Foundation rotation platform suitable for simulating high-speed rotor

Abstract

The invention provides a basic rotation platform suitable for simulating a high-speed rotor, which comprises a platform body, the platform body comprises a flange plate, an inclined rib plate, a transverse rib plate and a longitudinal rib plate, the inclined rib plate, the transverse rib plate and the longitudinal rib plate are positioned around the flange plate, one end of the inclined rib plate is connected with the flange plate, and a double-rotor system is arranged above the platform body. The double-rotor system comprises a low-pressure compressor disc, a low-pressure rotor shaft, a high-pressure compressor disc, a high-pressure compressor disc, a high-pressure rotor shaft, a high-pressure turbine disc, an intermediate bearing and a low-pressure turbine disc which are sequentially arranged from front to back, and the low-pressure rotor shaft is fixedly connected to the platform body through a first rigid support, a second rigid support and a fourth rigid support. And the high-pressure rotor shaft is fixedly connected to the platform body by a third rigid support at the front end of the high-pressure compressor disc.

Description

Technical Field

[0001] The present invention belongs to the field of experimental verification of single / double rotor system dynamics in maneuvering flight, and in particular, relates to a basic rotating platform suitable for simulating high-speed rotors. Background Art

[0002] At present, the size of the basic rotating platform of the existing flight attitude turntable is generally small. The small-sized basic table surface will cause the experimental rotor model to be small, and ultimately the experimental results of the rotor experimental model under this small model will be far from the theoretical results due to experimental errors, processing accuracy and other reasons. If the platform size is directly enlarged, the platform mass will increase and exceed the carrying capacity of the drive motor and the platform shaft itself. If the platform is blindly reduced in weight based on the carrying capacity as a limiting condition, due to the weak constraint of the basic rotating platform, the structural stiffness of the basic rotating platform may be reduced, resulting in unknown risks in the rotor dynamics experiment, especially when the rotor speed is high, it is easy to cause harmonic resonance of the basic rotating platform. Therefore, the present invention designs a basic rotating platform for a high-speed rotor simulation test piece with a small mass and high stiffness that simultaneously meets the carrying capacity of the drive motor and the shaft and meets the requirements of the rotor dynamics experiment, and provides the principle process of designing this structure, as well as a simulated dual-rotor test piece on the basic rotating platform that can quantitatively reflect the results of the rotor dynamics theory calculation obtained by a dynamic similarity scaled model.

[0003] Therefore, the existing technology urgently needs to solve the problem of difficulty in designing the basic rotating platform for rotors with high similarity, the problem of unsatisfactory vibration signals caused by the basic structure in rotor dynamics experiments, and the integrated design of a rotor dynamics model with high similarity and the corresponding basic rotating platform. Summary of the invention

[0004] The purpose of the present invention is to address the deficiencies of the prior art and to provide a novel cross-seasonal artificial geothermal system and control method based on heat pipe technology.

[0005] The technical solution of the present invention is as follows:

[0006] A basic rotating platform suitable for simulating a high-speed rotor comprises a platform body, the platform body comprises a flange, inclined ribs located around the flange and connected to the flange at one end, transverse ribs and longitudinal ribs, a dual rotor system is arranged above the platform body, the dual rotor system comprises a low-pressure compressor disk, a low-pressure rotor shaft, a high-pressure compressor disk, a high-pressure compressor disk, a high-pressure rotor shaft, a high-pressure turbine disk, an intermediate bearing and a low-pressure turbine disk arranged in sequence from front to back, the low-pressure rotor shaft is fixedly connected to the platform body by a first rigid support, a second rigid support and a fourth rigid support, and the high-pressure rotor shaft is fixedly connected to the platform body by a third rigid support at the front end of the high-pressure compressor disk.

[0007] An outer frame is arranged at the outer edge of the platform body, a fixed frame is arranged at the center of the platform body, one end of the transverse rib plate and the longitudinal rib plate are connected to the fixed frame, and the other end is connected to the outer frame.

[0008] The beneficial effects of the present invention are as follows:

[0009] The dual-rotor-foundation rotating platform dynamic system test bench is less affected by the foundation rotating platform, and its own interference to the experimental signal is very weak and does not change with the rotor speed. From the perspective of modal analysis, it is concluded that the vibration of the foundation rotating platform itself does not pass through its own natural frequency, and the rotor excitation speed is not within the first-order mode of the foundation rotating platform. Therefore, during the experiment, this foundation rotating platform used to simulate the maneuverable flight state has better stability for the experimental signal than other thin plate foundations.

[0010] The basic rotating platform can be used not only in rotor dynamics experiments, but also in other experimental studies that require displacement excitation of the test piece through the basic rotating platform. The key point is that the basic rotating platform is different from the experimental requirements of the ordinary foundation being immovable because it has only a middle flange connection. The small stiffness leads to a lower first-order natural frequency, so it is easily affected by the excitation frequency of the actual test piece. At high frequencies, the vibration of the foundation itself is easily affected, and even the sensor drowns out the experimental signal with the vibration of the foundation. The present invention can solve this problem well by optimizing the design of the basic rotating platform from the perspective of dynamic experiments and modal principles. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Schematic diagram of the structure of a basic rotating platform suitable for simulating high-speed rotors.

[0012] Figure 2 It is a schematic diagram of the structure of the basic rotating platform without the simulated dual-rotor system tester.

[0013] Figure 3 The top view of the basic rotating platform.

[0014] Figure 4 This is the front cross-sectional view of the simulated dual-rotor system.

[0015] Figure 5 Campbell diagram for a dual-rotor system.

[0016] Figure 6 is the first-order mode shape of the basic rotating platform.

[0017] Figure 7 This is the stress distribution diagram of the basic rotating platform.

[0018] Figure numerals: 1 is a low-pressure compressor disk, 2 is a low-pressure rotor shaft, 3 is a high-pressure compressor disk, 4 is a high-pressure compressor disk, 5 is a high-pressure rotor shaft, 6 is a high-pressure turbine disk, 7 is an intermediate bearing, 8 is a low-pressure turbine disk, 9, 10, 11, 13 are the first, second, third and fourth rigid supports, and 12 is a platform body. DETAILED DESCRIPTION

[0019] In order to make the present invention more easily understood, the technical solution of the present invention is described in detail below in conjunction with specific embodiments and drawings, without limiting the protection scope of the present invention.

[0020] like Figure 1-4 The basic rotating platform suitable for simulating a high-speed rotor shown in the figure comprises a platform body 12, the platform body 12 comprises a flange 121, an inclined rib 122 located around the flange 121 and connected to the flange 121 at one end, a transverse rib 123 and a longitudinal rib 124, an outer frame is arranged at the outer edge of the platform body 12, a fixed frame is arranged at the center of the platform body, one end of the transverse rib 123 and the longitudinal rib 124 are connected to the fixed frame, and the other end is connected to the outer frame, and a dual rotor system is arranged above the platform body 12, the dual rotor system comprises a low-pressure compressor disk 1, a low-pressure rotor shaft 2, a high-pressure compressor disk 3, a high-pressure compressor disk 4, a high-pressure rotor shaft 5, a high-pressure turbine disk 6, an intermediate bearing 7 and a low-pressure turbine disk 8, which are arranged in sequence from front to back, the low-pressure rotor shaft 2 is fixedly connected to the platform body 12 by a first rigid support 9 / a second rigid support 10 and a fourth rigid support 13, and the high-pressure rotor shaft 5 is fixedly connected to the platform body 12 by a third rigid support 11 at the front end of the high-pressure compressor disk 3. The parameters of the above basic rotating platform are shown in Table 1.

[0021] Table 1

[0022]

[0023] Among them, λ i Represents the similarity ratio of parameter i, ρ, d, l, E represent the material density, diameter, length and elastic modulus of the shaft respectively, and m, Jp, ω, k represent the mass, polar moment of inertia, natural frequency and support stiffness respectively. Based on the same target critical speed of similar designs and taking into account the processing difficulty and processing accuracy of the actual structure after similar designs, the specific structure and minimum mass of the rotor system are determined.

[0024] Taking the existing dual rotors in the laboratory as an example, the high-pressure rotor is a 1-0-1 and the low-pressure rotor is a 0-2-1 support structure. The high and low-pressure rotors are connected by an intermediate bearing. After the dynamics are similar, the rationality of the model itself is verified through finite element model calculation and finite element software comparison.

[0025] Figure 5This is the Campbell diagram of the dual-rotor system, which shows the relationship between the speed and frequency in different operating modes of the dual-rotor system. Figure 6 is the first-order mode shape of the basic rotating platform. Figure 7 This is the stress distribution diagram of the basic rotating platform.

[0026] First, in the rotor dynamics analysis, in order to maintain the similarity with the original aircraft engine rotor in critical speed and vibration mode, the similarity design principle is applied to obtain the required parameters. Based on the Euler-Bernoulli beam theory, the rotor motion equation is expressed as:

[0027] The parameter design is mainly based on the second similarity theorem (π theorem), similar π group: π1=ωt,

[0028] After the specific structure and minimum mass of the rotor system are determined, the minimum length and maximum mass of the basic rotating platform are also determined.

[0029] According to the minimum length and maximum mass of the basic rotating platform, as well as the highest critical speed of the rotor, the value of the first-order natural frequency of the basic rotating platform is calculated to be greater than the highest critical speed of the rotor. Since the vibration is also severe within the half-power bandwidth, the first-order natural frequency of the basic rotating platform is determined to have a certain margin with the highest critical speed.

[0030] The basic rotating platforms of different structural forms are optimized in terms of small mass and high stiffness. For the structure serving as the basic platform, the first-order natural frequency is increased by increasing stiffness and reducing mass, which is usually done by adding ribs to the original foundation.

[0031] The thickness and depth of the ribs are discussed with the addition of ribs as the main optimization method, and the optimization results are verified through ANSYS Workbench to determine whether the current structure meets the requirements.

[0032] Taking the rotor being tested in the laboratory as an example, the maximum critical speed of the front and rear rotors is 8000rpm, and the modal analysis in ANSYS Workbench is used as the result for discussion. The rib form is continuously optimized iteratively to finally achieve the first-order natural frequency of the basic rotating platform below 170Hz.

[0033] Taking into account the rib structure and the structural form of the nut flange fixed to the rotating shaft, on the basis that the modal analysis meets the requirements, the statics method in the workbench is used again to perform strength analysis on the basic rotating platform. Taking the above-mentioned basic rotating platform as an example, the stress cloud diagram is observed by simulating the loading of 100kg force. The maximum stress is much lower than the material fatigue stress. Therefore, the basic rotating platform is in a safe state regardless of the dynamic or static force of the rotor test piece.

[0034] The above is only a preferred embodiment of the present invention, but the present invention is not limited to the above specific embodiments. For ordinary technicians in this field, several modifications and improvements can be made without departing from the creative concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A basic rotating platform suitable for simulating a high-speed rotor, characterized in that: The invention comprises a platform body, wherein the platform body comprises a flange, inclined ribs located around the flange and connected to the flange at one end, transverse ribs and longitudinal ribs; a dual-rotor system is arranged above the platform body, and the dual-rotor system comprises a low-pressure compressor disk, a low-pressure rotor shaft, a high-pressure compressor disk, a high-pressure compressor disk, a high-pressure rotor shaft, a high-pressure turbine disk, an intermediate bearing and a low-pressure turbine disk arranged in sequence from front to back; the low-pressure rotor shaft is fixedly connected to the platform body by a first rigid support, a second rigid support and a fourth rigid support; and the high-pressure rotor shaft is fixedly connected to the platform body by a third rigid support at the front end of the high-pressure compressor disk.

2. The basic rotating platform suitable for simulating a high-speed rotor according to claim 1 is characterized in that: An outer frame is arranged at the outer edge of the platform body, a fixed frame is arranged at the center of the platform body, one end of the transverse rib plate and the longitudinal rib plate are connected to the fixed frame, and the other end is connected to the outer frame.

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