CN107895070A - A kind of orifice plate based on numerical simulation and hole plug division methods - Google Patents

A kind of orifice plate based on numerical simulation and hole plug division methods Download PDF

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CN107895070A
CN107895070A CN201711061447.XA CN201711061447A CN107895070A CN 107895070 A CN107895070 A CN 107895070A CN 201711061447 A CN201711061447 A CN 201711061447A CN 107895070 A CN107895070 A CN 107895070A
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hole
orifice plate
cavity length
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hole plug
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艾万政
王伟军
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Zhejiang Ocean University ZJOU
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Abstract

本发明涉及一种基于数值模拟的孔板与洞塞划分方法,选定空腔长为考察量,空腔长度小于消能孔厚度时为洞塞,空腔长度大于消能孔厚度时为孔板;确定影响空腔长度的因素,包括泄洪洞内水流的平均流速,水流密度,水流粘度,泄洪洞直径,消能孔直径;基于RNG k‑ε模型建立水流通过消能孔的数值模拟模型;对数值模拟结果进行分析拟合,确定空腔长度与相关因素的经验表达式,根据获得的空腔长度与消能孔厚度进行比较,划分孔板和洞塞。本发明的优点是建立了孔板和洞塞的划分标准,实现对孔板和洞塞的快速划分,提高孔板或者洞塞的消能效率,推广孔板或洞塞在高坝泄洪中的应用。

The invention relates to a method for dividing orifice plates and hole plugs based on numerical simulation. The length of the cavity is selected as the investigation quantity. When the cavity length is smaller than the thickness of the energy dissipation hole, it is a hole plug, and when the cavity length is greater than the thickness of the energy dissipation hole, it is a hole. plate; determine the factors that affect the length of the cavity, including the average flow velocity of the water flow in the spillway, the flow density, the viscosity of the flow, the diameter of the spillway, and the diameter of the energy dissipation hole; based on the RNG k‑ε model, the numerical simulation model of the flow through the energy dissipation hole is established ; Analyze and fit the numerical simulation results, determine the empirical expressions of the cavity length and related factors, and compare the obtained cavity length with the thickness of the energy dissipation hole to divide the orifice plate and the hole plug. The invention has the advantages of establishing the division standard of the orifice plate and the hole plug, realizing the rapid division of the orifice plate and the hole plug, improving the energy dissipation efficiency of the orifice plate or the hole plug, and popularizing the use of the orifice plate or the hole plug in the high dam flood discharge. application.

Description

一种基于数值模拟的孔板与洞塞划分方法A Numerical Simulation Based Orifice Plate and Hole Plug Division Method

技术领域technical field

本发明涉及水利工程技术领域,具体涉及一种基于数值模拟的孔板与洞塞划分方法。The invention relates to the technical field of water conservancy engineering, in particular to a method for dividing orifice plates and plugs based on numerical simulation.

背景技术Background technique

随着水电事业的快速发展,在水电工程项目中,高坝的使用越来越多,如此高的大坝,其下泄的水流具有巨大的能量,如何将高坝下泄的巨大能量消杀掉,以保护大坝及下游河道的安全,一直是摆在广大水电工作者面前的一大重要课题。With the rapid development of the hydropower industry, high dams are used more and more in hydropower engineering projects. Such a high dam has huge energy in the water flowing down. How to eliminate the huge energy released by the high dam? To protect the safety of dams and downstream rivers has always been an important issue facing the majority of hydropower workers.

孔板或洞塞在高坝泄洪中有重要应用,孔板或洞塞消能借助其特殊的体型,使得水流经过孔板时会产生突缩和突扩,从而形成强紊动和强剪切,以达到消能的目的。孔板或洞塞具有布置简单、经济、消能效率高、空化空蚀破坏较小等特点,在未来水电消能中有着重要的应用前景。Orifice plates or plugs have important applications in high dam flood discharge. With the help of their special shape, the energy dissipation of orifice plates or hole plugs will cause sudden contraction and expansion when the water flow passes through the orifice plate, thus forming strong turbulence and strong shear. , in order to achieve the purpose of energy dissipation. The orifice plate or hole plug has the characteristics of simple layout, economy, high energy dissipation efficiency, and small cavitation damage, and has an important application prospect in future hydropower energy dissipation.

孔板或洞塞均为消能孔,由于厚度不同,水流流过孔板时,水流只有一次突缩和突扩,而水流流过洞塞时,由于洞塞厚度大,水流有两次突缩和突扩,具体点说,空腔长度L小于消能孔厚度T时为洞塞,空腔长度L大于消能孔厚度T时为孔板,可见水流经过孔板或洞塞时流动规律是不一样的,因此在高坝消能设计时,尤其是采用多级消能孔结构时,要对孔板和洞塞进行划分,提高消能效率,但目前还没有人提出孔板与洞塞具体的划分标准。Both the orifice plate and the hole plug are energy-dissipating holes. Due to the difference in thickness, when the water flows through the orifice plate, the water flow has only one sudden contraction and expansion, but when the water flow passes through the hole plug, due to the large thickness of the hole plug, the water flow has two bursts. Constriction and sudden expansion, specifically speaking, when the cavity length L is less than the thickness T of the energy dissipation hole, it is a plug, and when the cavity length L is greater than the thickness T of the energy dissipation hole, it is an orifice plate. It can be seen that the flow law of the water flow through the orifice plate or the hole plug Therefore, in the energy dissipation design of high dams, especially when using multi-level energy dissipation hole structures, it is necessary to divide the orifice plate and the hole plug to improve the energy dissipation efficiency, but no one has proposed the hole plate and the hole plug specific classification criteria.

《中国农村水利水电》2009年第6期,文章名为“消能孔消能综述”中介绍了孔板和洞塞的几种实现方式、研究现状及实际应用,但是对孔板和洞塞只是概念上的区别描述,没有涉及孔板与洞塞具体的划分标准。"China Rural Water Conservancy and Hydropower" Issue 6, 2009, the article titled "Summary of Energy Dissipation Holes" introduced several implementation methods, research status and practical applications of orifice plates and hole plugs, but the orifice plates and hole plugs It is only a conceptual description of the difference, and does not involve specific standards for the division of orifice plates and hole plugs.

发明内容Contents of the invention

本发明的目的在于提供一种基于数值模拟的孔板与洞塞划分方法,以便能够实现对孔板和洞塞进行准确地划分,提高消能效率。The purpose of the present invention is to provide a method for dividing orifice plates and hole plugs based on numerical simulation, so as to realize accurate division of orifice plates and hole plugs and improve energy dissipation efficiency.

为了实现上述目的,本发明采用以下技术方案:In order to achieve the above object, the present invention adopts the following technical solutions:

一种基于数值模拟的孔板与洞塞划分方法,具体采用如下步骤:A method for dividing orifice plates and hole plugs based on numerical simulation, specifically adopting the following steps:

步骤一、选定空腔长度L为考察量,空腔长度L小于消能孔厚度T时为洞塞,空腔长度L大于消能孔厚度T时为孔板;Step 1. Select the cavity length L as the investigation quantity. When the cavity length L is less than the thickness T of the energy dissipation hole, it is a hole plug, and when the cavity length L is greater than the thickness T of the energy dissipation hole, it is an orifice plate;

步骤二、确定影响空腔长度L的因素,包括泄洪洞内水流的平均流速u,水流密度ρ,水流粘度μ,泄洪洞直径D,消能孔直径d;Step 2. Determine the factors affecting the length L of the cavity, including the average velocity u of the water flow in the spillway, the density of the flow ρ, the viscosity of the flow μ, the diameter of the spillway D, and the diameter of the energy dissipation hole d;

步骤三、基于RNG k-ε模型建立水流通过消能孔的数值模拟模型;Step 3. Based on the RNG k-ε model, a numerical simulation model of water flow through the energy dissipation hole is established;

步骤四、对数值模拟结果进行分析拟合,确定空腔长度L与相关因素的经验表达式,根据获得的空腔长度L与消能孔厚度T进行比较,划分孔板和洞塞。Step 4: Analyze and fit the numerical simulation results, determine the empirical expressions of the cavity length L and related factors, and compare the obtained cavity length L with the energy dissipation hole thickness T to divide the orifice plate and the hole plug.

作为优选,步骤二中确定影响空腔长度L的因素具体为通过量纲分析进一步得:L/D=f(β,Re),其中Re=uDρ/μ为雷诺数,β=d/D为孔径比。As a preference, determining the factors affecting the cavity length L in step 2 is further obtained through dimensional analysis: L/D=f(β, Re), wherein Re=uDρ/μ is the Reynolds number, and β=d/D is aperture ratio.

作为优选,步骤三中基于RNG k-ε模型建立水流通过消能孔的数值模拟模型具体为:As a preference, in step 3, based on the RNG k-ε model, the numerical simulation model for water flow through the energy dissipation hole is specifically:

(1)水流通过消能孔的数值模拟模型包括以下控制方程:(1) The numerical simulation model of water flow through energy dissipation holes includes the following control equations:

连续方程: Continuity equation:

动量守恒方程: Momentum Conservation Equation:

k-方程: k-equation:

ε-方程: ε-equation:

其中:xi(=x,y)为轴向及径向方向坐标,ui(=ux,uy)为轴向或径向方向的水流速度,ρ是流体的密度,p为压强,v为水流动力粘度,vt是涡粘度,vt=Cμ(k2/ε),k表示湍流动能,ε为湍流动能耗散率,Cμ=0.085,其他参数取值分别表示为η=Sk/ε,C1=1.42,ηo=4.377,λ=0.012,C2=1.68,αk=αε=1.39;Among them: x i (=x, y) is the axial and radial coordinates, u i (= u x , u y ) is the water velocity in the axial or radial direction, ρ is the density of the fluid, p is the pressure, v is the hydrodynamic viscosity, v t is the eddy viscosity, v t = C μ (k 2 /ε), k is the turbulent kinetic energy, ε is the dissipation rate of the turbulent kinetic energy, C μ = 0.085, and the values of other parameters are expressed as η=Sk/ε, C 1 =1.42, η o = 4.377, λ = 0.012, C 2 =1.68, α kε =1.39;

(2)水流通过消能孔的数值模拟模型的边界条件包括:入流边界、出流边界、对称轴边界以及壁面边界,各边界条件的处理方法是:入流边界条件有入流平均流速、湍流动能分布、湍流动能耗散率分布,它们的数学表达式分别为uin=u0,k=0.0144u0 2,ε=k1.5/(0.5R),其中u0为入口平均流速,R为泄洪洞半径;出流边界处理方法为假定出流得到充分发展;对称轴边界的处理方法是假定径向速度为0,而且各变量沿径向的梯度也被认为是0;壁面边界的处理方法为边界层流中采用了无滑移假定,壁面边界速度与边界节点的速度分量相等。(2) The boundary conditions of the numerical simulation model of water flow through energy dissipation holes include: inflow boundary, outflow boundary, symmetry axis boundary and wall boundary. , turbulent kinetic energy dissipation rate distribution, their mathematical expressions are u in =u 0 , k=0.0144u 0 2 , ε=k 1.5 /(0.5R), where u 0 is the average flow velocity at the inlet, and R is the spillway Radius; the treatment method of the outflow boundary is to assume that the outflow is fully developed; the treatment method of the symmetrical axis boundary is to assume that the radial velocity is 0, and the gradient of each variable along the radial direction is also considered to be 0; the treatment method of the wall boundary is boundary The no-slip assumption is adopted in laminar flow, and the wall boundary velocity is equal to the velocity component of the boundary node.

作为优选,步骤四中空腔长度L与相关因素的经验表达式具体为L/D=0.4427(d/D)-0.3538,其中d/D=0.4-0.8,Re>105As a preference, the empirical expression of the cavity length L and related factors in Step 4 is L/D=0.4427(d/D) -0.3538 , wherein d/D=0.4-0.8, Re>10 5 .

与现有技术相比,本发明的优点在于:基于RNG k-ε模型建立水流通过消能孔的数值模拟模型,依据模拟模型的结果,拟合数据得到了空腔长度与相关因素的经验表达式,建立了孔板和洞塞的划分标准,实现对孔板和洞塞的快速划分。Compared with the prior art, the present invention has the advantages of: based on the RNG k-ε model, the numerical simulation model of the water flow through the energy dissipation hole is established, and according to the results of the simulation model, the empirical expression of the cavity length and related factors is obtained by fitting the data According to the formula, the division standard of orifice plate and hole plug is established, and the rapid division of orifice plate and hole plug is realized.

附图说明Description of drawings

图1是本发明中水流经过孔板的流态示意图;Fig. 1 is the flow state schematic diagram of water flow through orifice among the present invention;

图2是本发明中水流经过洞塞的流态示意图;Fig. 2 is a flow schematic diagram of water flow through a hole plug in the present invention;

图3是本发明中L/D值随孔径比d/D变化关系图。Fig. 3 is a graph showing the relationship between the L/D value and the aperture ratio d/D in the present invention.

具体实施方式Detailed ways

下面结合附图和具体实施方式对本发明做进一步的描述。The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

如图1至图3中所示,一种基于数值模拟的孔板与洞塞划分方法,具体采用如下步骤:As shown in Fig. 1 to Fig. 3, a numerical simulation-based method for dividing an orifice plate and a hole plug uses the following steps:

步骤一、选定空腔长度L为考察量,空腔长度L小于消能孔厚度T时为洞塞,空腔长度L大于消能孔厚度T时为孔板;Step 1. Select the cavity length L as the investigation quantity. When the cavity length L is less than the thickness T of the energy dissipation hole, it is a hole plug, and when the cavity length L is greater than the thickness T of the energy dissipation hole, it is an orifice plate;

步骤二、确定影响空腔长度L的因素,包括泄洪洞内水流的平均流速u,水流密度ρ,水流粘度μ,泄洪洞直径D,消能孔直径d;Step 2. Determine the factors affecting the length L of the cavity, including the average velocity u of the water flow in the spillway, the density of the flow ρ, the viscosity of the flow μ, the diameter of the spillway D, and the diameter of the energy dissipation hole d;

步骤三、基于RNG k-ε模型建立水流通过消能孔的数值模拟模型;Step 3. Based on the RNG k-ε model, a numerical simulation model of water flow through the energy dissipation hole is established;

步骤四、对数值模拟结果进行分析拟合,确定空腔长度L与相关因素的经验表达式,根据获得的空腔长度L与消能孔厚度T进行比较,划分孔板和洞塞。Step 4: Analyze and fit the numerical simulation results, determine the empirical expressions of the cavity length L and related factors, and compare the obtained cavity length L with the energy dissipation hole thickness T to divide the orifice plate and the hole plug.

步骤二中确定影响空腔长度L的因素具体为通过量纲分析进一步得:L/D=f(β,Re),其中Re=uDρ/μ为雷诺数,β=d/D为孔径比。In step 2, the factors affecting the cavity length L are determined through dimensional analysis: L/D=f(β, Re), where Re=uDρ/μ is the Reynolds number, and β=d/D is the aperture ratio.

步骤三中基于RNG k-ε模型建立水流通过消能孔的数值模拟模型具体为:In Step 3, based on the RNG k-ε model, the numerical simulation model of water flow through the energy dissipation hole is established as follows:

(1)水流通过消能孔的数值模拟模型包括以下控制方程:(1) The numerical simulation model of water flow through energy dissipation holes includes the following control equations:

连续方程: Continuity equation:

动量守恒方程: Momentum Conservation Equation:

k-方程: k-equation:

ε-方程: ε-equation:

其中:xi(=x,y)为轴向及径向方向坐标,ui(=ux,uy)为轴向或径向方向的水流速度,ρ是流体的密度,p为压强,v为水流动力粘度,vt是涡粘度,vt=Cμ(k2/ε),k表示湍流动能,ε为湍流动能耗散率,Cμ=0.085,其他参数取值分别表示为η=Sk/ε,C1=1.42,ηo=4.377,λ=0.012,C2=1.68,αk=αε=1.39;Among them: x i (=x, y) is the axial and radial coordinates, u i (= u x , u y ) is the water velocity in the axial or radial direction, ρ is the density of the fluid, p is the pressure, v is the hydrodynamic viscosity, v t is the eddy viscosity, v t = C μ (k 2 /ε), k is the turbulent kinetic energy, ε is the dissipation rate of the turbulent kinetic energy, C μ = 0.085, and the values of other parameters are expressed as η=Sk/ε, C 1 =1.42, η o = 4.377, λ = 0.012, C 2 =1.68, α k =αε=1.39;

(2)水流通过消能孔的数值模拟模型的边界条件包括:入流边界、出流边界、对称轴边界以及壁面边界,各边界条件的处理方法是:入流边界条件有入流平均流速、湍流动能分布、湍流动能耗散率分布,它们的数学表达式分别为uin=u0,k=0.0144u0 2,ε=k1.5/(0.5R),其中u0为入口平均流速,R为泄洪洞半径;出流边界处理方法为假定出流得到充分发展;对称轴边界的处理方法是假定径向速度为0,而且各变量沿径向的梯度也被认为是0;壁面边界的处理方法为边界层流中采用了无滑移假定,壁面边界速度与边界节点的速度分量相等。(2) The boundary conditions of the numerical simulation model of water flow through energy dissipation holes include: inflow boundary, outflow boundary, symmetry axis boundary and wall boundary. , turbulent kinetic energy dissipation rate distribution, their mathematical expressions are u in =u 0 , k=0.0144u 0 2 , ε=k 1.5 /(0.5R), where u 0 is the average flow velocity at the inlet, and R is the spillway Radius; the treatment method of the outflow boundary is to assume that the outflow is fully developed; the treatment method of the symmetrical axis boundary is to assume that the radial velocity is 0, and the gradient of each variable along the radial direction is also considered to be 0; the treatment method of the wall boundary is boundary The no-slip assumption is adopted in laminar flow, and the wall boundary velocity is equal to the velocity component of the boundary node.

步骤四中空腔长度L与相关因素的经验表达式具体为L/D=0.4427(d/D)-0.3538,其中d/D=0.4-0.8,Re>105The empirical expression of the cavity length L and related factors in Step 4 is specifically L/D=0.4427(d/D) -0.3538 , where d/D=0.4-0.8, Re>10 5 .

将影响空腔长度L的因素,包括泄洪洞内水流的平均流速u,水流密度ρ,水流粘度μ,泄洪洞直径D,消能孔直径d进一步量纲分析,得到影响空腔长度L的主要因素分别是雷诺数Re和孔径比d/D,当孔径比固定为0.5不变时,变化雷诺数时,基于RNG k-ε模型进行计算,得到一组L/D值随雷诺数变化的数据,结果见表1。结果表明,当雷诺数大于0.9×105时,雷诺数对空腔长度的影响不大,几乎可忽略。The factors that affect the cavity length L include the average velocity u of the water in the flood tunnel, the current density ρ, the viscosity of the water μ, the diameter of the flood tunnel D, and the diameter of the energy dissipation hole d. The factors are the Reynolds number Re and the aperture ratio d/D. When the aperture ratio is fixed at 0.5 and the Reynolds number is changed, the calculation is based on the RNG k-ε model, and a set of data of L/D value changing with the Reynolds number is obtained. , the results are shown in Table 1. The results show that when the Reynolds number is greater than 0.9×10 5 , the Reynolds number has little effect on the cavity length, almost negligible.

表1孔径比d/D=0.5固定不变时,与L/D的值随雷诺数Re大小变化表Table 1 When the aperture ratio d/D=0.5 is fixed, the value of L/D changes with the Reynolds number Re

当雷诺数大于105,此时可忽略雷诺数对空腔长度的影响,变化孔径比的值,得到一组L/D值随孔径比变化的数据,通过获得的数据绘制如图3所示的L/D值随孔径比d/D变化关系图,曲线拟合图3,得到空腔长度与孔径比的经验表达式为L/D=0.4427(d/D)-0.3538,其中孔径比的适用范围为d/D=0.4-0.8,,雷诺数的适用范围为Re>105When the Reynolds number is greater than 10 5 , the influence of the Reynolds number on the cavity length can be ignored at this time, and the value of the aperture ratio can be changed to obtain a set of data on the change of the L/D value with the aperture ratio. The obtained data is plotted as shown in Figure 3 The relationship between the L/D value and the aperture ratio d/D is shown in Fig. 3, and the empirical expression of the cavity length and the aperture ratio is obtained as L/D=0.4427(d/D) -0.3538 , where the aperture ratio The applicable range is d/D=0.4-0.8, and the applicable range of Reynolds number is Re>10 5 .

根据已知的孔径比和泄洪洞直径,带入空腔长度与孔径比的经验表达式,可算出空腔长度,再将空腔长度与消能孔厚度进行比较,空腔长度小于消能孔厚度时为洞塞,空腔长度大于消能孔厚度时为孔板,实现对孔板或者洞塞的快速划分,提高孔板或者洞塞的消能效率,进一步推广孔板或洞塞在高坝泄洪中的应用。According to the known aperture ratio and the diameter of the spillway tunnel, the empirical expression of the cavity length and aperture ratio can be used to calculate the cavity length, and then the cavity length is compared with the energy dissipation hole thickness, and the cavity length is less than the energy dissipation hole When the thickness is thicker, it is a hole plug, and when the cavity length is greater than the thickness of the energy dissipation hole, it is an orifice plate, which realizes the rapid division of the orifice plate or hole plug, improves the energy dissipation efficiency of the orifice plate or hole plug, and further promotes the orifice plate or hole plug at high Application in dam flood discharge.

Claims (4)

1. a kind of orifice plate based on numerical simulation and hole plug division methods, it is characterized in that, a kind of orifice plate based on numerical simulation with Hole plug division methods specifically use following steps:
Step 1: selected cavity length L is investigation amount, cavity length L fills in when being less than energy dissipating hole thickness T for hole, and cavity length L is big It is orifice plate when the thickness T of energy dissipating hole;
Step 2: determine to influence cavity length L factor, including in flood discharging tunnel current mean flow rate u, jet density ρ, current Viscosity, mu, flood discharge hole dia D, energy dissipating bore dia d;
Step 3: numerical simulator of the current by energy dissipating hole is established based on RNG k- ε models;
Step 4: logarithm value analog result carries out analysis fitting, cavity length L and the empirical representation of correlative factor, root are determined According to the cavity length L of acquisition compared with the thickness T of energy dissipating hole, orifice plate and hole plug are divided.
2. a kind of orifice plate based on numerical simulation according to claim 1 and hole plug division methods, it is characterized in that, step 2 It is middle to determine that the factor for influenceing cavity length L further obtains specifically by dimensional analysis:L/D=f (β, Re), wherein Re=uD ρ/ μ is Reynolds number, and β=d/D is aperture ratio.
3. a kind of orifice plate based on numerical simulation according to claim 1 and hole plug division methods, it is characterized in that, step 3 In current established based on RNG k- ε models be specially by the numerical simulator in energy dissipating hole:
(1) current include following governing equation by the numerical simulator in energy dissipating hole:
Continuity equation:
Momentum conservation equation:
K- equations:
ε-equation:
Wherein:xi(=x, y) for axially and radially direction coordinate, ui(=ux, uy) for the water velocity in axially or radially direction, ρ It is the density of fluid, p is pressure, and v is flow dynamic viscosity, vtIt is vortex viscosity, vt=Cμ(k2/ ε), k represents Turbulent Kinetic, and ε is Dissipation turbulent kinetic energy, Cμ=0.085, other specification value is expressed asη=Sk/ ε, C1= 1.42ηo=4.377, λ=0.012,C2=1.68, αkε= 1.39;
(2) current are included by the boundary condition of the numerical simulator in energy dissipating hole:Become a mandarin border, Outlet boundary, symmetry axis side Boundary and wall border, the processing method of each boundary condition are:The boundary condition that becomes a mandarin becomes a mandarin mean flow rate, Turbulent Kinetic point Cloth, dissipation turbulent kinetic energy distribution, their mathematic(al) representation is respectively uin=u0, k=0.0144u0 2, ε=k1.5/ (0.5R), Wherein u0For entrance mean flow rate, R is flood discharging tunnel radius;Outlet boundary processing method is to assume that stream attains full development;It is right The processing method on axle border assumes that radial velocity is referred to as 0, and the gradient of each variable radially is also considered as 0;Wall side The processing method on boundary is to be employed in boundary layer flow without sliding it is assumed that the velocity component phase of wall boundary speed and boundary node Deng.
4. a kind of orifice plate based on numerical simulation according to claim 2 and hole plug division methods, it is characterized in that, step 4 Middle cavity length L and the empirical representation of correlative factor are specially L/D=0.4427 (d/D)-0.3538, wherein d/D=0.4- 0.8, Re > 105
CN201711061447.XA 2017-11-01 2017-11-01 A kind of orifice plate based on numerical simulation and hole plug division methods Pending CN107895070A (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101858069A (en) * 2010-06-23 2010-10-13 河海大学 A Discrimination Method for Flow State of Sudden Contraction and Expansion Energy Dissipator
CN104991992A (en) * 2015-06-01 2015-10-21 浙江海洋学院 Calculation method of hole plate water-flow pressure recovery length
CN105045987A (en) * 2015-07-06 2015-11-11 浙江海洋学院 Method for calculating relation of influence of thickness of pore plate on energy loss coefficient of pore plate

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101858069A (en) * 2010-06-23 2010-10-13 河海大学 A Discrimination Method for Flow State of Sudden Contraction and Expansion Energy Dissipator
CN104991992A (en) * 2015-06-01 2015-10-21 浙江海洋学院 Calculation method of hole plate water-flow pressure recovery length
CN105045987A (en) * 2015-07-06 2015-11-11 浙江海洋学院 Method for calculating relation of influence of thickness of pore plate on energy loss coefficient of pore plate

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
WU JIAN-HUA, AI WAN-ZHENG: "FLOWS THROUGH ENERGY DISSIPATERS WITH SUDDEN REDUCTION AND SUDDEN ENLARGEMENT FORMS", 《JOURNAL OF HYDRODYNAMICS》 *

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Application publication date: 20180410