A parameter design method for phase-shifting pipeline vibration absorber

Abstract

The present invention discloses a parameter design method for a phase-shifting pipeline vibration absorber, specifically comprising the following steps: collecting phase-shifting pipeline data parameters; calculating a vibration parameter characteristic matrix (w, A, F) using the collected data parameters; calculating an original parameter group (m2, k2) of the phase-shifting pipeline vibration absorber based on the vibration parameter characteristic matrix (w, A, F); randomly selecting an appropriate number of phase-shifting pipeline vibration absorber parameters from the original parameter group based on prior knowledge, and optimizing the pipeline vibration absorber parameters using a genetic algorithm to obtain optimal phase-shifting pipeline vibration absorber parameters. The present invention intelligently optimizes the design parameters to reduce the redundancy of the vibration absorber parameters, requiring fewer vibration absorber components to meet the diverse personalized vibration reduction requirements of phase-shifting pipelines.

Description

Technical Field

[0001] The present invention relates to the field of phase shifter pipeline vibration control, and in particular to a parameter design method for a phase shifter pipeline vibration absorber. Background Art

[0002] Phase condensers are crucial equipment for UHV and DC power transmission in my country's power grid. Their associated lubricating oil and cooling pipes provide crucial support for their safe and stable operation. However, in actual operation, due to limitations in the pipeline structure and the performance of their supports and hangers, the excitation forces of the phase condenser rotor can cause abnormal vibration in some pipes. This not only causes unnecessary fatigue stress in the pipes, reducing their service life, but can also, in severe cases, cause the supports and hangers to fail, seriously impacting the safe operation of the phase condensers and the health of personnel.

[0003] Most abnormal pipeline vibrations are caused by excitation frequencies close to the natural frequencies of the pipeline or system. In these cases, abnormal vibrations in the piping system can be reduced by using a vibration absorber. This dynamic vibration absorber is a simple spring-mass system that forms a two-degree-of-freedom system with the piping system to be dampened.

[0004] A vibration absorber is a mechanical device used to reduce or suppress unwanted vibrations. It consists of a mass block and an elastic element. Vibration absorbers are usually used in machines running at a constant speed. Because the vibration absorber is adjusted to a specific frequency when working and is only effective within a very narrow frequency band, personalized design parameters are required for different pipelines and different situations to ensure that the natural frequency of the final system is far away from the excitation frequency.

[0005] Current research on vibration absorbers is mostly focused on structural innovation. There is still a lack of corresponding guidance methods for the design of the most basic design parameters of vibration absorbers. If the pipeline parameters are designed in sequence according to the pipeline vibration characteristics, a large amount of redundancy in the vibration absorber design parameters will be caused, which will greatly cause waste of resources and increase the manufacturing cost of the vibration absorber. Summary of the Invention

[0006] In response to the problems existing in the prior art, the present invention provides a parameter design method for a phase-shifting pipeline vibration absorber, which can provide design parameters for the vibration absorber based on the actual pipeline characteristics and vibration characteristics. After intelligent optimization of the design parameters, the redundancy of the vibration absorber parameters can be reduced. Only fewer vibration absorber components are needed to meet the diverse personalized vibration reduction needs of phase-shifting pipelines, greatly reducing the design and manufacturing costs of the vibration absorber, while facilitating installation and use by staff.

[0007] To achieve the above object, the present invention provides the following technical solution: a parameter design method for a phase-shifting pipeline vibration absorber, specifically comprising the following steps:

[0008] Step 1: Collect the data parameters of the condenser pipeline;

[0009] Step 2: Calculate the vibration parameter characteristic matrix (w, A, F) using the collected data parameters, where w is the angular velocity of the condenser pipeline vibration state, F is the vibration stress of the condenser pipeline in all vibration states, and A is the maximum vibration amplitude of the condenser pipeline;

[0010] Step 3: Calculate the original parameter group (m2, k2) of the condenser pipeline vibration absorber based on the vibration parameter characteristic matrix (w, A, F), where m2 is the mass of the condenser pipeline vibration absorber and k2 is the spring stiffness of the condenser pipeline vibration absorber.

[0011] Step 4: According to the prior knowledge, randomly select a suitable number of phase-shifting pipeline vibration absorber parameters from the original parameter group (m2, k2), optimize the phase-shifting pipeline vibration absorber parameters through the genetic algorithm, and obtain the optimal phase-shifting pipeline vibration absorber parameters.

[0012] Furthermore, the data parameters include: the vibration frequency f of the phase shifter pipeline, the maximum peak speed v of the vibration max The measured outer diameter D, inner diameter d, pipe thickness t and vibrating section pipe length l of the condenser pipe are used, and the material density p and elastic modulus E are determined based on the condenser pipe material.

[0013] Furthermore,

[0014] w=2πf

[0015] A=v max / w

[0016] F=k eq ×A

[0017] Among them, v max is the maximum peak velocity of the condenser vibration, f is the vibration frequency of the condenser pipeline, k eq is the equivalent spring stiffness of the condenser pipe.

[0018] Furthermore, the equivalent spring stiffness k of the phase shifter pipeline is eq for:

[0019]

[0020] Where E is the elastic modulus of the CMOS pipeline material, l is the length of the CMOS pipeline vibrating part, I is the moment of inertia of the CMOS pipeline, d is the inner diameter of the condenser pipe, and D is the outer diameter of the condenser pipe.

[0021] Furthermore, the mass of the phase shifter pipeline vibration absorber is The spring stiffness of the phase shifter pipeline vibration absorber k2=w 2 m2, where l2 is the maximum displacement of the vibration absorber counterweight.

[0022] Furthermore, step 4 includes the following sub-steps:

[0023] Step 4.1, randomly select the phase-shifting pipeline vibration absorber parameters from the original parameter group (m2, k2) of the phase-shifting pipeline vibration absorber as chromosomes in the genetic algorithm;

[0024] Step 4.2: Determine whether the chromosome satisfies the optimization rule. If so, output the optimal solution for the parameters of the phase shifter pipeline vibration absorber. If not, proceed to step 4.3.

[0025] Step 4.3. During each evolution process, the fitness P is calculated and sorted from large to small. The fitness P is selected using a roulette wheel selection mechanism to evolve the corresponding parameter group of the phase shifter pipeline vibration absorber until the fitness P no longer changes. During the evolution process, the crossover probability of the parameter group of the phase shifter pipeline vibration absorber is 0.6, and the mutation probability is 0.2.

[0026] Furthermore, the optimization rule is:

[0027] (a) After installing the vibration absorber, the peak velocity allowed for the phase shifter pipeline is: Among them, C1 is the correction coefficient for compensating the concentrated mass effect between the characteristic spans of the condenser pipeline, C2 is the secondary stress index defined by the ASME Code, K2 is the local stress index, C3 is the correction coefficient considering the medium of the condenser pipeline, C4 is the correction coefficient for non-fixed ends and non-straight pipe spans, C5 is the correction coefficient when the span measurement frequency is different from the first-order natural frequency, β is the unit conversion coefficient, S el is the fatigue stress limit;

[0028] (b) The natural frequency after installing the vibration absorber differs from the excitation frequency by more than 10%;

[0029] (c) The maximum displacement X2 of the vibration absorber does not exceed the maximum displacement l2 of the preset vibration absorber counterweight.

[0030] Furthermore, the natural frequency after the vibration absorber is installed is Among them, k eq is the equivalent spring stiffness of the condenser pipe, m eq is the equivalent mass of the condenser pipeline.

[0031] Furthermore, the maximum displacement of the vibration absorber Among them, m eq is the equivalent mass of the condenser pipeline.

[0032] Furthermore, the fitness calculation process is specifically as follows:

[0033] P=C / number(F),

[0034] Where C is the number of vibration parameter feature matrices (w, A, F) that meet the optimization rules, and number(F) is the total number of vibration parameter feature matrices (w, A, F).

[0035] Compared with existing technologies, the present invention has the following advantages: The parameter design method for a phase-shifting pipeline vibration absorber of the present invention determines the phase-shifting pipeline vibration state through experimental methods and modal analysis. Based on this vibration state, the vibration absorber parameters are obtained and the vibration parameter characteristic matrix is ​​calculated. This allows the designed vibration absorber to simultaneously meet the vibration reduction requirements of multiple pipelines, multiple locations, and various vibration characteristics with less equipment, while also meeting the requirements of diversity and personalization. This fills a gap in the design of vibration absorbers for phase-shifting pipelines, a type of piping system operating in high-excitation environments. The vibration absorber obtained by this method has the characteristics of low redundancy, low cost, and high efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic diagram of the vibration mode of the lubricating oil inlet pipe of the condenser rotor;

[0037] Figure 2 This is a flow chart of the parameter design method of the phase shifter pipeline vibration absorber of the present invention. DETAILED DESCRIPTION

[0038] The present invention is further illustrated below with reference to the accompanying drawings. It should be understood that this specific embodiment is only used for the present invention and does not limit the scope of use of the present invention. After reading the present invention, modifications of various equivalent forms of the present invention made by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0039] like Figure 1 This is a schematic diagram of the vibration mode of the phase shifter rotor lubricating oil inlet pipe, where 1 to 11 are the pipe support and hanger positions, and (1) to (14) are the positions with the largest vibrations. After testing, the abnormal vibration frequencies f are 50 Hz and 100 Hz, respectively, and the maximum vibration speeds are 179.6 mm / s, 277 mm / s, 127 mm / s, and 108 mm / s. If the above parameters are used directly for vibration absorber design, 14 different vibration absorbers need to be designed, which greatly increases the manufacturing cost of the vibration absorber.

[0040] like Figure 2This is a flow chart of a parameter design method for a phase shifter pipeline vibration absorber according to the present invention. The parameter design method for a phase shifter pipeline vibration absorber specifically includes the following steps:

[0041] Step 1: Collect the data parameters of the condenser pipeline through experiments or modal analysis; the data parameters in the present invention include: the vibration frequency f of the condenser pipeline, the maximum peak velocity v of the vibration max The measured outer diameter D, inner diameter d, pipe thickness t and vibrating section pipe length l of the condenser pipe are used, and the material density p and elastic modulus E are determined based on the condenser pipe material.

[0042] Step 2: Calculate the vibration parameter characteristic matrix (w, A, F) using the collected data parameters to provide raw data for vibration absorber parameter calculation and can be used for subsequent fitness calculation. The calculation process of the vibration parameter characteristic matrix (w, A, F) in the present invention is specifically as follows:

[0043] w=2πf

[0044] A=v max / w

[0045] F=k eq ×A

[0046] Where w is the angular velocity of the condenser pipeline in the vibration state, F is the vibration stress of the condenser pipeline in all vibration states, A is the maximum vibration amplitude of the condenser pipeline, v max is the maximum peak velocity of the condenser vibration, F is the vibration stress of the vibration state, k eq is the equivalent spring stiffness of the condenser pipe, E is the elastic modulus of the condenser pipeline material, l is the length of the condenser pipeline vibrating part, I is the moment of inertia of the condenser pipeline, d is the inner diameter of the condenser pipe, and D is the outer diameter of the condenser pipe.

[0047] Step 3: Calculate the original parameter group (m2, k2) of the phase shifter pipeline vibration absorber based on the vibration parameter characteristic matrix (w, A, F). This original parameter group can be used to select the initial chromosome in the subsequent genetic algorithm and serve as the parameter selection boundary for crossover and mutation. Among them, m2 is the mass of the phase shifter pipeline vibration absorber, l2 is the maximum displacement of the vibration absorber counterweight, k2 is the spring stiffness of the phase shifter pipeline vibration absorber, k2=w 2 m2.

[0048] Step 4: Based on prior knowledge, randomly select a suitable number of CMOS pipeline vibration absorber parameters from the original parameter group (m2, k2), and optimize the CMOS pipeline vibration absorber parameters using a genetic algorithm to obtain the optimal CMOS pipeline vibration absorber parameters. This method has the advantages of high adaptability and is not prone to falling into local optimality. It specifically includes the following sub-steps:

[0049] Step 4.1, randomly select the phase-shifting pipeline vibration absorber parameters from the original parameter group (m2, k2) of the phase-shifting pipeline vibration absorber as chromosomes in the genetic algorithm;

[0050] Step 4.2: Determine whether the chromosome satisfies the optimization rule. If so, output the optimal solution for the parameters of the phase shifter pipeline vibration absorber. If not, proceed to step 4.3.

[0051] Step 4.3. In each evolutionary process, calculate the fitness P = C / number(F), and sort the fitness P from large to small. Use the roulette wheel selection mechanism to evolve the corresponding parameter group of the phase-shifting pipeline vibration absorber until the fitness P no longer changes; in the evolutionary process, the crossover probability of the parameter group of the phase-shifting pipeline vibration absorber is 0.6, that is, the partial mapping crossover method is used to exchange the information of the two chromosomes; the mutation probability is 0.2, that is, a random value is taken between the extreme values ​​of the original vibration absorber parameter library as the mutation of the individual information, where C is the number of vibration parameter characteristic matrices (w, A, F) that meet the optimization rules, and number(F) is the total number of vibration parameter characteristic matrices (w, A, F).

[0052] The optimization rules in the present invention are:

[0053] (a) After installing the vibration absorber, the peak velocity allowed for the phase shifter pipeline is: Among them, C1 is the correction coefficient for compensating the influence of concentrated mass between the characteristic spans of the condenser pipeline, C2 is the secondary stress index defined by the ASME Code, K2 is the local stress index, C3 is the correction coefficient for considering the medium of the condenser pipeline, which is taken as 1.414; C4 is the correction coefficient for non-fixed ends and non-straight pipe spans, which is 1.0 for straight span sections with fixed ends, 1.33 for cantilevers and simply supported beams, 0.74 for equal-arm Z-bend pipes, and 0.83 for equal-arm U-bend structures. A conservative value of 0.7 is used for evaluation; C5 is the correction coefficient when the span measurement frequency is different from the first-order natural frequency, β is the unit conversion coefficient, which is taken as 13.4 mm / s / MPa; S el is the fatigue stress limit, which is 93.7MPa for stainless steel and 48MPa for carbon steel;

[0054] (b) The natural frequency after the vibration absorber is installed has a difference of more than 10% from the excitation frequency; the natural frequency after the vibration absorber is installed in the present invention Among them, keq is the equivalent spring stiffness of the condenser pipe, m eq is the equivalent mass of the condenser pipeline, m is the mass of the tunable phase shifter pipeline. The volume of the tunable phase shifter pipeline is calculated by the length of the vibrating portion of the pipeline l and the thickness of the tunable phase shifter pipeline t. The mass of the tunable phase shifter pipeline is calculated by the density of the material of the tunable phase shifter pipeline.

[0055] (c) The maximum displacement X2 of the vibration absorber does not exceed the maximum displacement l2 of the preset vibration absorber counterweight; the maximum displacement of the vibration absorber in the present invention

[0056] Based on the above optimization rules, the vibration reduction effect and adaptation range of each set of vibration absorber parameters can be evaluated, thereby arranging the calculation of the fitness P.

[0057] After optimizing the parameters of the vibration absorber using the parameter design method of the phase shifter pipeline vibration absorber of the present invention, it is used for Figure 1 The vibration absorber design parameters are significantly reduced, requiring only absorber masses m2 of 0.6069 kg and 12.8324 kg, and spring stiffnesses k2 of 8.8248e+0.5 N / m and 1.9078e+0.5 N / m, to meet the vibration reduction requirements of the phase shifter pipeline. This invention uses experimental methods and modal analysis to determine the vibration state of the phase shifter pipeline, derives vibration absorber parameters based on this vibration state, and calculates the vibration parameter characteristic matrix. This design allows the designed vibration absorber to simultaneously meet the vibration reduction requirements of multiple pipelines, multiple locations, and various vibration characteristics with less equipment, while also meeting both diverse and personalized requirements.

[0058] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions based on the principles of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A parameter design method for a phase-shifting pipeline vibration absorber, characterized in that: The specific steps include: Step 1: Collect the data parameters of the condenser pipeline; Step 2: Calculate the vibration parameter characteristic matrix (w, A, F) using the collected data parameters, where w is the angular velocity of the condenser pipeline vibration state, F is the vibration stress of the condenser pipeline in all vibration states, and A is the maximum vibration amplitude of the condenser pipeline; Step 3: Calculate the original parameter group (m2, k2) of the condenser pipeline vibration absorber based on the vibration parameter characteristic matrix (w, A, F), where m2 is the mass of the condenser pipeline vibration absorber and k2 is the spring stiffness of the condenser pipeline vibration absorber. Step 4: Randomly select a suitable number of phase-shifting pipeline vibration absorber parameters from the original parameter group (m2, k2) based on prior knowledge, and optimize the phase-shifting pipeline vibration absorber parameters through genetic algorithm to obtain the optimal phase-shifting pipeline vibration absorber parameters; including the following sub-steps: Step 4.1, randomly select the phase-shifting pipeline vibration absorber parameters from the original parameter group (m2, k2) of the phase-shifting pipeline vibration absorber as chromosomes in the genetic algorithm; Step 4.2: Determine whether the chromosome satisfies the optimization rule. If so, output the optimal solution for the parameters of the phase shifter pipeline vibration absorber. If not, proceed to step 4.

3. The optimization rules are: (a) After installing the vibration absorber, the peak velocity allowed for the phase shifter pipeline is: Among them, C1 is the correction coefficient for compensating the concentrated mass effect between the characteristic spans of the condenser pipeline, C2 is the secondary stress index defined by the ASME Code, K2 is the local stress index, C3 is the correction coefficient considering the medium of the condenser pipeline, C4 is the correction coefficient for non-fixed ends and non-straight pipe spans, C5 is the correction coefficient when the span measurement frequency is different from the first-order natural frequency, β is the unit conversion coefficient, S el is the fatigue stress limit; (b) The natural frequency after installing the vibration absorber differs from the excitation frequency by more than 10%; (c) The maximum displacement X2 of the vibration absorber does not exceed the maximum displacement l2 of the preset vibration absorber counterweight; Step 4.

3. During each evolution process, the fitness P is calculated and sorted from large to small. The fitness P is selected using a roulette wheel selection mechanism to evolve the corresponding parameter group of the phase shifter pipeline vibration absorber until the fitness P no longer changes. During the evolution process, the crossover probability of the parameter group of the phase shifter pipeline vibration absorber is 0.6, and the mutation probability is 0.

2.

2. The parameter design method of the phase shifter pipeline vibration absorber according to claim 1 is characterized in that: The data parameters include: the vibration frequency f of the phase shifter pipeline, the maximum peak speed v of the vibration max The measured outer diameter D, inner diameter d, pipe thickness t and vibrating section pipe length l of the condenser pipe are used, and the material density p and elastic modulus E are determined based on the condenser pipe material.

3. The parameter design method of the phase-shifting pipeline vibration absorber according to claim 1 is characterized in that: w=2πf A=v max / w F=k eq ×A Among them, v max is the maximum peak velocity of the condenser vibration, f is the vibration frequency of the condenser pipeline, k eq is the equivalent spring stiffness of the condenser pipe.

4. The parameter design method of the phase-shifting pipeline vibration absorber according to claim 3 is characterized in that: The equivalent spring stiffness k of the phase shifter pipeline eq for: Where E is the elastic modulus of the CMOS pipeline material, l is the length of the CMOS pipeline vibrating part, I is the moment of inertia of the CMOS pipeline, d is the inner diameter of the condenser pipe, and D is the outer diameter of the condenser pipe.

5. The parameter design method of the phase-shifting pipeline vibration absorber according to claim 1 is characterized in that: The quality of the phase shifter pipeline vibration absorber The spring stiffness of the phase shifter pipeline vibration absorber k2=w 2 m2, where l2 is the maximum displacement of the vibration absorber counterweight.

6. The parameter design method of the phase-shifting pipeline vibration absorber according to claim 1 is characterized in that: The natural frequency after the vibration absorber is installed Among them, k eq is the equivalent spring stiffness of the condenser pipe, m eq is the equivalent mass of the condenser pipeline.

7. The parameter design method of the phase-shifting pipeline vibration absorber according to claim 1 is characterized in that: The maximum displacement of the vibration absorber Among them, m eq is the equivalent mass of the condenser pipeline.

8. The parameter design method of the phase-shifting pipeline vibration absorber according to claim 1 is characterized in that: The calculation process of the fitness is specifically as follows: P=C / number(F), Where C is the number of vibration parameter feature matrices (w, A, F) that meet the optimization rules, and number(F) is the total number of vibration parameter feature matrices (w, A, F).

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