阅读说明：本技术 一种可调节液舱制荡的方法 (Method capable of adjusting oscillation of liquid tank ) 是由 邹昶方 王晨屹 朱家演 缪泉明 袁晓楠 于 2021-09-07 设计创作，主要内容包括：本发明公开了一种可调节液舱制荡的方法,在液舱底部沿船长方向设置一块或多块间断分布的纵向隔板,沿横向设置多条滑轨,纵隔板与滑轨相连接实现沿船宽方向的运动。纵隔板通过弹簧和阻尼器与舱壁相连接,弹簧的劲度系数与阻尼器的阻尼系数可实时调整,根据对液舱的载液率以及外激励的监测,调整过弹簧与阻尼器的参数,使舱内液体的实际一阶共振频率远离外激励频率,防止发生共振；同时,当舱内液体发生晃荡时,在纵隔板、弹簧以及阻尼器的共同作用下,可吸收并耗散液体晃荡的能量,从而降低液舱壁面整体所受的冲击压力,并延长纵隔板的使用寿命,以降低由液舱晃荡带来的安全事故发生的概率,保证船舶行驶的安全。(The invention discloses a method for regulating oscillation of a liquid tank. The longitudinal partition plate is connected with the cabin wall through a spring and a damper, the stiffness coefficient of the spring and the damping coefficient of the damper can be adjusted in real time, and parameters of the spring and the damper are adjusted according to monitoring of the liquid carrying rate and external excitation of the liquid cabin, so that the actual first-order resonance frequency of liquid in the cabin is far away from the external excitation frequency, and resonance is prevented; meanwhile, when the liquid in the tank is shaken, the energy of the liquid shaking can be absorbed and dissipated under the combined action of the longitudinal partition plate, the spring and the damper, so that the impact pressure on the whole wall surface of the tank is reduced, the service life of the longitudinal partition plate is prolonged, the probability of safety accidents caused by the liquid tank shaking is reduced, and the running safety of the ship is ensured.)

1. A method for adjusting the oscillation of a liquid tank is characterized in that: the specific method comprises the following steps:

set up one or polylith discontinuous distribution's longitudinal baffle at the tank bottom along the length direction of the ship, be connected the lateral motion who realizes the longitudinal baffle through the slide rail with along the ship width direction, and be connected with the bulkhead through spring and attenuator, according to the monitoring to the carrier liquid rate of tank and external excitation, adjust the parameter of spring and attenuator, make the in-process that rocks at the tank, the external excitation frequency is kept away from to the actual resonance frequency of under-deck liquid, at the longitudinal baffle simultaneously, under the combined action of spring and attenuator, absorb and dissipate the energy that liquid rocked, thereby reduce the whole impact pressure who receives of tank wall.

2. The method of claim 1, wherein the method further comprises: the longitudinal partition plate is used as an oscillation suppressing original, and the height of the longitudinal partition plate is 10% -50% of the height of the liquid tank.

3. The method of claim 1, wherein the method further comprises: the longitudinal partition plates are whole plates of the length of the liquid tank or a plurality of sub-plates uniformly distributed along the length of the liquid tank, and the distribution number is 1-4.

4. The method of claim 1, wherein the method further comprises: the longitudinal partition plate is connected with the wall surface of the liquid tank through a gradually-increased spring with variable stiffness coefficient, and the stiffness coefficient range of the spring is adjusted according to the size of the liquid tank.

5. The method of claim 1, wherein the method further comprises: the damper is connected with the spring in parallel, the longitudinal partition plate is connected with the wall surface of the liquid tank, the damper is a damper with a variable damping coefficient, and the range of the damping coefficient is adjusted according to the size of the liquid tank.

Technical Field

The invention relates to the field of ship and ocean engineering, in particular to a method for adjusting oscillation of a liquid tank.

Background

The sloshing problem of the liquid tank is one of the hot problems in the scientific community and the engineering community, has been widely noticed and researched by researchers and engineers in various communities, and particularly along with the development and application of the LNG ship, the sloshing problem further highlights the importance of the sloshing problem in the aspects of ship design and ship safety. For the hull structure, the impact pressure caused by liquid sloshing has the largest influence on the wall surface when the liquid in the cabin resonates, so that how to reduce the impact pressure caused by the sloshing liquid and how to make the actual first-order natural frequency of the liquid in the cabin far away from the external excitation frequency becomes the key point for researching the sloshing problem and the ship design problem. At present, the common method for suppressing sloshing by changing the structural shape of the liquid tank can only reduce the local sloshing impact pressure, but the rest positions are likely to generate the phenomenon of pressure rise, and the method for arranging the fixed structure is likely to transfer the impact pressure of liquid to a component, so that the component is damaged, and safety accidents are generated. Meanwhile, the method of changing the structural shape of the liquid tank or setting a fixed component can only change the first-order natural frequency of the liquid in the tank from a fixed value to another fixed value and mostly reduce the first-order natural frequency, but with the change of the liquid carrying rate of the liquid tank, such as a tanker fuel tank, the first-order natural frequency of the liquid in the tank is reduced with the reduction of the liquid carrying rate, and the low-frequency external excitation carrying high energy is frequently generated in the actual working condition, so that the liquid in the tank is likely to resonate along with the common generation of a certain liquid carrying rate and the external excitation frequency. Therefore, the effect of the fixed structure and the member on changing the first-order natural frequency of the liquid in the cabin to achieve the oscillation damping effect is to be improved under certain working conditions. The method and the device for controlling the oscillation of the liquid tank are also to be improved, and a method for adjusting the oscillation of the liquid tank is provided.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a method for regulating oscillation of a liquid tank, which not only can absorb and dissipate the oscillation energy of liquid in the tank and reduce the oscillation impact force on a wall surface, but also can regulate the first-order resonance frequency of the liquid in the tank under different liquid carrying rates and prevent the first-order resonance frequency from resonating under the action of external excitation at different liquid carrying rates.

In order to achieve the purpose, the invention provides the following technical scheme: a method for adjusting the sloshing of a liquid tank comprises the following specific steps:

set up one or polylith discontinuous distribution's longitudinal baffle at the tank bottom along the length direction of the ship, be connected the lateral motion who realizes the longitudinal baffle through the slide rail with along the ship width direction, and be connected with the bulkhead through spring and attenuator, according to the monitoring to the carrier liquid rate of tank and external excitation, adjust the parameter of spring and attenuator, make the in-process that rocks at the tank, the external excitation frequency is kept away from to the actual resonance frequency of under-deck liquid, at the longitudinal baffle simultaneously, under the combined action of spring and attenuator, absorb and dissipate the energy that liquid rocked, thereby reduce the whole impact pressure who receives of tank wall.

As a preferable technical scheme of the invention, the longitudinal partition plate is used as an oscillation suppressing element, and the height of the longitudinal partition plate is 10% -50% of the height of the liquid tank.

As a preferred technical scheme of the invention, the longitudinal partition plates are whole plates of the length of the liquid tank or a plurality of sub-plates uniformly distributed along the length of the liquid tank, and the distribution number is 1-4.

In a preferred embodiment of the present invention, the longitudinal partition and the tank wall are connected by a gradual spring with a variable stiffness coefficient, and the range of the stiffness coefficient of the spring is adjusted according to the size of the tank.

As a preferred technical scheme of the invention, the damper is connected with the spring in parallel, the longitudinal partition plate is connected with the wall surface of the liquid tank, the damper is a damper with a variable damping coefficient, and the damping coefficient range is adjusted according to the size of the liquid tank.

The invention has the beneficial effects that: 1. the longitudinal partition plates are arranged along the length direction of the ship, so that vortexes are generated near the top ends of the longitudinal partition plates when sloshing fluid flows through the longitudinal partition plates, and the sloshing energy of the fluid is dissipated, so that the impact pressure of the fluid on the cabin wall can be well reduced when the liquid tank is at a medium-low loading rate;

2. the longitudinal partition plate can move along the width direction of the ship, and the spring and the damper are connected in parallel to connect the longitudinal partition plate and the cabin wall, so that the spring and the damper can absorb and gradually dissipate the shaking energy of the fluid when the liquid tank is shaken, and the impact pressure of the single fluid cabin wall is further reduced;

3. the spring and the damper can reduce the impact effect of fluid on the longitudinal partition plate caused by large-amplitude sudden excitation during medium and low loading, so that the strength requirement of the longitudinal partition plate can be reduced, and the service life of the longitudinal partition plate is prolonged;

4. the spring can absorb stored energy, the auxiliary damper can dissipate the oscillation energy and play a role in protecting the damper, and when the oscillation is severe, the spring can temporarily store the energy and simultaneously play a role in supporting the longitudinal partition plate together with the damper;

5. the stiffness coefficient of the spring and the damping coefficient of the damper can be changed in real time, so that the actual first-order natural frequency of the liquid in the tank can be changed, and the phenomenon that liquid resonance in the liquid tank is generated under the common occurrence of certain liquid carrying rate and external excitation frequency to generate huge impact pressure on a wall surface is avoided; the first-order natural frequency reduced by the fixed structure is prevented from being just coincided with the common high-energy low-frequency phenomenon in the actual working condition. The matching of different stiffness coefficients and damping coefficients can adjust the specific gravity of the spring and the damper in the oscillation action, so that the device can adapt to various different working conditions.

Drawings

FIG. 1 is a schematic view of an adjustable tank sloshing apparatus of the present invention;

FIG. 2 is a schematic view of a method of installing an adjustable stiffness spring system according to the present invention;

fig. 3 is a diagram of an incremental spring of the present invention.

In the figure: 1. hydraulic cylinder, 2, sealing ring, 3, inner cabin wall, 4, outer cabin wall, 5, incremental spring.

Detailed Description

The following detailed description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings, will make the advantages and features of the invention more readily understood by those skilled in the art, and thus will more clearly and distinctly define the scope of the invention.

Example (b): referring to fig. 1-3, the present invention provides a technical solution: a method for adjusting the sloshing of a liquid tank comprises the following specific steps:

set up one or polylith discontinuous distribution's longitudinal baffle at the tank bottom along the length direction of the ship, be connected the lateral motion who realizes the longitudinal baffle through the slide rail with along the ship width direction, and be connected with the bulkhead through spring and attenuator, according to the monitoring to the carrier liquid rate of tank and external excitation, adjust the parameter of spring and attenuator, make the in-process that rocks at the tank, the external excitation frequency is kept away from to the actual resonance frequency of under-deck liquid, at the longitudinal baffle simultaneously, under the combined action of spring and attenuator, absorb and dissipate the energy that liquid rocked, thereby reduce the whole impact pressure who receives of tank wall.

The longitudinal partition plate is used as an oscillation suppressing original, and the height of the longitudinal partition plate is 10% -50% of the height of the liquid tank.

The longitudinal partition plates are whole plates of the length of the liquid tank or a plurality of sub-plates uniformly distributed along the length of the liquid tank, and the distribution number is 1-4.

The longitudinal partition plate is connected with the wall surface of the liquid tank through a gradually-increased spring with variable stiffness coefficient, and the stiffness coefficient range of the spring is adjusted according to the size of the liquid tank.

The damper is connected with the spring in parallel, the longitudinal partition plate is connected with the wall surface of the liquid tank, the damper is a damper with a variable damping coefficient, and the range of the damping coefficient is adjusted according to the size of the liquid tank.

The working principle is as follows: a method for regulating liquid tank oscillation includes the specific steps of principle and design of oscillation making device, height selection of longitudinal partition plate, selection and installation of incremental spring 5 and selection of damper; as shown in fig. 1, the longitudinal partition plate capable of moving transversely is connected with the incremental spring 5 and the damper, so that the longitudinal partition plate can better absorb and dissipate the energy of the liquid and reduce the impact pressure of the liquid on the wall surface in the sloshing process of the liquid tank; the energy dissipation is mainly realized by the damper and the process that liquid generates vortex when flowing through the transverse partition plate, the spring can absorb the temporary storage energy, the effects of reducing the working load of the damper, protecting the damper and prolonging the service life of the damper are achieved, and meanwhile, the spring can reduce the impact effect of the liquid on the longitudinal partition plate under the excitation of large-amplitude sudden change during low loading; as shown in fig. 1, the progress coefficient k of the gradual-increase spring and the damping coefficient c of the damper are both variable parameters, so that the gradual-increase spring and the damper can be better matched to achieve a swinging effect, and the actual first-order natural frequency of the liquid in the tank can be adjusted in real time according to the carrying rate and the external excitation frequency of the liquid tank, so that the resonant frequency of the liquid is not lower at a medium-low loading rate and higher at a high loading rate, and a fixed value point is not available, so that the liquid resonates under the condition that a certain loading rate and the external excitation frequency occur together to generate huge wall surface impact pressure; since the wall impact pressure caused by sloshing of the tank is large during medium and low loading, and the resonance effect is relatively obvious, as shown in fig. 1, the height of the longitudinal partition plate is not more than half of the height of the tank and not less than one tenth of the height of the tank, the stiffness coefficient of the spring is variable by connecting the incremental spring and the longitudinal partition plate, as shown in fig. 2, one end of the incremental spring 5 is connected with the hydraulic cylinder 1, when the stiffness coefficient needs to be changed, the hydraulic cylinder 1 stretches and contracts to enable the incremental spring 5 to deform, one section of the incremental spring is compressed to be in contact with the front section of the hydraulic cylinder 1, so that the actual working turns of the incremental spring 5 are changed to change the stiffness coefficient, and the incremental spring 5 is selected as shown in fig. 3. As shown in figure 1, the damper and the spring are connected in parallel with the longitudinal partition plate, the damping coefficient of the damper can be changed, the electromagnetic damper can be selected to be realized by changing the electrical parameter of the damper or by other dampers, and the damper can change the actual natural frequency of the liquid in the cabin, absorb the oscillation energy and reduce the wall impact.

The above examples only show some embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.