic loading device control method is divided into mechanical hydraulic oil source control method and force servo control method, ① mechanical hydraulic oil source control method is: controller output signal is given to motor to start oil pump, oil pump exports oil to filter to remove impurity, overflow valve prevents oil pressure overload, finally exports multiple-way hydraulic oil source with certain pressure and flow;② force servo control method is: hydraulic oil source is sent to electro-hydraulic servo valve, controller receives the force instruction signal of load spectrum, according to control law output certain size of current signal, to control electro-hydraulic servo valve exports two-way oil pressure to meet the requirements, again through rotary joint is delivered to the left and right cavities of a kind of paddle fan static-rotary integrated hydraulic loading device hydraulic cylinder (2), finally connect the differential pressure sensor of the left and right cavities of hydraulic cylinder (2) and feedback pressure difference signal to controller, controller is converted into the size of force according to the piston area of hydraulic cylinder pressure difference signal, difference is made with force instruction signal in controller and as the input of control law, realize the force servo of gimbal ball (1) and force ring (6) installed in the end of piston rod precision closed-loop control.

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