Forming method of composite material special-shaped yacht cab

Abstract

The invention discloses a forming method of a composite material special-shaped yacht cab in the technical field of composite material manufacturing, which comprises the following steps of: performing resin flow simulation based on a three-dimensional model, and identifying a high-resistance area; a flow guide system and a layering scheme are optimally designed; arranging a diversion net by adopting a layered laying strategy; the flow effect is optimized through experimental verification; a vacuum system is constructed, and multi-inlet synchronous glue injection is carried out; and gradient curing molding and post-treatment are carried out, so that the production of products is realized. According to the method, through CFD flow simulation and dynamic diversion system optimization, flow lag of high-resistance areas such as curved surfaces and sharp corners is accurately predicted and compensated, the infiltration effect of resin in a complex structure is remarkably improved by combining layered diversion net design and a stress-oriented layering strategy, common defects such as dry spots and pores in a traditional process are fundamentally eliminated, and the method is suitable for large-scale production. And the forming quality of complex components such as the special-shaped yacht cab is greatly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite material manufacturing, in particular to a forming method of a composite material special-shaped speedboat cabin. BACKGROUND

[0002] Vacuum infusion process is an advanced composite material manufacturing technology, which mainly involves inorganic non-metallic materials. The process involves laying reinforcing materials (such as glass fibers, carbon fibers, etc.) on a mold, covering a vacuum bag, and then pumping out the air in the system to form a negative pressure environment in the mold cavity. In this environment, the resin material is pressed into the fiber layer through the pre-laid pipeline, completing the flow process and finally solidifying into a product.

[0003] With the development of modern industry, the demand for composite materials is increasing, especially in the aerospace, automotive manufacturing, wind power and other industries. These industries often need to use composite material parts with complex shape and high performance requirements. Although the traditional vacuum infusion process is very mature, there are still many limitations in dealing with large or complex-shaped products, such as difficulty in removing air bubbles, uneven resin distribution, etc. Therefore, it is particularly important to develop a new method that can effectively solve the above problems.

[0004] However, the existing technology has some problems: in the composite vacuum infusion process, the fiber layup maintains uniform distribution in the flat area, forming a coherent pore network that allows resin to flow smoothly. However, when encountering complex geometries such as curved surfaces or sharp corners, the fiber bundles will deform significantly due to bending stress and compression: on the one hand, local accumulation of fibers leads to a sharp reduction in pore size, greatly increasing the flow resistance; on the other hand, at the corner with a small radius of curvature, the fiber may even appear to be bridged, forming a completely suspended micro dead zone, causing the path selection effect of resin flow, that is, the fluid instinctively follows the principle of least resistance, preferring to pass through the flat area with high permeability, while bypassing the complex structure area with a sudden drop in permeability;

[0005] More seriously, this flow inhomogeneity will form a positive feedback loop: the rapid filling of the main flow channel will deplete the driving force prematurely, and the resin in the stagnant area may cause viscosity to rise or pre-solidification due to prolonged residence time, ultimately forming dry spot defects that are difficult to eliminate in the product, and resin un-wetting phenomenon is easy to appear in the complex curved surface and corner, thereby affecting the quality of the final product. Therefore, we propose a forming method of a composite material special-shaped speedboat cabin. SUMMARY

[0006] In view of the deficiencies in the prior art, the present application provides a forming method of a composite material special-shaped speedboat cabin

[0007] The object of the present application is achieved by a method for forming a composite profiled cabin of a high-speed yacht, comprising the following steps:

[0008] S1, constructing a three-dimensional model based on the structure of the cabin, and performing resin flow simulation to obtain a flow guide analysis result;

[0009] S2, calculating flow guide pipe parameters according to the simulated flow guide analysis result to generate a flow guide system;

[0010] S3, generating a layering table according to the flow guide analysis result of step S1 in combination with the laying position of the flow guide net;

[0011] S4, laying the fiber reinforced layer on the mold according to the layering table, and arranging the flow guide system at the predetermined position based on the layering laying strategy;

[0012] S5, setting up a resin flow experiment plate to verify the resin flow rate;

[0013] S6, laying auxiliary materials on the fiber reinforced layer and extending the coverage, and setting up a vacuum bag to construct a vacuum system;

[0014] S7, synchronously injecting resin through multiple inlets and dynamically adjusting the injection pressure;

[0015] S8, curing the resin by using a gradient curing process and demolding to prepare the product.

[0016] Optionally, in step S1, the resin flow simulation specifically comprises:

[0017] The data parameters of the three-dimensional model and the porosity of the fiber preform are input into the software model as data;

[0018] Material parameters are set based on material properties;

[0019] Boundary conditions are defined, including resin inlet pressure, flow rate, outlet pressure and contact angle;

[0020] The flow guide analysis result is obtained through model simulation calculation.

[0021] Optionally, the flow guide analysis result comprises:

[0022] Filling time cloud map: identifying the last filled area for marking the potential dry spot position;

[0023] Pressure distribution map: positioning the high pressure difference area for marking the area that needs to be optimized for flow guide;

[0024] Flow velocity vector diagram: for checking the resin flow around the flow guide.

[0025] Optionally, the flow guide pipe parameters include flow guide pipe length and flow guide net laying area;

[0026] The formula for calculating the length of the flow guide pipe is specifically:

[0027]

[0028] L is the length of the flow guide pipe;

[0029] K is the permeability of the fiber prepreg;

[0030] ΔP is the pressure difference;

[0031] t is the target filling time;

[0032] μ is the dynamic viscosity of the resin;

[0033] is the fiber porosity;

[0034] C is the curvature correction coefficient.

[0035] 5. The forming method of the composite profiled yacht cabin according to claim 4, characterized in that the area with a flow velocity lower than 50% of the average flow velocity is extracted from the simulation results as the flow guide net laying area.

[0036] The projected area Azone of the area is calculated through geometric modeling;

[0037] The flow guide net laying area The calculation formula is specifically:

[0038]

[0039] Wherein: is the flow compensation coefficient;

[0040] is the flow guide net overlap coefficient.

[0041] Optionally, the flow of step S3 is specifically:

[0042] S31, convert the principal stress direction calculated by the software model into fiber orientation to obtain the ply analysis result;

[0043] S32, divide the profit area according to the stress nephogram, wherein the high stress area is thickened;

[0044] S33, set the ply sequence according to the laminate balance condition, and verify the rationality of the ply sequence by using the stiffness matrix;

[0045] S34, combine the flow guide system to optimize the ply sequence and generate the ply table.

[0046] Optionally, the step S34 is specifically:

[0047] Unidirectional tape (UD) regions are arranged with narrow flow channels along the fiber direction;

[0048] Fabric regions are arranged with low-resistance flow guide nets;

[0049] Round or curved region layers are arranged in a decreasing manner to form natural flow channels;

[0050] Thick regions or core material junctions are increased with air-permeable felt or high-permeability medium;

[0051] The resin flow simulation is used to set the glue inlet and exhaust port positions.

[0052] Optionally, in step S4, the layer-by-layer laying strategy is specifically:

[0053] For fiber layers with a thickness > 5mm, a clamping structure is used to set the flow guide net:

[0054] The lower flow guide net covers 50% of the bottom area of the high-resistance region;

[0055] The middle layer is a thick fiber layer;

[0056] The upper flow guide net covers 50% of the top area and is connected to the branch flow guide pipe.

[0057] Optionally, the specific process of step S5 is:

[0058] Based on the layer table and the flow guide system, a model plate with the same structure is set, which is consistent with the product;

[0059] Among them, half of the structure of the plate is set with flow guide nets, and the other half is not set with flow guide nets;

[0060] Perform the infusion operation and record the infusion completion time on both sides of the plate;

[0061] Check the infusion effect and adjust and optimize the flow guide system accordingly.

[0062] Optionally, the process of step SS6 is specifically:

[0063] S61, two vacuum bags are bonded with sealing tape and sealed;

[0064] S62, connect the vacuum bag with the vacuum pipeline, and vacuum the vacuum bag to be slightly tight to perform the bridging process;

[0065] S63, perform pressure maintenance test on the vacuum bag to check the sealing qualification of the vacuum bag;

[0066] S64, perform the intubation process and connect the buffer tank, and then connect the buffer tank to the vacuum pump;

[0067] S65, perform secondary packaging on the vacuum bag, and compact the vacuum bag with the sealing tape;

[0068] S66, vacuum test is performed.

[0069] Compared with the prior art, the application can significantly improve the resin infiltration effect in complex structures by CFD flow simulation and dynamic flow guiding system optimization, accurate prediction and compensation of flow hysteresis in high resistance areas such as curved surfaces and sharp corners, combined with layered flow guiding net design and stress oriented layering strategy, fundamentally eliminating common defects such as dry spots and pores in traditional processes, and greatly improving the molding quality of complex components such as complex fast boat cabins;

[0070] In addition, the application realizes the intelligentization and standardization of composite material molding process through the closed-loop manufacturing process integrating numerical simulation, experimental verification and process control, not only reduces the dependence on the experience of operating personnel in production, but also reduces the trial and error cost and raw material waste through optimizing the flow guiding net arrangement and material consumption, improves the production efficiency and economic benefit while ensuring the product quality, and provides reliable technical support for the large-scale production of composite material products. BRIEF DESCRIPTION OF DRAWINGS

[0071] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0072] Figure 1 is the isometric view of the cabin skin structure provided by the present application.

[0073] Figure 2 is the bottom view of the cabin skin structure provided by the present application.

[0074] Figure 3 is the auxiliary material laying schematic diagram provided by the present application.

[0075] Figure 4 is the overall step flow framework schematic diagram provided by the present application.

[0076] Figure 5 is the process flow schematic diagram provided by the present application. DETAILED DESCRIPTION

[0077] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0078] As Figures 1 to 4 shown in a composite profile yacht cabin forming method, comprising the following steps:

[0079] S1, based on the structure of the cabin to build a three-dimensional model, and resin flow simulation, get the flow analysis results;

[0080] The resin flow simulation is specifically:

[0081] The data parameters of the three-dimensional model and the porosity of the fiber preform are input into the software model as data;

[0082] Based on the material properties, set the material parameters;

[0083] Define the boundary conditions, including resin inlet pressure, flow rate, outlet pressure and contact angle;

[0084] Get the flow analysis results by model simulation calculation.

[0085] It should be noted that the data parameters of the three-dimensional model mainly include the geometric parameters, material parameters and process boundary requirements of the product model, and the porosity of the fiber preform is directly called from the database, which is a conventional existing data;

[0086] In addition, the three-dimensional model is constructed based on the CAD model of the cabin structure, and the local grid is encrypted in key parts such as curved surface, reinforcing rib and thickness mutation area;

[0087] The material properties are mainly the viscosity of the resin, which is measured by a rheometer.

[0088] Specifically, the flow analysis results include:

[0089] Filling time cloud map: identify the last filled area, which is used to mark the potential dry spot position;

[0090] Pressure distribution map: locate the high pressure difference area, which is used to mark the area that needs to be optimized for flow;

[0091] Flow velocity vector diagram: used to check the resin flow situation;

[0092] Further, the CFD software model simulates the resin flow front advancing process, and identifies the last filled area through the filling time cloud map, wherein the cloud map contains color gradient, different colors represent the time when the resin reaches the position, and the resin flow path and fast and slow areas can be directly displayed;

[0093] Connect the areas with the same filling time through the isochronal line, which is used to judge whether the flow front advancing is smooth or not, and whether there is abnormal retention;

[0094] Wherein, the area with the latest discoloration in the cloud chart is the last filling point, indicating that the dry spot risk is the highest here, which needs to be optimized first, and the area with a resin filling time difference exceeding 10% of the total filling time is the area that needs to be optimized by flow guiding;

[0095] Further, the area with a curvature radius less than 50 mm is marked as a high flow resistance area based on the pressure distribution map.

[0096] S2, calculating flow guide pipe parameters according to the simulated flow guide analysis results to generate a flow guide system;

[0097] The flow guide pipe parameters include flow guide pipe length and flow guide net laying area;

[0098] In step S2, the formula for calculating the flow guide pipe length is specifically:

[0099] The flow guide pipe length L needs to ensure that the resin reaches the direct current area within a predetermined time t,

[0100]

[0101] Wherein: L is the length of the flow guide pipe;

[0102] K is the permeability of the fiber prepreg;

[0103] ΔP is the pressure difference;

[0104] t is the target filling time;

[0105] μ is the dynamic viscosity of the resin;

[0106] is the fiber porosity;

[0107] C is the curvature correction coefficient.

[0108] It should be noted that the determination of the curvature correction coefficient C is specifically: for every 10 mm decrease in the curvature radius, C increases by 0.05-0.1;

[0109] Fiber orientation effect: due to the large transverse flow resistance, the C value of the orthogonal layer is 20-30% higher than that of the unidirectional layer;

[0110] Based on the ASTM D5681 standard, the permeability K preferably uses the actual measured data of the actual prepreg under process pressure;

[0111] The calculation of the flow guide pipe length is based on resin flow dynamics, and through parameters such as permeability, pressure difference, viscosity, and porosity, the resin reaches the stagnation area within the target time, wherein the curvature correction coefficient (C) is adjusted according to the degree of curvature of the area and the fiber layer direction - the smaller the curvature radius or the presence of transverse flow, the C value significantly increases to compensate for the flow resistance;

[0112] Further, when simulating, if multiple stagnation zones need to be calculated, take the calculation length Lmax of the farthest stagnation zone as the design value of the flow guide pipe;

[0113] For curved surface areas, the length of the flow guide pipe needs to increase by the curvature compensation amount, and the length increases by 5% for every 10mm decrease in the radius of curvature;

[0114] The final design of the flow guide system needs to be determined in combination with the measured permeability data and the simulation results to ensure that all high-risk areas are covered.

[0115] The calculation of the laying area of the flow guide net is specifically;

[0116] From the simulation results, the area where the flow rate is less than 50% of the average flow rate is extracted as the flow guide net laying area.

[0117] The projected area Azone of the area is calculated by geometric modeling

[0118] The area amplification coefficient is determined, and the specific formula is:

[0119]

[0120] is the flow compensation coefficient;

[0121] is the flow guide net overlap coefficient.

[0122] Further, The value of is usually (0.2~0.5), which is positively correlated with the complexity of the curved surface, The value of is usually (1.1~1.2), and when multiple layers are laid, the overlapping area needs to be considered;

[0123] The laying area of the flow guide net needs to consider factors such as low-speed flow area, flow compensation, and laying overlap,

[0124] From the simulation results, the area where the flow rate is less than 50% of the average flow rate is extracted as the flow guide net laying area. These areas have difficulty flowing resin and need to be enhanced by the flow guide net to increase permeability,

[0125] Flow compensation coefficient : Compensate for the flow resistance caused by curved surfaces or complex structures, with a value range of 0.2~0.5. The more complex the curved surface, The greater.

[0126] Overlap coefficient : Consider the overlapping area when laying multiple layers of flow guide nets, with a value range of 1.1~1.2 (the more layers, the larger the β).

[0127] When the overlap is insufficient, it will cause the resin to flow discontinuously, forming dry spots;

[0128] When the overlap is too much, it will cause material waste and reduce the local fiber volume fraction.

[0129] Further, by precisely covering the low-speed flow area, the flow guide net can effectively enhance the resin permeability, avoid dry spot defects, ensure the uniformity of the mechanical properties of the component, optimize the flow compensation coefficient, solve the flow lag problem of curved surfaces or complex structures, and reduce the uneven filling caused by geometric mutations;

[0130] In addition, the overlap coefficient can take into account the continuity of the flow guide and the economy of materials. Moderate overlap can eliminate interlayer gaps and ensure unobstructed diffusion of resin, while avoiding excessive overlap that causes local fiber loosening and cost waste. Ultimately, this strategy can improve process stability while reducing trial and error costs and waste rates.

[0131] S3, generating a layup table according to the flow guide analysis result of step S1 and the flow guide net laying position;

[0132] The flow of step S3 is specifically:

[0133] S31, converting the principal stress direction calculated by the software model into fiber orientation to obtain a layup analysis result;

[0134] S32, dividing the profit area according to the stress cloud map, wherein the high stress area is thickened;

[0135] S33, setting the layup sequence according to the balance condition of the laminate, and verifying the rationality of the layup sequence by using the stiffness matrix;

[0136] S34, optimizing the layup sequence in combination with the flow guide system to generate a layup table.

[0137] The step S34 is specifically:

[0138] The unidirectional tape (UD) area is arranged with narrow flow guide grooves along the fiber direction;

[0139] The fabric area is arranged with low-resistance flow guide nets;

[0140] The layup of the rounded or curved area is arranged in a decreasing manner to construct a natural flow channel;

[0141] The thick area or the core material junction is increased with air-permeable felt or high-permeability medium;

[0142] The resin injection port and exhaust port positions are set based on resin flow simulation.

[0143] It should be noted that the generation of the layup table and the flow guide system will directly affect the mechanical properties, forming quality and process efficiency of the component. Therefore, by combining the flow guide analysis result and the layup optimization strategy, the reliability of the product can be significantly improved, the defect rate can be reduced, and the production process can be optimized;

[0144] Further, in the layup design stage, first, the principal stress direction calculated by finite element analysis is converted to fiber orientation to ensure that the layup direction is highly consistent with the load path, second, a data-driven layup strategy is adopted to maximize the load-bearing efficiency of the fibers, avoiding local strength deficiency or stiffness reduction caused by deviation of the fiber direction from the principal stress direction, and at the same time, the rationality of the layup sequence is verified by the stiffness matrix to ensure that the mechanical properties of the laminate meet the design requirements, reducing the risk of structural failure caused by layup instability or coupling effect;

[0145] Further, based on the stress cloud map, the high stress area is divided and the layup is thickened, which can improve the carrying capacity of the key area, avoid material waste and weight increase caused by overall thickening, and at the same time, reduce the risk of early damage caused by stress concentration;

[0146] For example, in an aviation structure or a wind turbine blade, targeted reinforcement of high stress areas such as connection parts or bending areas can significantly prolong the fatigue life and improve the structural reliability.

[0147] Further, based on the balance condition of the laminate, the layup sequence is set to reduce the thermal residual stress and deformation during curing, thereby realizing the suppression of warping problems caused by asymmetric or unbalanced layup and ensuring the dimensional stability of the formed component.

[0148] Further, narrow flow guide grooves are arranged in the unidirectional tape (UD) area: flow channels are arranged along the fiber direction to promote resin flow using the natural gaps of fiber arrangement, avoiding flow blockage caused by tight fiber arrangement;

[0149] Low-resistance flow guide net is used in the fabric area: the anisotropic flow characteristics of the fabric itself make the transverse permeation of the resin slow, and covering a low-resistance flow guide net can balance the flow speed and ensure uniform infiltration;

[0150] Decreasing layup is used in the corner or curved surface area: by gradually changing the thickness of the layup, a natural flow channel is formed to reduce the phenomenon of resin stagnation or unstable flow front caused by geometric discontinuity;

[0151] High-permeability medium is added at the junction of thick areas or core materials: thick layer areas or sandwich structures are prone to filling difficulties due to long resin flow paths, and the addition of air-permeable felt or high-permeability medium can shorten the flow distance and improve the filling efficiency;

[0152] Based on resin flow simulation, the positions of the glue injection port and the exhaust port are optimized to accurately control the flow front of the resin, avoid dry areas or bubble stagnation caused by unbalanced flow, and flexibly adjust according to the geometric complexity of the component to ensure that the resin completely fills the mold cavity within a predetermined time. At the same time, the optimized arrangement of the exhaust port can effectively exhaust the air and volatile components in the preform, reduce the porosity, and improve the structural density of the composite material.

[0153] S4, lay up fiber reinforced layers on the mold according to the layup table, and arrange the flow guide system at the predetermined position based on the layered layup strategy;

[0154] The layered layup strategy comprises:

[0155] For a fiber layer with a thickness greater than 5 mm, the flow guide net is arranged in a sandwich structure:

[0156] The lower flow guide net covers 50% of the area at the bottom of the high resistance area;

[0157] The middle layer is a thick fiber layer;

[0158] The upper flow guide net covers 50% of the area at the top and is connected to the branch flow guide pipe.

[0159] Further, by using the layered layup strategy and combining with the sandwich flow guide net design, the resin infiltration effect of thick layer composite material can be optimized, and the forming quality and process reliability can be improved. For a relatively thick fiber reinforced layer, the traditional single layer flow guide is prone to uneven filling due to the long flow path, while the sandwich structure effectively shortens the resin flow distance by covering the high resistance area with layered flow guide nets, avoiding dry spots or trapped bubbles.

[0160] Among them, the lower flow guide net preferentially guides the resin to penetrate into the bottom high resistance area to ensure sufficient infiltration; the middle thick fiber layer provides the main load bearing structure; and the upper flow guide net cooperates with the branch flow guide pipe to accelerate the top filling and form a balanced flow front.

[0161] S5, set up a resin flow experiment plate to verify the resin flow rate;

[0162] Based on the same model plate as the layup table and flow guide system setting structure, the structure is consistent with the product;

[0163] Among them, half of the structure of the plate is provided with a flow guide net, and the other half is not provided with a flow guide net;

[0164] Perform the infusion operation and record the infusion completion time on both sides of the plate;

[0165] Verify the infusion effect and adjust and optimize the flow guide system accordingly;

[0166] It should be noted that in the resin flow verification experiment, the same resin system (such as epoxy resin, unsaturated polyester or vinyl ester) as the actual product is used for infusion to ensure the comparability of the flow characteristics. The infusion pressure is set according to the resin viscosity and fiber permeability, and a controllable negative pressure is applied in combination with the vacuum assisted process to simulate the real forming conditions;

[0167] By comparing the filling time difference between the flow guide area and the non-flow guide area, the improvement effect of the flow guide net on the flow efficiency can be quantitatively evaluated. If it is found that the flow front is uneven or there is a lag area, the density, layout of the flow guide net or the introduction of auxiliary flow channels can be adjusted accordingly until the filling time on both sides tends to be balanced, ensuring that the optimized flow guide system can effectively improve the product forming quality.

[0168] S6, laying auxiliary material on the fiber reinforced layer, extending coverage, and setting a vacuum bag to build a vacuum system;

[0169] It should be noted that the auxiliary material is a nylon peelable cloth, which is fully laid on the fiber reinforced material and needs to extend outward at least 20 cm;

[0170] Further, the key to bottom glue injection is that the resin needs to reach the 6 edges of the bottom surface at the same time, and needs to slow down in the length direction and accelerate in the width direction;

[0171] Because the glass fiber reinforced material itself has a certain rigidity, it is difficult to completely fit at the angle with the mold, so there is a certain gap at the angle between the layer and the mold. These gaps will become "flow guide pipes" during glue injection, accelerating the flow of resin, making the angle fill with glue in advance, and most of the fibers on the vertical surface have not been infiltrated, causing the injection speed to be out of control.

[0172] The flow of step S6 is specifically:

[0173] S61, two vacuum bags are bonded with sealing tape and sealed;

[0174] S62, connect the vacuum bag with the vacuum pipeline, and draw the vacuum bag to be slightly tight to perform bridge processing;

[0175] S63, perform pressure retention test on the vacuum bag to check the sealing qualification of the vacuum bag;

[0176] Further, the pressure retention test is specifically: after the vacuum bag is vacuumed to-92KPa, the vacuum source is closed, and the pressure is retained for 10 minutes. If the vacuum degree decreases by no more than 10KPa after 10 minutes, the vacuum bag sealing is qualified;

[0177] If the vacuum degree decreases by more than 10KPa, the vacuum bag needs to be repaired until it meets the requirements. If multiple repairs still do not meet the vacuum pressure requirements, a new vacuum bag needs to be resealed and tested repeatedly until it is qualified.

[0178] S64, perform cannula processing and connect the buffer tank, and then connect the buffer tank to the vacuum pump;

[0179] S65, perform secondary sealing of the vacuum bag, and compact the vacuum bag and the sealing tape;

[0180] S66, perform vacuum test.

[0181] Further, by adopting the double vacuum bag bonding design, combined with the sealing rubber strip compaction, air leakage can be effectively prevented, ensuring the reliability of the vacuum environment, and the bridging treatment is used to make the vacuum bag uniformly adhere to the fiber layer, avoiding uneven resin flow caused by wrinkles or local looseness;

[0182] S7, resin is injected synchronously through multiple inlets, and the injection pressure is dynamically adjusted;

[0183] S8, using gradient curing process to cure and demold the resin to prepare the product.

[0184] For example, in the bottom area, the PE flow guide net is disconnected, and a buffer zone is set to prevent the resin from reaching the included angle of each vertical surface too quickly.

[0185] The glue injection sequence is from the middle of the bottom to the two sides of the relay type glue injection, and the resin flows from the middle of the bottom to the two sides of the glue injection pipe, and at the same time reaches the edge line of the bottom, and then simultaneously spreads from the bottom of the surrounding vertical surface upwards;

[0186] Therefore, the length of the middle flow guide pipe of the bottom is estimated S1=215-(5×5+1.2×10+1.2×15)×2=105cm

[0187] The length of the two glue injection pipes on both sides of the middle glue injection pipe of the bottom is S2=215-(5×5+1.2×10+1.2×15)=160cm.

[0188] By adjusting the length of the flow guide pipe, a triangular buffer zone is formed at both ends of the length direction of the bottom;

[0189] Through this design, the time for the resin to reach the edge of the bottom in the length direction is prolonged, ensuring that the resin reaches the six edges of the bottom at the same time.

[0190] After the flow guide pipe on the bottom is laid, a horizontal and continuous ring-shaped flow guide pipe is laid every 40cm along the weft direction on the six vertical surfaces (only disconnected at the driver's room door);

[0191] Finally, a nylon peelable cloth edge extending 20cm beyond the glass fiber reinforced material is wound around a flow guide pipe for air extraction or glue outlet pipe, and a glue injection seat is fixed every 50cm on the flow guide pipe.

[0192] Then perform the splicing of the vacuum bag, first, lay a layer of mulch on the ground to protect the vacuum bag, and bond the two vacuum bags with sealing rubber strips. After splicing, wrap the vacuum bag with mulch and transport it to the production site;

[0193] Seal the vacuum bag with the sealing strip, and use a rolling pin to compact the vacuum bag and the sealing strip. Connect the vacuum pipeline, and draw the vacuum bag to a slightly tight state. Close the vacuum source, and bridge the bag;

[0194] Perform a pressure holding test, and after passing, insert the pipe and inject glue. Use transparent PU pipe for injection to facilitate observation of the glue injection process and detection of air leakage. The material is foldable and recyclable. Each injection seat requires a 1 m long PU pipe. Fold the PU pipe in a Z shape to prevent air leakage, and use paper tape to fix it. When the PU pipe needs to be opened, cut the paper tape, and the PU pipe needs to be folded for standby;

[0195] Then, cut an X-shaped small hole on the top of each injection seat 3 with scissors, and quickly insert the PU pipe into the injection seat. Then, wrap the root of the PU pipe with several turns of sealing tape and press it tightly. Swing the PU pipe to check if it leaks. Then, seal the vacuum bag again, and connect the vacuum system to start pumping.

[0196] At the same time, cut an X-shaped small hole on the corresponding position of the second layer vacuum bag, and pass the PU pipe on the first layer vacuum bag out. Wrap the root of the PU pipe with several turns of sealing tape and press it tightly. Swing the PU pipe to check if it leaks. If it leaks, wrap it with several turns of sealing tape and press it tightly.

[0197] Use a vacuum pump to perform vacuum pumping. A buffer tank needs to be connected between the vacuum pump and the buffer pipe to prevent resin backflow.

[0198] It should be noted that 1) The buffer tank is equipped with a pressure gauge, and the vacuum bag needs to be checked for leaks during vacuum pumping.

[0199] 2) After the vacuum is stable, close the buffer tank inlet valve. If the vacuum degree does not decrease within 10 minutes, it is qualified.

[0200] 3) After passing, continue to pump for more than 5 hours to further evacuate the air in the system.

[0201] When introducing resin again, it is necessary to introduce resin into the mold cavity through the pre-laid pipeline in a vacuum environment, so that the resin can fully infiltrate the fibers. During this process, it is necessary to control the flow rate and flow time of the resin to ensure that the resin can be evenly distributed and fully infiltrate the fibers.

[0202] According to the set injection sequence, perform injection. Stop injection when the resin reaches the edge of the mold. Fold all the injection PU pipes into a Z shape and fix them with paper tape. Perform room temperature curing. After solidification, continue to pump for 24 hours to prevent product deformation. Then, take the product out of the mold and perform subsequent processing to complete product production.

[0203] In summary, this invention accurately predicts the flow behavior of resin in complex geometries through CFD flow simulation, and dynamically optimizes the parameters of the flow guiding system based on the filling time cloud map and pressure distribution, such as the curvature-compensated length of the flow guiding pipe and the laying area of ​​the flow guiding net in the low-speed zone, to ensure that the resin preferentially wets the high-resistance area.

[0204] A layered flow guidance strategy is adopted in conjunction with a stress-guided layup design, including unidirectional flow channels, low-resistance flow guidance nets in the fabric area, and rounded corner decreasing layup, to simultaneously meet the requirements of structural performance and flow efficiency. The flow guidance effect is verified through flat plate experiments, step-by-step sealing control of the vacuum system, multi-inlet dynamic injection and gradient curing process, forming a complete closed-loop manufacturing process. This solves problems such as uneven flow and dry spot defects caused by fiber deformation in irregular structures, and significantly improves the molding quality and process reliability of composite material products.

[0205] The above description of the embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method of forming a composite profiled fast craft superstructure, characterised in that: The method comprises the following steps: S1, constructing a three-dimensional model based on the cab structure, performing resin flow simulation, and obtaining a flow guide analysis result; S2, calculating flow guide pipe parameters according to the simulated flow guide analysis result, and generating a flow guide system; S3, generating a layering table according to the flow guide analysis result of step S1 and the laying position of the flow guide net; S4, laying the fiber reinforced layer on the mold according to the layering table, and arranging the flow guide system at a predetermined position based on a layered laying strategy; S5, setting a resin flow experiment plate to verify the resin flow rate; S6, laying auxiliary materials on the fiber reinforced layer, extending and covering, and setting a vacuum bag to construct a vacuum system; S7, synchronously injecting resin through multiple inlets and dynamically adjusting the injection pressure; S8, curing the resin by using a gradient curing process and demolding to prepare a product.

2. The method of claim 1, wherein: In step S1, the resin flow simulation specifically comprises: inputting data parameters of the three-dimensional model and porosity of the fiber preform into a software model as data; setting material parameters based on material characteristics; defining boundary conditions, including resin inlet pressure, flow rate, outlet pressure, and contact angle; obtaining a flow guide analysis result through model simulation calculation.

3. A method of forming a composite profiled motor yacht superstructure as claimed in claim 2, wherein: The flow guide analysis result comprises: a filling time cloud map: identifying the last filled area to mark the potential dry spot position; a pressure distribution map: locating a high pressure difference area to mark an area needing flow guide optimization; a flow velocity vector map: used for checking resin flow around the area.

4. The method of claim 1, wherein: The flow guide pipe parameters comprise a flow guide pipe length and a flow guide net laying area; wherein the formula for calculating the flow guide pipe length is specifically: ； wherein: L is the flow guide pipe length; K is the permeability of the fiber pre-impregnated material; ΔP is the pressure difference; t is the target filling time; μ is the dynamic viscosity of the resin; Fiber porosity; C is the curvature correction coefficient.

5. A method of forming a composite profiled motor yacht superstructure as claimed in claim 4, characterised in that: extracting an area with a flow velocity lower than 50% of the average flow velocity from the simulation result as a flow guide net laying area, calculating the projection area Azone of the area through geometric modeling, Laying area of the guide net The calculation formula is specifically: ； wherein: is the flow compensation factor; is the overlap coefficient of the guide vanes.

6. The method of claim 1, wherein: The flow of step S3 specifically comprises: S31, converting the principal stress direction calculated by the software model into fiber orientation to obtain a layering analysis result; S32, dividing a profit area according to the stress cloud map, wherein the high stress area is subjected to thickening treatment; S33, setting a layering sequence according to the balance condition of the laminate and verifying the rationality of the layering sequence by using a stiffness matrix; S34, combining the flow guide system to optimize the layering sequence and generate a layering table.

7. A method of forming a composite profiled motor yacht superstructure according to claim 6, characterised in that: The step S34 specifically comprises: a unidirectional tape (UD) area is arranged with a narrow flow guide groove along the fiber direction; a fabric area is covered and arranged with a low resistance flow guide net; a round corner or curved surface area is layered in a decreasing manner to construct a natural flow channel; a high permeability medium is added at the junction of a thick area or a core material; the positions of resin injection ports and exhaust ports are set based on resin flow simulation.

8. The method of claim 1, wherein: In step S4, the layered laying strategy specifically comprises: for a fiber layer with a thickness > 5mm, a sandwich structure is used to set the flow guide net: the lower flow guide net covers 50% of the bottom area of the high resistance area; the middle layer is a thick fiber layer; the upper flow guide net covers 50% of the top area and is connected with the branch flow guide pipe.

9. The method of claim 1, wherein: The specific process of step S5 is: set a model plate with the same structure as the layering table and the flow guide system, which is consistent with the product; One half of the flat plate is provided with a flow guide net, and the other half is not provided with a flow guide net; Perform the perfusion operation and record the perfusion completion time on both sides of the flat plate; Verify the perfusion effect and adjust and optimize the flow guide system accordingly.

10. The method of claim 1, wherein: The flow of step SS6 is specifically as follows: S61, two vacuum bags are bonded with sealing rubber strips and sealed; S62, the vacuum bag is connected with the vacuum pipeline, the vacuum bag is extracted to be slightly tight, and the bridging process is performed; S63, the vacuum bag is pressure tested to verify the sealing qualification of the vacuum bag; S64, the intubation process is performed, and the buffer tank is connected, and then the buffer tank is connected to the vacuum pump; S65, the vacuum bag is sealed for the second time, and the vacuum bag and the sealing rubber strip are compacted; S66, vacuum extraction verification is performed.

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