A method for testing vibration isolation efficiency

Abstract

This application relates to a method for testing vibration isolation efficiency, used to evaluate the vibration isolation level of ship vibration isolation equipment. The ship includes a hull and a vibration source. The method for testing vibration isolation efficiency includes: obtaining a first vibration power W1 and a first vibration loss power W2 of the hull when the vibration isolation equipment is not installed; obtaining a second vibration power W3 and a second vibration loss power W4 of the hull after the vibration isolation equipment is installed; and obtaining the vibration isolation efficiency of the vibration isolation equipment based on the first vibration power W1, the first vibration loss power W2, the second vibration power W3, and the second vibration loss power W4. This application quantifies the vibration isolation effect of vibration isolation equipment, evaluates the vibration isolation level of vibration isolation equipment to vibration sources from an energy perspective, and provides more comprehensive test results. The numerical value of vibration isolation efficiency intuitively shows the quality of vibration isolation effect of vibration isolation equipment, which is highly convincing.

Description

A test method for vibration isolation efficiency Technical Field

[0001] This invention relates to the field of marine technology, and in particular to a method for testing vibration isolation efficiency. Background Technology

[0002] Ships at sea are constantly subjected to vibrations from equipment loads during navigation, such as engine vibrations. Under these loads, the hull structure is in a state of vibration for extended periods. Therefore, to mitigate the harmful effects of vibration on the hull structure, vibration isolation devices are typically installed on ships.

[0003] Currently, there are many methods for evaluating the vibration isolation effect of vibration isolation equipment, but they all measure single indicators such as displacement, velocity, and acceleration. For example, the vibration level of a ship after installing vibration isolation equipment is assessed by evaluating the vibration amplitude, vibration frequency, and acceleration of the hull. However, this evaluation method is too simplistic and cannot fully consider the interactions between hull components and between equipment systems and components. The conclusions drawn from this method regarding the vibration isolation level are not accurate enough and lack persuasiveness, thus hindering the optimization efficiency of ship vibration isolation. Summary of the Invention

[0004] Therefore, it is necessary to propose a test method for vibration isolation efficiency to more accurately determine the vibration isolation effect of the vibration isolation equipment, thereby improving the accuracy of vibration isolation level assessment and providing a more precise optimization direction for hull vibration isolation design and hull structure.

[0005] This application provides a method for testing vibration isolation efficiency to evaluate the vibration isolation level of ship vibration isolation equipment. The ship includes a hull and a vibration source. The method for testing vibration isolation efficiency includes:

[0006] The first vibration power W1 and the first vibration loss power W2 of the hull are obtained when the vibration isolation equipment is not installed on the ship.

[0007] The second vibration power W3 and the second vibration loss power W4 of the hull after the vibration isolation equipment is installed on the ship are obtained.

[0008] The vibration isolation efficiency of the vibration isolation device is obtained based on the first vibration power W1, the first vibration loss power W2, the second vibration power W3, and the second vibration loss power W4.

[0009] This application quantifies the vibration isolation effect of vibration isolation equipment, assessing its isolation level from an energy perspective. The magnitude of the vibration isolation efficiency directly indicates the effectiveness of the equipment in isolating the ship's hull. Compared to related technologies that rely on a single indicator, this application's method provides more comprehensive test results, directly demonstrating the effectiveness of the vibration isolation equipment through the vibration isolation efficiency value, thus offering greater persuasiveness. Furthermore, the vibration isolation efficiency testing method of this application can provide clear directions for optimizing ship vibration isolation based on the magnitude of the vibration efficiency, thereby contributing to improving the optimization efficiency of ship vibration isolation.

[0010] In some embodiments, the hull includes multiple decks and multiple ribs, and the step of obtaining the first vibration power W1 and the first vibration loss power W2 of the hull when the vibration isolation device is not installed includes:

[0011] When the vibration isolation equipment is not installed on the ship

[0012] The multiple decks are divided into multiple plate vibration domains;

[0013] The plurality of ribs are divided into a plurality of rib vibration domains;

[0014] The first sub-vibration power of each plate vibration domain is obtained sequentially;

[0015] The second sub-vibration power of each of the rib vibration domains is obtained sequentially;

[0016] The first sub-vibration loss power of each plate vibration domain is obtained sequentially;

[0017] The second sub-vibration loss power of each of the rib vibration domains is obtained sequentially;

[0018] The first sub-vibration power and the second sub-vibration power are linearly superimposed to obtain the first vibration power W1 of the hull;

[0019] The first sub-vibration loss power and the second sub-vibration loss power are linearly superimposed to obtain the first vibration loss power W2 of the hull.

[0020] In some embodiments, the step of sequentially acquiring the first sub-vibration power of each of the plate vibration domains includes:

[0021] Vibration parameters of each vibration domain of the plate are acquired sequentially using vibration sensors. The vibration parameters include amplitude and frequency.

[0022] The first sub-vibration power of each plate vibration domain is obtained according to the first formula, which is:

[0023]

[0024] Where, ρ a Let A be the surface density of the plate vibration domain, ω be the area of ​​the plate vibration domain, k be the vibration frequency of the plate vibration domain, and P1 be the first sub-vibration power of the plate vibration domain.

[0025] In some embodiments, the step of sequentially acquiring the second sub-vibration power of each of the rib vibration domains includes:

[0026] Vibration parameters of each rib vibration domain are acquired sequentially using vibration sensors. The vibration parameters include amplitude and frequency.

[0027] The second sub-vibration power of each rib vibration domain is obtained according to the second formula, which is:

[0028]

[0029] Where, ρ l Let L be the linear density of the rib vibration domain, L be the rib length of the rib vibration domain, ω be the vibration frequency of the rib vibration domain, k be the amplitude of the rib vibration domain, and P2 be the second sub-vibration power of the rib vibration domain.

[0030] In some embodiments, the step of sequentially obtaining the first sub-vibration loss power of each of the plate vibration domains includes:

[0031] The damping ratio of each plate vibration domain is obtained using the vibration attenuation method;

[0032] The first sub-vibration loss power of each plate vibration domain is obtained according to the fourth formula, which is:

[0033]

[0034] Where, ρ a Let A be the areal density of the plate vibration domain, ω be the area of ​​the plate vibration domain, k be the vibration frequency of the plate vibration domain, P4 be the first sub-vibration loss power of the plate vibration domain, and ξ be the damping ratio of the plate vibration domain.

[0035] In some embodiments, the step of sequentially obtaining the second sub-vibration loss power of each of the rib vibration domains includes:

[0036] The damping ratio of each rib vibration domain is obtained using the vibration attenuation method;

[0037] The second sub-vibration loss power of each rib vibration domain is obtained according to the fifth formula, which is:

[0038]

[0039] Where, ρ l Let L be the linear density of the rib vibration domain, L be the rib length of the rib vibration domain, ω be the vibration frequency of the rib vibration domain, k be the amplitude of the rib vibration domain, P5 be the second sub-vibration loss power of the rib vibration domain, and ξ be the damping ratio of the rib vibration domain.

[0040] In some embodiments, the hull includes multiple decks, multiple ribs, and concentrated mass points disposed on the decks or ribs. The step of obtaining the first vibration power W1 and the first vibration loss power W2 of the hull when the vibration isolation device is not installed includes:

[0041] When the vibration isolation equipment is not installed on the ship

[0042] The multiple decks are divided into multiple plate vibration domains;

[0043] The plurality of ribs are divided into a plurality of rib vibration domains;

[0044] The first sub-vibration power of each plate vibration domain is obtained sequentially;

[0045] The second sub-vibration power of each of the rib vibration domains is obtained sequentially;

[0046] Obtain the third sub-vibration power of the concentrated mass point;

[0047] The first sub-vibration loss power of each plate vibration domain is obtained sequentially;

[0048] The second sub-vibration loss power of each of the rib vibration domains is obtained sequentially;

[0049] The first sub-vibration power, the second sub-vibration power, and the third sub-vibration power are linearly superimposed to obtain the first vibration power W1 of the hull;

[0050] The first sub-vibration loss power and the second sub-vibration loss power are linearly superimposed to obtain the first vibration loss power W2 of the hull.

[0051] In some embodiments, the step of obtaining the third sub-vibration frequency of the concentrated mass point includes:

[0052] Vibration parameters of the concentrated mass point are obtained using a vibration sensor, the vibration parameters including amplitude and frequency;

[0053] The third sub-vibration power of the concentrated mass point is obtained according to the third formula, which is:

[0054]

[0055] Where m is the concentrated mass of the concentrated mass point, ω is the vibration frequency of the concentrated mass point, k is the amplitude of the concentrated mass point, and P3 is the third sub-vibration power of the concentrated mass point.

[0056] In some embodiments, the step of obtaining the second vibration power W3 and the second vibration loss power W4 of the hull after the vibration isolation device is installed on the ship includes:

[0057] When the ship is equipped with the vibration isolation device.

[0058] The fourth sub-vibration power of each plate vibration domain is obtained sequentially;

[0059] The fifth sub-vibration power of each of the rib vibration domains is obtained sequentially;

[0060] The third sub-vibration loss power of each plate vibration domain is obtained sequentially;

[0061] The fourth sub-vibration loss power of each of the rib vibration domains is obtained sequentially;

[0062] The fourth sub-vibration power and the fifth sub-vibration power are linearly superimposed to obtain the second vibration power W3 of the hull;

[0063] The third sub-vibration loss power and the fourth sub-vibration loss power are linearly superimposed to obtain the second vibration loss power W4 of the hull.

[0064] In some embodiments, the hull further includes concentrated mass points disposed on the deck or the ribs, and the step of obtaining the second vibration power W3 and the second vibration loss power W4 of the hull after the vibration isolation device is installed on the ship includes:

[0065] When the ship is equipped with the vibration isolation device.

[0066] The fourth sub-vibration power of each plate vibration domain is obtained sequentially;

[0067] The fifth sub-vibration power of each of the rib vibration domains is obtained sequentially;

[0068] Obtain the sixth sub-vibration power of the concentrated mass point;

[0069] The third sub-vibration loss power of each plate vibration domain is obtained sequentially;

[0070] The fourth sub-vibration loss power of each of the rib vibration domains is obtained sequentially;

[0071] The fourth sub-vibration power, the fifth sub-vibration power, and the sixth sub-vibration power are linearly superimposed to obtain the second vibration power W3 of the hull;

[0072] The third sub-vibration loss power and the fourth sub-vibration loss power are linearly superimposed to obtain the second vibration loss power W4 of the hull. Attached Figure Description

[0073] Figure 1 is a structural schematic diagram of a ship according to an embodiment of this application;

[0074] Figure 2 is a flowchart illustrating the method for testing vibration isolation efficiency according to an embodiment of this application;

[0075] Figure 3 is a schematic diagram of the deck and ribs in an embodiment of this application;

[0076] Figure 4 is a schematic diagram of the structure of the first sub-vibration power of the plate vibration domain in an embodiment of this application;

[0077] Figure 5 is a schematic diagram of the process for obtaining the first vibration power W1 and the first vibration loss power W2 of the ship hull when the ship is not equipped with vibration isolation equipment according to an embodiment of this application.

[0078] Figure 6 is a schematic diagram of the structure of the first sub-vibration loss power of the plate vibration domain according to an embodiment of this application;

[0079] Figure 7 is a structural schematic diagram of the first vibration power W1 of the hull in an embodiment of this application;

[0080] Figure 8 is a structural schematic diagram of the first vibration loss power W2 of the hull in an embodiment of this application. Detailed Implementation

[0081] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0082] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0083] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0084] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0085] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0086] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0087] Ships at sea are constantly subjected to vibrations from equipment loads during navigation, such as engine vibrations. Under these loads, the hull structure is in a state of vibration for extended periods. Therefore, to mitigate the harmful effects of vibration on the hull structure, vibration isolation devices are typically installed on ships.

[0088] Currently, there are many methods for evaluating the vibration isolation effect of vibration isolation equipment, but they all measure single indicators such as displacement, velocity, and acceleration. For example, the vibration level of a ship after installing vibration isolation equipment is assessed by evaluating the vibration amplitude, vibration frequency, and acceleration of the hull. However, this evaluation method is too simplistic and cannot fully consider the interactions between hull components and between equipment systems and components. The conclusions drawn from this method regarding the vibration isolation level are not accurate enough and lack persuasiveness, thus hindering the optimization efficiency of ship vibration isolation.

[0089] This application proposes a test method for vibration isolation efficiency, used to evaluate the vibration isolation level of the vibration isolation equipment on a ship 1. As shown in Figure 1, the ship 1 includes a hull 10 and a vibration source 20. The vibration source 20 can be, for example, an engine, pump, propeller, or other device. Vibration isolation equipment refers to a device that absorbs the vibration energy of the ship's vibration source 20, reduces vibration transmission, and thus reduces hull vibration. Typically, vibration isolation equipment is an elastic element, such as a spring isolator, rubber isolator, or air spring isolator. The vibration of the vibration source 20 can impede the comfort of the crew and may cause damage to the hull structure. By installing vibration isolation equipment on the ship 1, the impact of the vibration source 20 on the hull 10 can be reduced, thereby improving the hull's lifespan.

[0090] As shown in Figure 2, the test method for the vibration isolation efficiency of this application includes:

[0091] Obtain the first vibration power W1 and the first vibration loss power W2 of the hull 10 when the ship 1 is not equipped with vibration isolation equipment;

[0092] The second vibration power W3 and the second vibration loss power W4 of the hull 10 after the installation of vibration isolation equipment on the ship 1 are obtained.

[0093] The vibration isolation efficiency of the vibration isolation device is obtained based on the first vibration power W1, the first vibration loss power W2, the second vibration power W3, and the second vibration loss power W4.

[0094] In this application, the first vibration power W1 refers to the total vibration power of the hull 10 when no vibration isolation equipment is installed on the ship 1. The first vibration loss power W2 refers to the total vibration loss power of the hull 10 when no vibration isolation equipment is installed on the ship 1. The sum of the two is the total vibration power of the vibration source 20 of the ship 1 when no vibration isolation equipment is installed. The second vibration power W3 refers to the total vibration power of the hull after the installation of vibration isolation equipment on the ship 1. The second vibration loss power W4 refers to the total vibration loss power of the hull after the installation of vibration isolation equipment on the ship 1. The sum of the two is the total power of the vibration source 20 of the ship after the installation of vibration isolation equipment. This refers to the ratio of the total vibration power of the vibration source 20 after vibration isolation to the total vibration power of the vibration source 20 before vibration isolation. The magnitude of the ratio represents the quality of the vibration isolation effect of the vibration isolation equipment. The larger the ratio, the less vibration power the vibration isolation equipment absorbs, and the worse the vibration isolation effect; the smaller the ratio, the more vibration power the vibration isolation equipment absorbs, and the better the vibration isolation effect.

[0095] The vibration isolation efficiency test method of this application embodiment obtains the first vibration power W1 and the first vibration loss power W2 before the ship is equipped with vibration isolation equipment, and the second vibration power W3 and the second vibration loss power W4 after the ship is equipped with vibration isolation equipment, and then obtains the vibration isolation efficiency of the vibration isolation equipment. In other words, this application quantifies the vibration isolation effect of the vibration isolation equipment, assesses the vibration isolation level of the equipment for the vibration source 20 from an energy perspective, and directly indicates the quality of the vibration isolation effect of the equipment on the hull 10 through the value of the vibration isolation efficiency. Compared with the evaluation method of related technologies that uses a single index, the method of this application provides more comprehensive test results, directly indicating the quality of the vibration isolation effect of the equipment through the value of the vibration isolation efficiency, which is more convincing. In addition, the vibration isolation efficiency test method of this application can provide clear directions for the optimization of ship vibration isolation by measuring the magnitude of the vibration efficiency, thereby helping to improve the optimization efficiency of ship vibration isolation.

[0096] In some embodiments, as shown in FIG3, a partial structural schematic diagram of the hull 10 is presented. The hull 10 includes multiple decks 100 and multiple ribs 200. The decks 100 and ribs 200 constitute the basic structure of the hull 10.

[0097] As shown in Figure 5, the steps for obtaining the first vibration power W1 and the first vibration loss power W2 of the hull 10 when the ship 1 is not equipped with vibration isolation equipment include:

[0098] When ship 1 is not equipped with vibration isolation equipment

[0099] The multiple decks 100 are divided into multiple plate vibration domains 100a;

[0100] The multiple ribs 200 are divided into multiple rib vibration domains 200a;

[0101] The first sub-vibration power of each plate vibration domain 100a is obtained sequentially;

[0102] The second sub-vibration power of each rib vibration domain for 200a is obtained sequentially;

[0103] The first sub-vibration loss power of each plate vibration domain 100a is obtained sequentially;

[0104] The second sub-vibration loss power of each rib vibration domain for 200a is obtained sequentially;

[0105] The first sub-vibration power and the second sub-vibration power are linearly superimposed to obtain the first vibration power W1 of the hull 10;

[0106] The first sub-vibration loss power and the second sub-vibration loss power are linearly superimposed to obtain the first vibration loss power W2 of the hull 10.

[0107] This embodiment specifically illustrates a method for obtaining the first vibration power W1 and the first vibration loss power W2 of the hull 10 when the ship 1 is not equipped with vibration isolation equipment. Typically, as shown in Figure 3, the rib plate 200 includes transverse rib plates 210 and longitudinal rib plates 220, which form the main frame of the hull 10. A deck 100 is provided in the area enclosed by the transverse rib plates 210 and longitudinal rib plates 220. The deck 100 and the rib plate 200 are two types of components with different orientations on the hull 10. Furthermore, the deck 100 and the rib plate 200 are the main plate components of the hull 10, the main structures affected by the vibration source 20, and the boundaries between the deck 100 and the rib plate 200 are clear. Meanwhile, the vibration power of the entire hull 10 cannot be directly obtained. Therefore, in this embodiment, when no vibration isolation equipment is installed on the ship 1, the hull 10 is divided into grids according to the boundaries of the deck 100 and the rib plate 200, thereby dividing the entire hull 10 into multiple vibration domains, and then the vibration power and vibration loss power are calculated.

[0108] A vibration domain refers to the relationship between a vibration function or vibration parameter and time. In other words, within this region, the vibration relationship can be described by a mathematical function, thus obtaining the sub-vibration power of that region. Specifically, as shown in Figures 3 and 4, the boundary line between the ribs 200 and the deck 100 is used as the dividing line. The deck 100 enclosed by the transverse ribs 210 and longitudinal ribs 220 of the hull 10 is divided into a plate vibration domain 100a, and the transverse rib 210 or longitudinal rib 220 itself is divided into a rib vibration domain 200a. Thus, multiple decks 100 are divided into multiple plate vibration domains 100a, and multiple ribs 200 are divided into multiple rib vibration domains 200a. Therefore, by testing the sub-vibration power of each vibration domain and then linearly superimposing them, the first vibration power W1 of the entire hull 10 can be obtained. By testing the sub-vibration loss power of each vibration domain and then linearly superimposing them, the first vibration loss power W2 of the entire hull 10 can be obtained. This grid division method improves the ease and accuracy of calculating the total vibration power and total vibration loss power of the hull.

[0109] Further, the step of sequentially obtaining the first sub-vibration power of each plate vibration domain 100a includes:

[0110] Vibration parameters of each plate in a vibration domain of 100a were obtained sequentially using vibration sensors. The vibration parameters included amplitude and frequency.

[0111] The first sub-vibration power of each plate vibration domain 100a is obtained according to the first formula, which is:

[0112]

[0113] Where, ρ a Let ω be the surface density of the plate vibration domain 100a, A be the area of ​​the plate vibration domain 100a, ω be the vibration frequency of the plate vibration domain 100a, k be the amplitude of the plate vibration domain 100a, and P1 be the first sub-vibration power of the plate vibration domain 100a.

[0114] This embodiment specifically illustrates a method for obtaining the first sub-vibration power of multiple plate vibration domains 100a. Specifically, the first sub-vibration power P1 of each plate vibration domain 100a can be obtained through a first formula.

[0115] For example, as shown in Figure 4, in a specific embodiment, there are N plate vibration domains 100a, where N is an integer. The first sub-vibration power of the Nth plate vibration domain 100a is calculated as P1. N The surface density of the Nth plate vibration domain 100a is The area of ​​the vibration domain 100a of the Nth plate is A. N The vibration frequency of the Nth plate vibration domain 100a is ω.N The amplitude of the Nth plate vibration domain 100a is k N .

[0116] Then the first sub-vibration power P1 of the Nth plate vibration domain 100a N for:

[0117]

[0118] When the ship is not equipped with vibration isolation equipment, the total vibration power of the N plates in the vibration domain of 100a is W1. P1 Then the total vibration power W1 of the N plate vibration domains 100a P1 =11+12+13+14+15+…+P1 N In this way, the total vibration power W1 of the N plate vibration domains 100a is obtained. P1 The value of .

[0119] Further, the step of sequentially obtaining the first sub-vibration loss power of each plate vibration domain 100a includes:

[0120] The damping ratio of each plate in the vibration domain of 100a was obtained using the vibration attenuation method.

[0121] The first sub-vibration loss power of each plate vibration domain 100a is obtained according to the fourth formula, which is:

[0122]

[0123] Where, ρ a A, ω, and k are the known parameters of each plate vibration domain 100a mentioned above, and ω and k are the vibration parameters of plate vibration domain 100a measured by the vibration sensor mentioned above. P4 is the first sub-vibration loss power of plate vibration domain 100a, and ξ is the damping ratio of plate vibration domain 100a.

[0124] This embodiment illustrates the method for obtaining the first sub-vibration loss power P4 of each plate vibration domain 100a. The damping ratio ξ of each plate vibration domain 100a can be obtained through the vibration attenuation method. Vibration attenuation refers to the gradual decrease in amplitude of a structural component due to energy loss caused by damping when it is not subjected to external excitation. The damping ratio is the ratio of the damping coefficient to the critical damping coefficient, and it describes the magnitude of energy dissipation of a component during vibration.

[0125] As shown in Figure 6, as mentioned earlier, there are N vibration domains 100a, where N is an integer. The power loss of the first sub-vibration of the Nth vibration domain 100a is calculated to be P4. N The damping ratio of the Nth plate vibration domain 100a is ξ. N .

[0126] Then the first sub-vibration loss power P4 of the Nth plate vibration domain 100a N for:

[0127]

[0128] The total power loss of the vibration of N plates in a vibration domain of 100a is W2. P4 Then the total vibration loss power W2 of the N plate vibration domains 100a P4 =P41+P42+P43+P44+P45+…+P4 N Therefore, the total vibration loss power W2 of all plates in the vibration domain 100a of the hull 10 without vibration isolation equipment was obtained. P4 The value of .

[0129] In some embodiments, the step of sequentially obtaining the second sub-vibration power of each rib vibration domain 200a includes:

[0130] Vibration parameters, including amplitude and frequency, were obtained sequentially for each rib vibration domain 200a using vibration sensors.

[0131] The second sub-vibration power of each rib vibration domain over 200a is obtained according to the second formula, which is:

[0132]

[0133] Where, ρ l Let L be the linear density of the rib vibration domain 200a, L be the rib length of the rib vibration domain 200a, ω be the vibration frequency of the rib vibration domain 200a, k be the amplitude of the rib vibration domain 200a, and P2 be the second sub-vibration power of the rib vibration domain 200a.

[0134] This embodiment specifically illustrates the method for obtaining the second sub-vibration power P2 of each rib vibration domain 200a. Specifically, the second sub-vibration power P2 of each rib vibration domain 200a can be obtained through the second formula.

[0135] For example, as shown in Figure 7, in a specific embodiment, there are M rib vibration domains 200a, where M is an integer. The second sub-vibration power of the Mth rib vibration domain 200a is calculated to be P2. M The linear density of the vibration domain of the Mth rib, 200a, is The length of the rib in the Mth rib vibration domain 200a is L. M The vibration frequency of the Mth rib vibration domain 200a is ω. M .

[0136] Then the second sub-vibration power P2 of the Mth rib vibration domain 200a Mfor:

[0137]

[0138] The total vibration power of the M rib vibration domains over a period of 200 years is W1. P2 Then W1 P2 =P21+P22+P23+P24+P25+…+P2 M .

[0139] Thus, the total vibration power W1 of all rib vibration domains 200a of the hull 10 without vibration isolation equipment was obtained. P2 The value of .

[0140] Then the first vibration power W1 of the hull 10 is the total vibration power W1 of the N plate vibration domains 100a. P1 And the total vibration power W1 of the M rib vibration domains over 200a P2 The sum of . That is, W1 = W1 P1 +W1 P2 =P11+P12+P13+P14+P15+…+P1 N +P21+P22+P23+P24+P25+…+P2 M Thus, the value of the first vibration power W1 when the hull 10 is not equipped with vibration isolation equipment was obtained.

[0141] Further, the step of sequentially obtaining the second sub-vibration loss power of each rib vibration domain 200a includes:

[0142] The damping ratio of each rib's vibration domain over 200 years was obtained using the vibration attenuation method.

[0143] The second sub-vibration loss power of each rib vibration domain over 200a is obtained according to the fifth formula, which is:

[0144]

[0145] Where, ρ l L, ω, and k are the known parameters of each rib vibration domain 200a, and ω and k are the vibration parameters of the rib vibration domain 200a measured by the vibration sensor. P5 is the second sub-vibration loss power of the rib vibration domain 200a, and ξ is the damping ratio of the rib vibration domain 200a.

[0146] Using the damping ratio ξ of the rib vibration domain 200a and the fifth formula, the second sub-vibration loss power P5 of each rib vibration domain 200a can be obtained. As shown in Figure 8, as mentioned earlier, there are M rib vibration domains 200a, where M is an integer. The second sub-vibration loss power of the Mth rib vibration domain 200a is calculated to be P5. MThe damping ratio of the Mth rib vibration domain 200a is ξ. M .

[0147] Then the second sub-vibration loss power P5 of the Mth rib vibration domain 200a M for:

[0148]

[0149] The total power loss of the vibration in the M-rib vibration domain over 200 years is W2. P5 Then W2 P5 =P51+P52+P53+P54+P55+…+P5 M Therefore, the total vibration loss power W2 of all rib vibration domains 200a of the hull 10 without vibration isolation equipment was obtained. P5 The value of .

[0150] Then the first vibration loss power W2 of hull 10 is the total vibration loss power W2 of N plate vibration domains 100a. P4 And the total power W2 of vibration loss in the M rib vibration domains over 200 years P5 The sum, that is, W2 = W2 P4 +W2 P5 =P41+P42+P43+P44+P45+…+P4 N +P51+P52+P53+P54+P55+…+P5 M Thus, the value of the first vibration loss power W2 when the hull 10 is not equipped with vibration isolation equipment was obtained.

[0151] In this way, the first vibration power W1 and the first vibration loss power W2 when the hull 10 is not equipped with vibration isolation equipment can be obtained. The sum of the two is the total vibration power of the vibration source 20 when it is not isolated.

[0152] In other embodiments, the hull 10 further includes a concentrated mass point disposed on the deck 100 or the rib 200, and the step of obtaining the first vibration power W1 and the first vibration loss power W2 of the hull when the ship 1 is not equipped with vibration isolation equipment includes:

[0153] When the vibration isolation equipment is not installed on the ship

[0154] The multiple decks 100 are divided into multiple plate vibration domains 100a;

[0155] The multiple ribs 200 are divided into multiple rib vibration domains 200a;

[0156] The first sub-vibration power P1 of each plate vibration domain 100a is obtained sequentially;

[0157] The second sub-vibration power P2 of each rib vibration domain 200a is obtained sequentially;

[0158] Obtain the third sub-vibration power P3 of the concentrated mass point;

[0159] The first sub-vibration loss power P4 of each plate vibration domain 100a is obtained sequentially.

[0160] The second sub-vibration loss power P5 of each rib vibration domain 200a is obtained sequentially;

[0161] The first sub-vibration power P1, the second sub-vibration power P2, and the third sub-vibration power P3 are linearly superimposed to obtain the first vibration power W1 of the hull.

[0162] The first sub-vibration loss power P4 and the second sub-vibration loss power P5 are linearly superimposed to obtain the first vibration loss power W2 of the hull.

[0163] In this embodiment, the total vibration power of the hull 10, i.e., the first vibration power W1, also includes the third sub-vibration power P3 of the concentrated mass point. The concentrated mass point refers to a component with a certain mass installed on the deck 100 or the rib 200. The vibration generated by the vibration source 20 is transmitted not only to the hull 10, but also to various structural components installed on the hull 10. By including the first sub-vibration power P3 of the concentrated mass point in the total vibration power of the hull 10, it is beneficial to improve the calculation accuracy of the first vibration power W1 of the hull 10, thereby improving the accuracy of efficiency calculation and analysis accuracy.

[0164] It is easy to understand that the number of concentrated mass points can be one or more, depending on the actual number of concentrated mass points set on the hull 10. The methods for obtaining the first sub-vibration power P1, the second sub-vibration power P2, the first sub-vibration loss power P4, and the second sub-vibration loss power P5 have been explained above and will not be repeated here.

[0165] Further, the step of obtaining the third sub-vibration frequency P3 of the concentrated mass point includes:

[0166] Vibration parameters of a concentrated mass point are obtained using vibration sensors. These vibration parameters include amplitude and frequency.

[0167] The third sub-vibration power P3 of the concentrated mass point is obtained according to the third formula, which is:

[0168]

[0169] Where m is the mass of the lumped mass point, ω is the vibration frequency of the lumped mass point, k is the amplitude of the lumped mass point, and P3 is the third sub-vibration power of the lumped mass point.

[0170] This embodiment specifically illustrates the method for obtaining the third sub-vibration power of a concentrated mass point. Specifically, the third sub-vibration power P3 of each concentrated mass point (if there are multiple concentrated mass points) can be obtained through the third formula.

[0171] For example, in one specific embodiment, there are Q concentrated mass points, where Q is an integer. The third sub-vibration power of the Qth concentrated mass point is calculated as P3. Q The mass of the Qth mass point is m Q The vibration frequency of the Qth concentrated mass point is ω Q The amplitude of the Qth concentrated mass point is k Q .

[0172] Then the third sub-vibration power P3 of the Qth concentrated mass point Q for:

[0173]

[0174] The total vibration power of Q concentrated mass points is W1. P3 Then the total vibration power W1 of the Q concentrated mass points P3 =P31+P32+P33+P34+P35+…+P3 Q .

[0175] When there is a concentrated mass point on the hull 10, the first vibration power W1 when the hull 10 is not equipped with vibration isolation equipment is W1 = W1 P1 +W1 P2 +W1 P3 Thus, the value of the first vibration power W1 when the hull 10 is not equipped with vibration isolation equipment and has a concentrated mass point is obtained.

[0176] In some embodiments, the steps of obtaining the second vibration power W3 and the second vibration loss power W4 of the hull 10 after the installation of vibration isolation equipment on the ship 1 include:

[0177] When ship 1 is equipped with vibration isolation equipment

[0178] The fourth sub-vibration power of each plate vibration domain 100a is obtained sequentially;

[0179] The fifth sub-vibration power of each rib vibration domain for 200a is obtained sequentially;

[0180] The third sub-vibration loss power of each plate vibration domain 100a is obtained sequentially;

[0181] The fourth sub-vibration loss power of each rib vibration domain for 200a is obtained sequentially;

[0182] The fourth sub-vibration power and the fifth sub-vibration power are linearly superimposed to obtain the second vibration power W3 of the hull 10;

[0183] The third sub-vibration loss power and the fourth sub-vibration loss power are linearly superimposed to obtain the second vibration loss power W4 of the hull 10.

[0184] In this embodiment, when vibration isolation equipment is installed on the ship 1, the second vibration power W3 and the second vibration loss power W4 of the hull 10 after the vibration isolation equipment is installed are obtained through the aforementioned mesh division method. The methods for obtaining the fourth sub-vibration power and the third sub-vibration loss power of each plate vibration domain 100a, and the fifth sub-vibration power and the fourth sub-vibration loss power of each rib vibration domain 200a, are the same as those for obtaining the first sub-vibration power and the first sub-vibration loss power of each plate vibration domain 100a, and the second sub-vibration power and the second sub-vibration loss power of each rib vibration domain 200a. That is, when the ship 1 is not equipped with vibration isolation equipment, the first vibration power W1 and the first vibration loss power W2 of the hull 10 are obtained through mesh division. Then, when the ship 1 is equipped with vibration isolation equipment, the second vibration power W3 and the second vibration loss power W4 of the hull 10 are obtained through the same testing method. Since this testing method has been specifically described above, it will not be repeated here. This mesh division method is beneficial for improving the convenience and accuracy of calculating the total vibration power and the total vibration loss power of the hull 10.

[0185] By obtaining the second vibration power W3 and the second vibration loss power W4 of the hull 10 after the installation of the vibration isolation equipment through this grid division method, the vibration isolation efficiency of the vibration isolation equipment can be obtained, thereby enabling the evaluation of its vibration isolation level.

[0186] In other embodiments, the hull 10 further includes a concentrated mass point disposed on the deck 100 or the rib 200, and the step of obtaining the second vibration power W3 and the second vibration loss power W4 of the hull 10 after the installation of vibration isolation equipment on the ship 1 includes:

[0187] When ship 1 is equipped with vibration isolation equipment

[0188] The fourth sub-vibration power of each plate vibration domain 100a is obtained sequentially;

[0189] The fifth sub-vibration power of each rib vibration domain for 200a is obtained sequentially;

[0190] Obtain the sixth sub-vibration power of the concentrated mass point;

[0191] The third sub-vibration loss power of each plate vibration domain 100a is obtained sequentially;

[0192] The fourth sub-vibration loss power of each rib vibration domain for 200a is obtained sequentially;

[0193] The fourth sub-vibration power, the fifth sub-vibration power, and the sixth sub-vibration power are linearly superimposed to obtain the second vibration power W3 of the hull 10;

[0194] The third sub-vibration loss power and the fourth sub-vibration loss power are linearly superimposed to obtain the second vibration loss power W4 of the hull 10.

[0195] When the ship is equipped with vibration isolation equipment, this embodiment can obtain the sixth sub-vibration power of the concentrated mass point using the test method described above for ship 1 without vibration isolation equipment. Since the method for obtaining the vibration power of the concentrated mass point has already been specifically discussed above, it will not be repeated here.

[0196] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0197] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for testing vibration isolation efficiency, used to evaluate the vibration isolation level of ship vibration isolation equipment, said ship comprising a hull and a vibration source, characterized in that, The method for testing the vibration isolation efficiency includes: obtaining the first vibration power W1 and the first vibration loss power W2 of the hull when the ship is not equipped with the vibration isolation device; obtaining the second vibration power W3 and the second vibration loss power W4 of the hull after the ship is equipped with the vibration isolation device; and obtaining the vibration isolation efficiency of the vibration isolation device based on the first vibration power W1, the first vibration loss power W2, the second vibration power W3, and the second vibration loss power W4. The hull includes multiple decks and multiple ribs. The step of obtaining the first vibration power W1 and the first vibration loss power W2 of the hull when the vibration isolation equipment is not installed includes: when the vibration isolation equipment is not installed on the ship, dividing the multiple decks into multiple plate vibration domains; dividing the multiple ribs into multiple rib vibration domains; sequentially obtaining the first sub-vibration power of each plate vibration domain; sequentially obtaining the second sub-vibration power of each rib vibration domain; sequentially obtaining the first sub-vibration loss power of each plate vibration domain; sequentially obtaining the second sub-vibration loss power of each rib vibration domain; and sequentially calculating the first sub-vibration power and the second sub-vibration loss power. The first vibration power W1 of the hull is obtained by linearly superimposing the dynamic power; the first sub-vibration loss power and the second sub-vibration loss power are linearly superimposed to obtain the first vibration loss power W2 of the hull; the hull includes multiple decks, multiple ribs, and concentrated mass points disposed on the decks or ribs. The step of obtaining the first vibration power W1 and the first vibration loss power W2 of the hull when the vibration isolation device is not installed on the ship includes: when the vibration isolation device is not installed on the ship, dividing the multiple decks into multiple plate vibration domains; dividing the multiple ribs into multiple rib vibration domains; and sequentially obtaining the vibration power of each plate. The first sub-vibration power of the dynamic domain; the second sub-vibration power of each rib vibration domain is obtained sequentially; the third sub-vibration power of the concentrated mass point is obtained; the first sub-vibration loss power of each plate vibration domain is obtained sequentially; the second sub-vibration loss power of each rib vibration domain is obtained sequentially; the first sub-vibration power, the second sub-vibration power, and the third sub-vibration power are linearly superimposed to obtain the first vibration power W1 of the hull; the first sub-vibration loss power and the second sub-vibration loss power are linearly superimposed to obtain the first vibration loss power W2 of the hull; the second sub-vibration loss power of the hull after the vibration isolation equipment is installed is obtained. The steps of obtaining the vibration power W3 and the second vibration loss power W4 include: when the vibration isolation device is installed on the ship, sequentially obtaining the fourth sub-vibration power of each plate vibration domain; sequentially obtaining the fifth sub-vibration power of each rib vibration domain; sequentially obtaining the third sub-vibration loss power of each plate vibration domain; sequentially obtaining the fourth sub-vibration loss power of each rib vibration domain; linearly superimposing the fourth sub-vibration power and the fifth sub-vibration power to obtain the second vibration power W3 of the hull; and linearly superimposing the third sub-vibration loss power and the fourth sub-vibration loss power to obtain the second vibration loss power W4 of the hull.The hull also includes concentrated mass points disposed on the deck or the ribs. The step of obtaining the second vibration power W3 and the second vibration loss power W4 of the hull after the vibration isolation equipment is installed on the ship includes: when the vibration isolation equipment is installed on the ship, sequentially obtaining the fourth sub-vibration power of each plate vibration domain; sequentially obtaining the fifth sub-vibration power of each rib vibration domain; obtaining the sixth sub-vibration power of the concentrated mass point; sequentially obtaining the third sub-vibration loss power of each plate vibration domain; sequentially obtaining the fourth sub-vibration loss power of each rib vibration domain; linearly superimposing the fourth sub-vibration power, the fifth sub-vibration power, and the sixth sub-vibration power to obtain the second vibration power W3 of the hull; and linearly superimposing the third sub-vibration loss power and the fourth sub-vibration loss power to obtain the second vibration loss power W4 of the hull.

2. The method for testing vibration isolation efficiency according to claim 1, characterized in that, The step of sequentially obtaining the first sub-vibration power of each plate vibration domain includes: sequentially obtaining vibration parameters of each plate vibration domain using a vibration sensor, the vibration parameters including amplitude and frequency; and obtaining the first sub-vibration power of each plate vibration domain according to a first formula, the first formula being: ;in, Let A be the areal density of the plate vibration domain, and let A be the area of ​​the plate vibration domain. The vibration frequency of the plate vibration domain is given. P1 is the amplitude of the plate vibration domain and P1 is the first sub-vibration power of the plate vibration domain.

3. The method for testing vibration isolation efficiency according to claim 1, characterized in that, The step of sequentially obtaining the second sub-vibration power of each rib vibration domain includes: sequentially obtaining vibration parameters of each rib vibration domain using a vibration sensor, the vibration parameters including amplitude and frequency; and obtaining the second sub-vibration power of each rib vibration domain according to a second formula, the second formula being: ;in, Let L be the linear density of the rib vibration domain, and L be the rib length of the rib vibration domain. The vibration frequency of the rib vibration domain is given. P1 is the amplitude of the rib vibration domain, and P2 is the second sub-vibration power of the rib vibration domain.

4. The method for testing vibration isolation efficiency according to claim 2, characterized in that, The step of sequentially obtaining the first sub-vibration loss power of each plate vibration domain includes: obtaining the damping ratio of each plate vibration domain using the vibration attenuation method; and obtaining the first sub-vibration loss power of each plate vibration domain according to the fourth formula, wherein the fourth formula is: ;in, Let A be the areal density of the plate vibration domain, and let A be the area of ​​the plate vibration domain. The vibration frequency of the plate vibration domain is given. P4 represents the amplitude of the plate vibration domain, and P4 represents the first sub-vibration loss power of the plate vibration domain. is the damping ratio of the plate's vibration domain.

5. The method for testing vibration isolation efficiency according to claim 3, characterized in that, The step of sequentially obtaining the second sub-vibration loss power of each rib vibration domain includes: obtaining the damping ratio of each rib vibration domain using the vibration attenuation method; and obtaining the second sub-vibration loss power of each rib vibration domain according to the fifth formula, wherein the fifth formula is: ;in, Let L be the linear density of the rib vibration domain, and L be the rib length of the rib vibration domain. The vibration frequency of the rib vibration domain is given. P5 represents the amplitude of the rib vibration domain, and P5 represents the power loss of the second sub-vibration of the rib vibration domain. is the damping ratio of the vibration domain of the rib.

6. The method for testing vibration isolation efficiency according to claim 1, characterized in that, The step of obtaining the third sub-vibration power of the concentrated mass point includes: using a vibration sensor to obtain the vibration parameters of the concentrated mass point, the vibration parameters including amplitude and frequency; and obtaining the third sub-vibration power of the concentrated mass point according to a third formula, wherein the third formula is: ;in, The mass of the concentrated mass point is denoted as . The vibration frequency of the concentrated mass point. P3 is the amplitude of the concentrated mass point, and P3 is the third sub-vibration power of the concentrated mass point.

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