A design optimization method of a new type of anti-erosion conical throttling valve

Abstract

The application provides a design optimization method of a new anti-erosion conical throttling valve, which simulates and analyzes an existing conical throttling valve and an optimized conical throttling valve in Workbench software, and the erosion condition in the pipeline of the conical throttling valve when the inlet flow rate is 20 m / s. The simulation result analysis shows that the internal erosion area of the anti-erosion conical throttling valve under the above conditions is obviously smaller than that of the existing conical throttling valve in the gas wellhead device. According to the internal velocity field distribution of the anti-erosion conical throttling valve, the internal velocity of the anti-erosion conical throttling valve is obviously higher than that of the existing conical throttling valve, and the inlet flow rate of the anti-erosion conical throttling valve directly affects the internal flow rate field distribution, so the anti-erosion throttling valve is analyzed under different inlet flow rates. The anti-erosion effect of the anti-erosion conical throttling valve is better than that of the existing conical throttling valve, and the internal fluid flow rate of the anti-erosion conical throttling valve is lower than that of the existing conical throttling valve.

Description

Technical Field

[0001] This invention belongs to the field of erosion technology of throttle valves, and particularly relates to a design optimization method for a novel anti-erosion conical throttle valve. Background Technology

[0002] A gas wellhead assembly is a pressure-bearing device used to control the wellhead pressure and flow rate of a natural gas well. It can also be used for various operations such as acid fracturing, water injection, and testing. It mainly consists of three parts: the casing head, the tubing head, and the wellhead tree. During natural gas extraction, the throttle valve in the wellhead assembly primarily functions as a flow cutoff and speed regulator, provides load resistance, and acts as a pressure buffer, maintaining pressure balance within the assembly. During drilling and production, the natural gas being extracted and transported contains solid particles and gravel. Over time, the throttle valve is subjected to erosion from the gas-solid two-phase flow, eventually leading to its failure.

[0003] The conical throttle valves in existing gas wellhead equipment suffer from erosion due to the presence of sand and gravel in the natural gas. The continuous scouring and impact of these materials causes erosion damage to the valve body, affecting the sealing performance of the wellhead equipment and leading to blowouts and well kicks. Therefore, mitigating the erosion of the throttle valve is a pressing technical problem that needs to be solved in current technology. Summary of the Invention

[0004] The purpose of this invention is to provide a novel design optimization method for an anti-erosion conical throttle valve to mitigate the erosion phenomenon of the throttle valve.

[0005] A novel design optimization method for an anti-erosion conical throttle valve includes the following steps:

[0006] S1: Design the structural parameters of the anti-erosion cone throttle valve based on the basic parameters of the cone throttle valve in the gas wellhead device of the valve design manual;

[0007] S2: Create simplified models of the 3D model of the conical throttle valve and the 3D model of the erosion-resistant conical throttle valve, and set material properties and mesh the simplified models in ANSYS Workbench:

[0008] S3: Import the two simplified models from step S2 into WorkbenchFluent software, and perform erosion simulation analysis on the two simplified models at an inlet flow velocity of 20m / s based on the erosion model.

[0009] S4: Import the simplified model of the anti-erosion conical throttle valve from step S2 into WorkbenchFluent software, and perform erosion simulation analysis on the anti-erosion conical throttle valve at different flow velocities than 20m / s based on the erosion model.

[0010] S5: Compare the erosion simulation analysis results in steps S3 and S4, and select the inlet flow velocity of the anti-erosion conical throttle valve.

[0011] Preferably, the erosion model formula in step S3 is:

[0012]

[0013] In the formula, R erosion - Wear rate per unit area of ​​the wall surface, kg / m 2 -s;

[0014] Nparticle - the number of colliding particles per unit area;

[0015] M P - Mass flow rate of colliding particles, kg / s;

[0016] c(d P - The shape function of particle size;

[0017] A face - Area of ​​the wall calculation unit, m 2 ;

[0018] f(θ1) - Impact angle function;

[0019] This is a particle relative function.

[0020] Preferably, the simulation analysis in step S3 is based on the turbulent kinetic energy k and the dissipation rate ε, specifically expressed as:

[0021]

[0022]

[0023]

[0024]

[0025]

[0026] G k One is the generation of turbulent kinetic energy due to the average velocity gradient;

[0027] G b One type of turbulent kinetic energy is generated due to the influence of buoyancy. For incompressible fluids, G b =0;

[0028] Y M The effect of compressible turbulent pulsating expansion on the total dissipation rate, for incompressible fluids, is given by Y. M =0;

[0029] μ t μ i μ j A turbulent viscosity coefficient;

[0030] ρ is the fluid density;

[0031] ε is the dissipation rate of turbulent pulsating kinetic energy;

[0032] x i x j One position coordinate;

[0033] c 1ε C 2ε A constant.

[0034] Preferably, the erosion simulation analysis results include the area of ​​maximum internal particle velocity, the maximum particle velocity, and the overall velocity of the valve fluid.

[0035] Preferably, the anti-erosion conical throttle valve includes a valve stem, a connecting cylinder, and an anti-erosion funnel connected in sequence. An anti-erosion baffle is sleeved on the valve stem, and a flow hole is formed on the anti-erosion baffle, which connects the anti-erosion baffle and the valve stem. The connecting cylinder is clamped at the outlet end.

[0036] Compared with the prior art, the advantages of the present invention are:

[0037] Simulation analysis was conducted using Workbench software on an existing conical throttle valve and an optimized one, simulating erosion within the conical throttle valve pipeline at 140 MPa, a solid particle diameter of 0.045 mm, a particle flow rate of 0.005 kg / s, and an inlet flow rate of 20 m / s. Simulation results show that, under these conditions, the erosion area inside the pipeline with the optimized conical throttle valve is significantly smaller than that of the existing conical throttle valve in the gas wellhead equipment. Based on the internal velocity field distribution of the optimized conical throttle valve, the internal velocity is significantly higher than that of the existing conical throttle valve. Since the inlet velocity of the optimized conical throttle valve directly affects the internal velocity field distribution, analysis was performed on the optimized conical throttle valve under different inlet velocities to ensure that its erosion prevention effect is superior to that of the existing conical throttle valve, while maintaining a lower internal fluid velocity. Attached Figure Description

[0038] Figure 1 A two-dimensional XY plane diagram of an existing conical throttle valve in a gas wellhead assembly;

[0039] Figure 2 A comparison of simplified 3D XY plane diagrams of a conical throttle valve and a simplified 3D XY plane diagram of an anti-erosion conical throttle valve;

[0040] Figure 3 A simplified structural diagram of the anti-erosion conical throttle valve;

[0041] Figure 4 Simplified two-dimensional parameter diagram of the anti-erosion conical throttle valve in the XY plane;

[0042] Figure 5 The particle distribution diagram of the conical throttle valve when the inlet flow velocity is 20 m / s;

[0043] Figure 6 Particle distribution diagram of anti-erosion conical throttle valve when inlet flow velocity is 20m / s;

[0044] Figure 7 The velocity field distribution of the conical throttle valve when the inlet flow velocity is 20 m / s;

[0045] Figure 8 The velocity field distribution diagram of the anti-erosion conical throttle valve when the inlet flow velocity is 20 m / s;

[0046] Figure 9 The pressure field distribution of the conical throttle valve when the inlet flow velocity is 20 m / s;

[0047] Figure 10 The pressure field distribution of the anti-erosion conical throttle valve when the inlet flow velocity is 20 m / s;

[0048] Figure 11 Particle distribution diagram of the anti-erosion conical throttle valve when the inlet flow velocity is 30 m / s;

[0049] Figure 12 The velocity field distribution diagram of the anti-erosion conical throttle valve when the inlet flow velocity is 30 m / s;

[0050] Figure 13 The pressure field distribution diagram of the anti-erosion conical throttle valve when the inlet flow velocity is 30 m / s;

[0051] Figure 14 Particle distribution diagram of anti-erosion conical throttle valve when inlet flow velocity is 40 m / s;

[0052] Figure 15 The velocity field distribution diagram of the anti-erosion conical throttle valve when the inlet flow velocity is 40 m / s;

[0053] Figure 16 The pressure field distribution diagram of the anti-erosion cone throttle valve when the inlet flow velocity is 40 m / s;

[0054] Figure 17 The particle distribution diagram of the anti-erosion conical throttle valve when the inlet flow velocity is 50 m / s;

[0055] Figure 18The velocity field distribution diagram of the anti-erosion conical throttle valve when the inlet flow velocity is 50 m / s;

[0056] Figure 19 The pressure field distribution of the anti-erosion conical throttle valve is shown when the inlet flow velocity is 50 m / s.

[0057] Figure 20 The particle distribution diagram of the anti-erosion conical throttle valve when the inlet flow velocity is 60 m / s;

[0058] Figure 21 The velocity field distribution diagram of the anti-erosion conical throttle valve when the inlet flow velocity is 60 m / s;

[0059] Figure 22 The pressure field distribution diagram of the anti-erosion conical throttle valve is shown when the inlet flow velocity is 60 m / s.

[0060] Among them, 1-valve stem; 2-anti-erosion baffle; 3-flow hole; 4-anti-erosion funnel; 5-connecting cylinder. Detailed Implementation

[0061] The present invention will now be described in more detail with reference to the accompanying drawings, which illustrate preferred embodiments of the invention. It should be understood that those skilled in the art can modify the invention described herein while still achieving its advantageous effects. Therefore, the following description should be understood as being of general knowledge to those skilled in the art and is not intended to limit the invention.

[0062] This invention provides a novel design optimization method for an anti-erosion conical throttle valve, based on existing conical throttle valves in gas wellhead equipment, such as... Figure 1 To better simulate the existing conical throttle valve, a simplified diagram of an optimized conical throttle valve (anti-erosion conical throttle valve) is shown below. Figure 2 Geometric modeling was performed using 3D software, and simulation analysis was conducted using Workbench software to simulate the erosion inside the conical throttle valve pipeline at 140 MPa, a solid particle diameter of 0.045 mm, a particle flow rate of 0.005 kg / s, and an inlet flow rate of 20 m / s.

[0063] Simulation results analysis shows that, under the above conditions, the erosion zone inside the pipeline is significantly smaller with the anti-erosion conical throttle valve compared to existing conical throttle valves in the gas wellhead equipment. The reasons are as follows:

[0064] like Figure 3As shown, the anti-erosion conical throttle valve is an improvement on the existing conical throttle valve, with the following structure: It includes a valve stem 1, a connecting cylinder, and an anti-erosion funnel 4 connected in sequence. An anti-erosion baffle 2 (cylindrical) is fitted over the valve stem 1. A flow hole is provided on the anti-erosion baffle 2, connecting the anti-erosion baffle 2 and the valve stem 1. The connecting cylinder 5 is secured at the outlet end. The connecting cylinder 5 serves two purposes: firstly, it fixes the anti-erosion baffle 2 and the anti-erosion funnel 4; secondly, it prevents the fluid from directly entering the anti-erosion funnel after passing through the anti-erosion baffle 2, thus avoiding turbulent fluid flow.

[0065] Because the anti-erosion conical throttle valve adds an anti-erosion cylindrical baffle 2 with a flow hole (30mm) on the cylindrical wall, the contact area between the particles and the valve core (valve stem 1) of the throttle valve is reduced, thereby reducing erosion at the valve core. The anti-erosion funnel 4 also has a 0.005mm opening on its wall. On the one hand, this facilitates the passage of solid particles with a diameter of 0.045mm while also making the area of ​​the flow hole smaller. On the other hand, it changes the internal particle flow, dispersing the internal particles through various small holes to avoid large-area erosion areas like those found in existing conical throttle valves.

[0066] However, based on the internal velocity field distribution (particle velocity and overall velocity, two types of velocities) of the anti-erosion conical throttle valve, the internal velocity of the anti-erosion conical throttle valve is significantly higher than that of the existing conical throttle valve (due to the addition of the anti-erosion cylindrical baffle 2 and the anti-erosion funnel 4, the internal flow port of the anti-erosion conical throttle valve becomes smaller, thereby increasing the internal particle velocity, which is significantly higher than that of the existing conical throttle valve, approximately twice the velocity of the existing conical throttle valve). The inlet velocity of the anti-erosion conical throttle valve directly affects the internal velocity field distribution, so the following analysis will be conducted on the anti-erosion throttle valve under different inlet velocities.

[0067] Finally, an inlet flow rate between 30 m / s and 40 m / s was selected, which was the most suitable for both the anti-erosion effect and the internal fluid flow rate of the anti-erosion cone throttle valve.

[0068] The design optimization method of this novel anti-erosion conical throttle valve:

[0069] S1: Design the structural parameters of the anti-erosion conical throttle valve based on the basic parameters of the conical throttle valve in the gas wellhead device of the valve design manual.

[0070] like Figure 4 The structural parameters of the anti-erosion conical throttle valve are as follows: valve wall thickness is 5mm, inlet channel width is 78mm, inlet channel length is 150mm, outlet channel width is 50mm, outlet channel length is 200mm, anti-erosion baffle orifice (diameter of flow hole on anti-erosion baffle) is 24mm, anti-erosion funnel length is 50m, and funnel wall orifice (diameter of flow hole on funnel wall) is 0.5mm.

[0071] S2: Based on the structural parameters obtained in step S1, use Solidworks 3D modeling software to draw a simplified 3D model of the anti-erosion conical throttle valve and the simplified 3D model of the conical throttle valve in step S1.

[0072] The simplified three-dimensional model of the anti-erosion conical throttle valve retains only the inlet channel, anti-erosion baffle, conical valve stem, and outlet channel.

[0073] Finally, material properties were set and meshed for the simplified model in ANSYS Workbench. Material properties were assigned to the simplified model. Specifically, the flow field was set as an incompressible viscous fluid using the standard k-ε model; the internal pressure was set to 140 MPa, the solid particle diameter to 0.045 mm, the particle flow rate to 0.005 kg / s, and the inlet flow rate to 20 m / s.

[0074] To simplify the simulation and improve its accuracy, the internal fluid was configured as follows: (1) There was no fluid flow in the vertical direction of the conical throttle valve; (2) The fluid was set to be an incompressible viscous fluid; (3) Gravity had no effect on the internal fluid and particles; (4) No heat transfer occurred inside the conical throttle valve; (5) The device was in a steady state, and the outlet fluid was in a free state. All other settings were set to system default.

[0075] S3: Import the two simplified models from step S2 into WorkbenchFluent software, and perform erosion simulation analysis on the two simplified models at an inlet flow velocity of 20m / s based on the erosion model.

[0076] The erosion simulation analysis results include the area of ​​maximum internal particle velocity, the maximum particle velocity, and the overall flow velocity of the valve fluid.

[0077] Regarding the internal particle situation of existing conical throttle valves and anti-erosion conical throttle valves in gas wellhead equipment, such as... Figure 5 , Figure 6 The velocity field distribution is as follows Figure 7 , Figure 8 Pressure field distribution as follows Figure 9 , Figure 10 .

[0078] The maximum particle velocity of the existing conical throttle valve in the gas wellhead equipment is located at the top of the conical valve core and the left end of the entire outlet channel. Therefore, the erosion in this area is the most severe, with a maximum particle velocity of 19.2 m / s and a maximum overall fluid velocity of 18.3 m / s.

[0079] The maximum particle velocity of the newly designed anti-erosion conical throttle valve is located at the left and right ends of the conical valve core inlet, the lower outlet of the anti-erosion funnel, and the bottom outlet of the anti-erosion funnel wall. Therefore, the erosion in this area is the most severe, and the maximum velocity area is much smaller than that of the existing conical throttle valve in the gas wellhead device.

[0080] However, the maximum particle velocity of the anti-erosion cone throttle valve is 27 m / s, and the maximum overall flow velocity of the valve fluid is 26.2 m / s. The flow velocity in the channel (maximum particle velocity and overall flow velocity of the valve fluid) is much faster than that of the existing cone throttle valve.

[0081] Although the maximum velocity area of ​​the anti-erosion conical throttle valve is much smaller than that of the existing conical throttle valve, and the anti-erosion effect is obvious, the improvement in the anti-erosion effect also brings about a significant increase in the internal fluid velocity. Therefore, the anti-erosion conical throttle valve still needs further optimization in terms of internal velocity. Since the inlet velocity directly affects the internal velocity field distribution, the following analysis will be conducted on the anti-erosion throttle valve under different inlet velocities.

[0082] S4: Import the simplified model of the anti-erosion conical throttle valve from step S2 into WorkbenchFluent software, and perform erosion simulation analysis on the anti-erosion conical throttle valve at different flow velocities than 20 m / s based on the erosion model.

[0083] The erosion simulation analysis results include the area of ​​maximum internal particle velocity, the maximum particle velocity, and the overall flow velocity of the valve fluid.

[0084] (1) Erosion simulation analysis was performed on an anti-erosion conical throttle valve with an inlet flow velocity of 30 m / s. The internal particle situation is as follows: Figure 11 The velocity field distribution is as follows Figure 12 Pressure field distribution as follows Figure 13 .

[0085] Compared to the erosion situation of the anti-erosion conical throttle valve with an inlet flow rate of 20 m / s, when the inlet flow rate is 30 m / s, the maximum particle velocity of the anti-erosion conical throttle valve is located at the right end of the conical valve core inlet, the lower outlet of the anti-erosion funnel, and the bottom outlet of the anti-erosion funnel wall. Therefore, the erosion is most severe in this area, and the area (see the overall flow velocity diagram of the valve, look at the darkest areas, the darkest areas represent the most severely eroded parts) is slightly smaller than that of the anti-erosion conical throttle valve with an inlet flow rate of 20 m / s. Its maximum particle velocity is 16.5 m / s, and the maximum overall flow velocity of the valve fluid is 16.2 m / s. Compared with similar velocities, both are much smaller than those of the anti-erosion conical throttle valve with an inlet flow rate of 20 m / s, with a difference of about 10 m / s, and about 2.5 m / s smaller than existing conical throttle valves.

[0086] (2) Erosion simulation analysis was performed on an anti-erosion conical throttle valve with an inlet flow velocity of 40 m / s. The internal particle situation is as follows: Figure 14 The velocity field distribution is as follows Figure 15 Pressure field distribution as follows Figure 16 .

[0087] Compared to the erosion situation of the anti-erosion conical throttle valve with an inlet flow rate of 20 m / s, when the inlet flow rate is 40 m / s, the maximum particle velocity of the anti-erosion conical throttle valve is located at the right end of the conical valve core inlet, the lower outlet of the anti-erosion funnel, and the bottom outlet of the anti-erosion funnel wall. Therefore, the erosion is most severe in this area, which is slightly smaller than that of the anti-erosion conical throttle valve with an inlet flow rate of 20 m / s, and consistent with that with an inlet flow rate of 30 m / s; however, its maximum particle velocity is 22 m / s, and the maximum overall flow velocity of the valve fluid is 21.5 m / s, which is similar to that with an inlet flow rate of 20 m / s. Compared to the anti-erosion conical throttle valve, the difference in velocity between the two is about 5 m / s (the difference between the maximum particle velocity at an inlet flow rate of 40 m / s and 30 m / s is 5 m / s; the difference between the overall valve fluid velocity at an inlet flow rate of 40 m / s and 30 m / s is 5 m / s; the difference between the two velocities is 5 m / s compared to the previous ones). However, it shows a significant increase compared to an inlet flow rate of 30 m / s, and is about 4 m / s larger than existing conical throttle valves.

[0088] (3) Erosion simulation analysis was performed on anti-erosion conical throttle valves with inlet flow velocities of 50 m / s and 60 m / s, and the internal particle situation was as follows: Figure 17 , 20 The velocity field distribution is as follows Figure 18 , 21 Pressure field distribution as follows Figure 19 , 22 The maximum particle velocity of the anti-erosion conical throttle valve is basically the same as the inlet velocity of 40 m / s. However, the maximum particle velocities are 27.5 m / s and 33 m / s respectively, and the maximum overall flow velocity of the valve fluid is 26.5 m / s and 31.8 m / s respectively, which shows a linear upward trend.

[0089] Among them, the erosion model formulas in steps S3 and S4 are:

[0090]

[0091] In the formula, R erosion - Wear rate per unit area of ​​the wall surface, kg / m 2 -s;

[0092] Nparticle - the number of colliding particles per unit area;

[0093] M P - Mass flow rate of colliding particles, kg / s;

[0094] c(dP - The shape function of particle size;

[0095] A face - Area of ​​the wall calculation unit, m 2 ;

[0096] f(θ1) - Impact angle function;

[0097] This is a particle relative function.

[0098] The simulation analysis in steps S3 and S4 is based on the turbulent kinetic energy k and the dissipation rate ε, with the specific expressions as follows:

[0099]

[0100]

[0101]

[0102]

[0103]

[0104] G k One is the generation of turbulent kinetic energy due to the average velocity gradient;

[0105] G b One type of turbulent kinetic energy is generated due to the influence of buoyancy. For incompressible fluids, G b =0;

[0106] Y M The effect of compressible turbulent pulsating expansion on the total dissipation rate, for incompressible fluids, is given by Y. M =0;

[0107] μ t μ i μ j A turbulent viscosity coefficient;

[0108] ρ is the fluid density;

[0109] ε is the dissipation rate of turbulent pulsating kinetic energy;

[0110] x i x j One position coordinate;

[0111] c 1ε C 2ε A constant.

[0112] S5: Compare the erosion simulation analysis results in steps S3 and S4, and select the inlet flow velocity of the anti-erosion conical throttle valve.

[0113] Considering the maximum particle velocity area, maximum particle velocity, and overall fluid velocity within the throttle valve, when the internal pressure is set to 140 MPa, the solid particle diameter is 0.045 mm, and the particle flow rate is 0.005 kg / s, the inlet velocity should be controlled between 30 m / s and 40 m / s for optimal erosion resistance and internal fluid velocity.

[0114] The above are merely preferred embodiments of the present invention and do not constitute any limitation on the present invention. Any equivalent substitutions or modifications made by those skilled in the art to the technical solutions and content disclosed in the present invention without departing from the scope of the present invention shall be deemed to have remained within the protection scope of the present invention.

Claims

1. A design optimization method for a novel anti-erosion conical throttle valve, characterized in that, Includes the following steps: S1: Design the structural parameters of the anti-erosion cone throttle valve based on the basic parameters of the cone throttle valve in the gas wellhead device of the valve design manual; S2: Create simplified models of the 3D model of the conical throttle valve and the 3D model of the erosion-resistant conical throttle valve, and set material properties and mesh the simplified models in ANSYS Workbench: The anti-erosion conical throttle valve includes a valve stem, a connecting cylinder, and an anti-erosion funnel connected in sequence. An anti-erosion baffle is sleeved on the valve stem. A flow hole is opened on the anti-erosion baffle, and the flow hole connects the anti-erosion baffle and the valve stem. The connecting cylinder is clamped at the outlet end. S3: Import the two simplified models from step S2 into WorkbenchFluent software, and perform erosion simulation analysis on the two simplified models at an inlet flow velocity of 20m / s based on the erosion model. The simulation analysis is based on the turbulent kinetic energy k and the dissipation rate ε, with the specific expression as follows: ； ； ； ； ； G k One is the generation of turbulent kinetic energy due to the average velocity gradient; G b One type of turbulent kinetic energy is generated due to the influence of buoyancy. For incompressible fluids, G b =0; Y M The effect of compressible turbulent pulsating expansion on the total dissipation rate, for incompressible fluids, is given by Y. M =0; μ t μ i μ j A turbulent viscosity coefficient; ρ is the fluid density; ε is the dissipation rate of turbulent pulsating kinetic energy; x i x j One position coordinate; c 1ε C 2ε One constant; S4: Import the simplified model of the anti-erosion conical throttle valve from step S2 into WorkbenchFluent software, and perform erosion simulation analysis on the anti-erosion conical throttle valve at different flow velocities than 20m / s based on the erosion model. S5: Compare the erosion simulation analysis results in steps S3 and S4, and select the inlet flow velocity of the anti-erosion cone throttle valve; The erosion simulation analysis results include the area of ​​maximum internal particle velocity, maximum particle velocity, and overall valve fluid velocity. The internal pressure is set to 140 MPa, the solid particle diameter is 0.045 mm, the particle flow rate is 0.005 kg / s, and the inlet velocity is controlled between 30 m / s and 40 m / s.

2. The design optimization method for the novel anti-erosion conical throttle valve according to claim 1, characterized in that, The erosion model formula in step S3: ； In the formula, R erosion - Wear rate per unit area of ​​the wall surface, kg / m 2 -s; Nparticle - the number of particles colliding per unit area; M P - Mass flow rate of colliding particles, kg / s; c(d p - The shape function of particle size; A face - Area of ​​the wall calculation unit, m 2 ; f(θ1) - Impact angle function; This is a particle relative function.

Images