Parabolic groove type condenser design method based on tolerance angle and condensation ratio analysis

Abstract

The invention relates to the technical field of solar energy utilization. The invention provides a parabolic trough condenser design method based on tolerance angle and condensation ratio analysis, a parabolic trough condenser comprises a reflecting surface and a receiver, and the method comprises the following steps: S1, introducing a tolerance angle as a main control parameter, and establishing an initial one-dimensional model of the parabolic trough condenser; s2, on the basis of the initial one-dimensional model, determining receiver diameters and reflecting surface opening widths corresponding to different tolerance angles, and calculating a condensation ratio; s3, performing function fitting processing on the corresponding data of the tolerance angle and the condensation ratio; s4, according to the function relationship, using the condensation ratio to inversely calculate a tolerance angle, and using the tolerance angle, the receiver diameter and the opening width to construct a target one-dimensional model; and S5, converting the target one-dimensional model into a three-dimensional model to obtain the required parabolic trough condenser structure. According to the method, the rapid design of the parabolic trough condenser can be realized without depending on complex manual operation and empirical value selection, and the method has relatively high engineering application value and popularization significance.

Description

Technical Field

[0001] This application relates to the field of solar energy utilization technology, and more specifically, to a design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis. Background Technology

[0002] Fossil fuels have long been the world's primary energy source, and with accelerated industrialization, the consumption of fossil fuels such as oil, natural gas, and coal has continued to increase. However, the excessive use of fossil fuels easily causes environmental pollution, and their reserves are limited, making it difficult to meet the energy needs of long-term sustainable development. Solar energy, as a clean and renewable energy source, has broad application prospects in addressing energy shortages and environmental problems.

[0003] Among solar energy utilization technologies, concentrated solar thermal utilization, concentrated photovoltaic power generation, and concentrated solar thermal power generation are the fastest-growing technological routes. Among these, the parabolic trough concentrator is a relatively mature concentrated solar thermal utilization device, which has been applied in fields such as solar thermal power generation, industrial heating, and seawater desalination. This type of concentrator typically consists of a parabolic reflector and a receiver located at the focal point. It utilizes the parabolic reflection principle to focus sunlight onto the receiver surface to achieve the collection and conversion of solar energy.

[0004] Existing parabolic trough solar concentrators mostly rely on solar tracking systems. These systems use control devices to rotate the reflector surface as the sun's position changes, maintaining the optimal angle between the incident light and the reflector surface to improve energy absorption efficiency. However, the addition of solar tracking systems increases the concentrator's structural complexity, manufacturing costs, and maintenance workload, and also places high demands on control precision. Furthermore, the design of existing concentrator structures typically requires complex optical parameter calculations, a time-consuming process that is difficult to implement quickly, hindering the widespread application of concentrators in practical engineering projects.

[0005] Therefore, there is an urgent need to propose a method for rapid and accurate design of parabolic trough concentrator geometry without relying on complex solar tracking systems, so as to simplify the design process, reduce costs and improve engineering applicability. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of the prior art by providing a design method for parabolic trough concentrators based on tolerance angle and concentration ratio analysis, thereby solving the problem of difficulty in quickly and accurately designing the geometric configuration of parabolic trough concentrators in the prior art.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This application provides a design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis. The parabolic trough concentrator includes a reflector and a receiver. The design method includes the following steps: S1. Introduce the tolerance angle as the main control parameter and establish an initial one-dimensional model of the parabolic trough concentrator in computer-aided design software; S2. Based on the initial one-dimensional model, determine the receiver diameter and the aperture width of the reflective surface corresponding to different tolerance angles, and calculate the light concentration ratio; S3. Perform function fitting on the corresponding data of tolerance angle and concentration ratio; S4. Based on the functional relationship, the tolerance angle is calculated using the concentration ratio, and a one-dimensional model of the target is constructed using the tolerance angle, receiver diameter, and aperture width. S5. Convert the target one-dimensional model into a three-dimensional model to obtain the required parabolic trough concentrator structure.

[0008] This application introduces the tolerance angle as the primary control parameter. Starting from the geometric relationship between light incidence and reflection, it directly limits the acceptable angle range of incident light using the tolerance angle, and determines geometric elements such as the parabola's focal point, vertex, and receiver position accordingly, ensuring that each tolerance angle value corresponds to a unique one-dimensional geometric configuration. As the tolerance angle increases, the incident light deviates more from the principal optical axis, requiring the parabola to have a wider opening and a larger receiver diameter to ensure that the reflected light can still be focused on the receiver. Conversely, as the tolerance angle decreases, the light tends to converge at the focal point, requiring a reduction in geometric dimensions to avoid energy loss. Through this geometric constraint mechanism, a stable single-valued function relationship is formed between the tolerance angle and the concentration ratio, allowing for precise control of the focusing performance by setting the tolerance angle. Based on this mechanism, this application transforms the previously experience-based geometric parameters into parameterized results generated by the tolerance angle, establishing a correspondence between the tolerance angle, geometric configuration, and concentration ratio. This fundamentally solves the technical problem of the difficulty in quickly and accurately obtaining a reasonable geometric structure in the design of existing parabolic trough concentrators.

[0009] Furthermore, in S1, initial one-dimensional models are established for different tolerance angles, including: drawing the incident and reflected rays at the corresponding tolerance angles in the coordinate system, determining the focal and vertex positions of the parabola, and drawing the symmetrical parabolic contour; determining the center of the receiver circle based on the intersection position of the reflected rays at the corresponding tolerance angle, and drawing a receiver circle tangent to the incident ray at the center position. This process can determine the geometric relationship between the curvature of the reflecting surface and the focal position in the initial stage of modeling, giving the model a unified optical constraint basis, and simultaneously determining the position and size of the receiver, so that the receiver range matches the convergence area of ​​the reflected rays.

[0010] Furthermore, the parabolic profile is symmetrical with respect to the second coordinate axis of the coordinate system, and the center of the receiver circle is set at the origin of the coordinate system. This feature establishes a unified geometric reference system, enabling the centering and positioning of the reflecting surface and the receiver.

[0011] Furthermore, in S2, the focusing ratio is the ratio of the aperture width to the product of the receiver diameter and pi.

[0012] Furthermore, in S3, a ray tracing calculation module is established based on the initial one-dimensional model to generate high-density tolerance angle-concentration ratio data points. The function relationship between the tolerance angle and the concentration ratio is then fitted based on these data points. This operation yields a more comprehensive data distribution, making the fitted curve closer to real optical behavior and reducing fitting bias caused by sparse sampling.

[0013] Furthermore, in S4, when calculating the corresponding value of the tolerance angle, a geometric proportional constraint is applied to the ratio of the opening width to the receiver diameter, and a target one-dimensional model is constructed under the condition that the proportional constraint is satisfied. This constraint can limit the range of variation of the model size, prevent the calculation of a geometrically abnormal model, and ensure that the inverse calculation result maintains a reasonable proportion.

[0014] Furthermore, in S5, converting the target one-dimensional model into a three-dimensional model includes: extruding the parabolic profile along its length to form a reflective surface; and extruding the receiver circle along its length to form a hollow tubular receiver. This operation generates reflective surfaces and receiver entities with actual thickness, facilitating subsequent mechanical strength analysis and manufacturing processes, and enabling efficient transfer of concentrated thermal energy.

[0015] Furthermore, in S5, the direction of the stretch modeling is the normal to the coordinate system plane, and the wall thickness offset direction is set to the side away from the origin.

[0016] Furthermore, the computer-aided design software is SOLIDWORKS.

[0017] Furthermore, the method also includes arranging multiple 3D models in a parallel array along their optical axes in computer-aided design software to construct concentrating system models of different scales. This arrangement increases the luminous flux per unit area of ​​the concentrator while facilitating modular expansion of the system.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) This application sets the tolerance angle as the main control parameter and establishes a one-dimensional model for different tolerance angles, thereby realizing the automatic generation of geometric configuration parameters. This avoids the problem of existing design methods relying on manual trial calculations and experience-based value selection, and greatly reduces the workload of repeated adjustments in the early stage of design.

[0019] (2) This application extracts key geometric parameters such as receiver diameter and reflector opening width under different tolerance angles, and establishes a functional relationship between tolerance angle and concentration ratio based on these data, so that the concentration performance evaluation can be realized in the early modeling stage, avoiding repeated testing with physical prototypes and improving the pertinence and efficiency of the design process.

[0020] (3) This application achieves rapid reverse derivation from target performance indicators to geometric configuration by using the fitted functional relationship to back-calculate the tolerance angle and construct the target one-dimensional model, shortening the iteration cycle of concentrator geometric design and improving the accuracy of scheme generation. Compared with general parabolic trough concentrators, the concentrator of this application has higher adaptability and can maintain efficient solar energy collection capabilities in more practical application scenarios, thereby improving energy utilization efficiency.

[0021] (4) This application uses computer-aided software to directly convert the target one-dimensional model into a three-dimensional model, so that the resulting geometric configuration can be seamlessly entered into the subsequent structural design and processing stage. This avoids the intermediate links such as model reconstruction and secondary size conversion in traditional methods, improves the continuity and integrity of the design chain, and has strong engineering adaptability and promotion value. Attached Figure Description

[0022] Figure 1 A flowchart illustrating a design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis provided by this invention; Figure 2 A schematic diagram of a parabolic trough concentrator based on tolerance angle and concentration ratio analysis provided by the present invention; Figure 3 A schematic diagram of a one-dimensional model of a parabolic trough concentrator based on tolerance angle and concentration ratio analysis provided by the present invention; Figure 4 This is a graph showing the characteristic relationship between tolerance angle and concentration ratio; Figure 5 for Figure 2 A schematic diagram of the focusing system behind the parabolic trough concentrator array.

[0023] Icons: 10 - Reflector; 20 - Receiver; 30 - Ring connector A; 40 - Ring connector B. Detailed Implementation

[0024] To make the implementation process of this invention clearer, a detailed description will be provided below in conjunction with the accompanying drawings.

[0025] Example 1: This invention provides a design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis, such as... Figure 1 As shown, the design method includes the following steps: S1. Introducing the tolerance angle as the main control parameter, an initial one-dimensional model of the parabolic trough concentrator is established in computer-aided design software; the parabolic trough concentrator includes a reflector 10 and a receiver 20, such as... Figure 2As shown, the reflective surface 10 is generally grooved, extending along the optical axis into a parabolic profile, used to reflect and converge incident sunlight to the focal region; the receiver 20 is cylindrical and installed at the focal position of the reflective surface 10, used to absorb the converged light energy. The reflective surface 10 is preferably made of aluminum alloy or stainless steel sheet, and its surface is coated with a high-reflectivity silver or aluminum film layer to ensure good light reflection performance and weather resistance; the receiver 20 preferably uses a high-temperature resistant metal tube (such as stainless steel or copper) as the substrate, its outer wall can be coated with a selective absorption coating to improve solar energy absorption rate, and its inner cavity can be equipped with a high-temperature resistant transparent glass sleeve to form a vacuum insulation layer, reducing heat loss and improving thermal efficiency. The curvature of the reflective surface 10 and the focal position are geometrically constrained by each other, and the focal position simultaneously determines the center position of the receiver 20; the two must satisfy the geometric relationship of the optical reflection law.

[0026] In this embodiment, SOLIDWORKS is preferably used as the computer-aided design software platform. Its sketching function allows for the intuitive drawing of incident and reflected ray paths in the coordinate system, accurately determining the focus and vertex of the parabola, and simultaneously placing the receiver 20 positions in the model, thus achieving the parametric construction of the one-dimensional model. The sketching only represents the cross-sectional outline in line form and does not include closed shapes with areas; therefore, the constructed model is a one-dimensional geometric model rather than a two-dimensional solid planar model.

[0027] In the modeling process of this embodiment, based on the laws of optical reflection and geometric properties, an xoy rectangular coordinate system is first established in SOLIDWORKS, such as... Figure 3 As shown, an arbitrary point A is selected in the positive x-axis direction as the incident point. Two incident rays, ray 1 and ray 2, are drawn from the upper left and upper right directions respectively, with an included angle of the set tolerance angle θ, representing the incident ray deflection caused by the change in the sun's azimuth. Then, the tangent and the normal to the tangent are drawn at the incident point A, where the tangent serves as an auxiliary reference, representing the local direction of the reflective surface 10 to be formed at A. Based on the law that the angle of incidence equals the angle of reflection, the reflected rays ray 3 and ray 4 corresponding to the incident rays ray 1 and ray 2 are drawn to determine the reflected light path.

[0028] Next, select any point on the reflected ray 4 of the incident ray 2, which travels from the upper right to the lower left, as the focus of the parabola. Draw a line segment parallel to the incident ray 2 at this focus, and use any point on this line segment as the vertex of the parabola. This parallel line segment is used to determine the axis of the parabola, ensuring that the axis is parallel to the incident light, thus satisfying the parabolic reflection property of "parallel incident axis, reflected through the focus." Using this focus and vertex as geometric conditions, generate a parabola in the fourth quadrant of the coordinate system using the "Parabola Draw" command in SOLIDWORKS software. Then, use the "Coincident" command to align the upper right endpoint of the parabola with the incident point A, fixing the position of the parabola and the ray, and ensuring that the true normal of the parabola at the incident point A coincides with the aforementioned auxiliary normal.

[0029] Subsequently, at any point on the lower left corner of the parabola as the incident point B, two incident rays 5 and 6 with an included angle of θ (i.e., two incident rays parallel to the incident point A) are drawn. A tangent and a normal are drawn at incident point B, and reflected rays 7 and 8 are drawn according to the law of reflection. The four reflected rays at incident points A and B are extended to obtain two intersection points formed by the reflected rays of the incident rays at the same time: the intersection of reflected ray 3 and reflected ray 7, and the intersection of reflected ray 4 and reflected ray 8. The midpoint of the line connecting the two intersection points is taken as the center of the receiver 20. This point is chosen because, under the condition of incident light at the same time (parallel to each other), the two boundary reflection lines formed by the reflections at incident points A and B give the two sides of the reflected beam under this incident direction. Taking the midpoint ensures that the cross-section of receiver 20 is centered and covers the reflected beam. Draw a circle of arbitrary size at the midpoint and place its center at the origin of the coordinate system. This will allow for accurate reading of the position of any point in the coordinate system where the concentrator geometry is located during subsequent design processes. Using the "Tangent" function in the "Line Properties," set the circle to be tangent to the incident ray 5 incident from the upper left to the lower right at the incident point B, thereby determining the position and size range of the receiver 20.

[0030] Finally, using the "Mirror Entity" function in SOLIDWORKS software, with the y-axis as the mirror axis, the parabola in the fourth quadrant is mirrored to generate the other half of the curve. This ensures that the one-dimensional geometric model of the parabolic trough concentrator is symmetrically closed in the lateral direction, completing the construction of the one-dimensional model for the set tolerance angle θ. By repeating the above process, corresponding one-dimensional geometric models can be established for different tolerance angles θ, providing a unified optical structural basis for subsequent geometric parameter extraction and concentration performance calculation.

[0031] S2. Based on the initial one-dimensional model, determine the diameter of the receiver 20 and the opening width of the reflector 10 corresponding to different tolerance angles, and calculate the light concentration ratio. After completing the construction of the initial one-dimensional model corresponding to different tolerance angles θ, use the measurement tools in SOLIDWORKS software to read the diameter of the receiver 20 circle and the horizontal distance between the two endpoints of the parabola in the initial one-dimensional model, which are respectively used as the diameter d of the receiver 20 and the opening width W of the reflector 10. When the tolerance angle θ increases, the convergence range of the reflected light expands, and the opening width W of the parabola needs to be increased and the diameter d of the receiver 20 needs to be increased to ensure that the light can be covered by the receiver 20. When the tolerance angle θ decreases, the reflected light tends to be concentrated, and the diameter d of the receiver 20 and the opening width W need to be reduced accordingly to avoid light energy leakage. By substituting the measured W and d parameters corresponding to different tolerance angle θ values ​​into the concentration ratio formula C=W / (πd), the concentration ratio C corresponding to different tolerance angle θ is calculated, realizing the quantitative correlation between tolerance angle, geometric parameters and concentration performance, and providing a data foundation for establishing the functional relationship between tolerance angle and concentration ratio in the future.

[0032] S3. Perform function fitting processing on the corresponding data of tolerance angle and concentration ratio; import the multiple sets of corresponding data of tolerance angle θ and concentration ratio C obtained in step S2 into data processing software, preferably Excel, and draw a scatter plot of tolerance angle θ and concentration ratio C to intuitively present the trend of concentration performance changing with tolerance angle. Then, use the curve fitting function in Excel to fit the scatter data in the form of polynomial or exponential functions to obtain a fitting curve that can accurately characterize the corresponding law of tolerance angle θ and concentration ratio C, and output its function expression.

[0033] In this embodiment, to improve the computational efficiency of the tolerance angle inverse calculation, a tolerance angle prediction module is preferably introduced before executing step S4. This module is trained based on a previously constructed sample dataset containing data corresponding to the tolerance angle, receiver diameter, reflector aperture width, and concentration ratio. Support Vector Regression (SVR) is preferably used to construct the prediction model, where the tolerance angle is the output variable, and the concentration ratio and related geometric parameters are the input features. After training, when a target concentration ratio is input, the model can output an approximate tolerance angle value corresponding to that concentration ratio. The predicted tolerance angle value is used as the initial solution for step S4, and then combined with a precise calculation process for inverse calculation to reduce the invalid search range and the number of iterations, thereby improving the convergence speed of the tolerance angle solution and the overall design efficiency.

[0034] S4. Based on the functional relationship, the tolerance angle is calculated using the concentration ratio. A target one-dimensional model is constructed using the tolerance angle, the diameter of receiver 20, and the aperture width. After obtaining the functional relationship between the tolerance angle θ and the concentration ratio C, the required target concentration ratio value is first input into the functional model. Based on the functional expression, the tolerance angle θ value corresponding to the target concentration ratio C is obtained. Subsequently, using this tolerance angle as the main control parameter, the geometric parameters are readjusted in SOLIDWORKS software based on the existing one-dimensional model: the curvature of the parabola and the aperture width W are changed to match the new focal point position, and the position and diameter d of the receiver 20 circle are simultaneously modified to ensure that the convergence range of the reflected light is consistent with the size of receiver 20. Through the above operations, the construction of the target one-dimensional model of the parabolic trough concentrator that meets the target concentration ratio requirements is completed.

[0035] S5. Convert the target 1D model into a 3D model to obtain the required parabolic trough concentrator structure. In SOLIDWORKS, select the parabolic profile in the target 1D model, and perform the "Extrude Boss / Base" operation on the sketch plane supporting the profile. The extrusion direction is the normal to the sketch plane (i.e., the trough length direction), and the extrusion length is set. "Symmetrical" extrusion is preferred so that the length is centered about the sketch plane. Simultaneously, enable the "Thin Wall Feature" and select "Single," offsetting the wall thickness to the side away from the focal point, so that the reflecting surface 10 on the focal point side coincides with the 1D parabola, thereby converting the parabolic profile into a 3D model structure of the reflecting surface 10 with solid thickness. Then, select the circular sketch of the receiver 20 in the target 1D model, and similarly perform the "Extrude Boss / Base" operation on the sketch plane, setting the extrusion length along the normal and enabling the "Thin Wall Feature." To ensure that the diameter of the circle in the one-dimensional model is the same as the inner diameter of receiver 20, the thin-wall offset direction is set away from the center of the circle, making the inner circular surface coincide with the one-dimensional sketch circle. This transforms the circular sketch into a hollow tubular three-dimensional model structure of receiver 20, ultimately obtaining the required parabolic trough concentrator structure. To maintain clarity in assembly and measurement, the stretching of reflector 10 and receiver 20 should form two independent solids. The stretching length, wall thickness, and other parameters of both should be assigned according to the design, and the center of receiver 20 should be kept consistent with the coordinate origin. Thus, the three-dimensional modeling of reflector 10 and receiver 20 is completed solely through stretching and thin-wall features, without the need to introduce other modeling features.

[0036] In practical applications, to verify the feasibility of the method of the present invention, a parabolic trough concentrator with a concentration ratio of 5 is designed as an example, and the specific operation is as follows: First, based on Figure 4The characteristic relationship curve between the tolerance angle and the concentration ratio was used to determine that the tolerance angle θ corresponding to a concentration ratio C=5 is 14°, and this value was used as the main control parameter for one-dimensional modeling. In SOLIDWORKS, an xoy rectangular coordinate system was established. An incident point A was arbitrarily selected in the positive x-axis direction, and two incident rays with an included angle of 14° were drawn. The corresponding reflected rays were then drawn according to the law of reflection. Subsequently, the focus and vertex of the parabola were selected to generate the parabola profile, and the incident point A was aligned with the endpoint of the parabola. An incident point B was set at the lower left of the parabola, and a group of parallel incident rays was drawn and their reflected rays were generated. The intersection point was obtained by extending the reflected rays, and the midpoint of the line connecting the intersection points was used as the center of receiver 20. A sketch of a circular receiver 20 with a diameter of 45mm was drawn. Using the "Mirror Solid" command, the other half of the parabola was generated with the y-axis as the axis of symmetry, resulting in the complete parabola profile and completing the one-dimensional model establishment.

[0037] Next, the parabolic profile was selected and the "Extrude Boss / Base" operation was performed. The extrusion length was set to 0.85m, and the "Thin Wall Feature" was enabled, setting the wall thickness to 2mm, resulting in a 3D model of the reflector 10 with a length of 1.7m. Simultaneously, the circular sketch of the receiver 20 was selected, the extrusion length was set to 0.9m, and the "Thin Wall Feature" was enabled, setting the thickness to 2mm, resulting in a hollow tubular receiver 20 with an outer diameter of 47mm and a length of 1.8m. To facilitate subsequent system integration, the reflector 10 and receiver 20 were set as independent entities, with the center of receiver 20 coinciding with the origin of the coordinate system, thus obtaining a parabolic trough-type concentrator structure with a concentration ratio of 5.

[0038] Example 2: Based on Example 1, this example optimizes the data acquisition process and parameter back-calculation process to improve the accuracy of the concentration ratio function fitting and the rationality of the target model construction. Specifically, the improvements include the following: In step S3 of Example 1, a ray tracing calculation module is added to the initial one-dimensional model to generate a high-density tolerance angle-concentration ratio data point set. This module, based on a one-dimensional geometric model built in the SOLIDWORKS environment, automatically emits multiple sets of parallel incident rays at set tolerance angle θ step intervals, records the intersection range of reflected rays, and calculates the corresponding receiver 20 diameter d and the opening width W of the reflecting surface 10. Then, the concentration ratio C is calculated using the formula C=W / (πd). This method yields a more comprehensive tolerance angle range and a higher resolution data distribution, making the subsequent curve fitting results in Excel closer to actual optical focusing behavior, reducing fitting deviations caused by sparse sampling, and thus improving the stability and reliability of the tolerance angle-concentration ratio function relationship.

[0039] In step S4 of Example 1, a proportional constraint mechanism is introduced during the geometric parameter inverse calculation process. After solving for the target tolerance angle θ based on the fitted functional relationship, a geometric constraint is applied to the proportional relationship between the diameter d of the receiver 20 and the opening width W of the reflective surface 10, limiting it to a preset reasonable range, such as controlling the W / d ratio to be within the range of engineering experience. This constraint avoids unreasonable extreme combinations of the receiver 20 diameter d and the opening width W of the reflective surface 10, prevents the generation of excessively wide or narrow parabolic groove curves, ensures that the target one-dimensional model obtained by inverse calculation conforms to actual manufacturing feasibility in terms of size proportions, and maintains the coordination and matching between optical performance and structural parameters.

[0040] By implementing any one or two of the above-mentioned improvement measures, this embodiment can increase the sampling density of data points and control the proportion of geometric parameters, making the fitted functional relationship more accurate and the model configuration more reasonable, thus providing a stable parameter basis for subsequent 3D model construction.

[0041] Example 3: Based on the three-dimensional model construction of the parabolic trough concentrator completed in Example 1, this example further combines multiple three-dimensional model units of parabolic trough concentrators into integrated concentrating system models of different scales by arranging them in an array, so as to realize the extended application of parabolic trough concentrators from single structures to overall systems.

[0042] Specifically, in SOLIDWORKS software, open the "Features" toolbar, select the existing 3D model of reflector 10 and receiver 20, select the "Linear Array" function, and in the pop-up "Linear Array" toolbar, select the x-axis as the array direction under the "Direction" option to make the optical axes of the parabolic trough concentrator parallel to each other. Set the array spacing to a range of 300-400mm to accommodate different focusing sizes, preferably 352.37mm. In this embodiment, the array quantity is set to 3, and the reflector 10 and receiver 20 models are selected in the "Features and Surfaces" option to generate three sets of 3D model units of the parabolic trough concentrator arranged at equal intervals. The overall layout is as follows: Figure 5 As shown, the axes (focal lines) of the reflecting surfaces 10 of the three sets of parabolic trough concentrator 3D model units are arranged in parallel and perpendicular to the xoy plane to ensure continuous alignment of the focusing focal area between the units. Through array arrangement operations, the original single models are transformed into a parallel overall layout, expanding the optical converging area of ​​the concentrating system.

[0043] After obtaining three sets of concentrating units arranged in parallel, this embodiment connects the three receiver 20 tubes through annular pipe connectors A 30 and B 40 to form a fluid channel, converting them into a series arrangement. Annular pipe connectors A 30 and B 40 are preferably made of high-temperature resistant stainless steel, and sealing rings and clamping structures are provided at the joints to ensure reliable sealing and coaxial communication with the receiver 20 ports. This series connection allows the fluid to pass through multiple receivers 20 sequentially, extending the heat transfer path length, increasing the heat transfer area and time per unit fluid, thereby improving the thermal output temperature of the concentrating system. Simultaneously, the arrayed parallel structure expands the overall optical focusing area, enabling the concentrating system to capture more incident irradiance, improving output power and operational stability.

[0044] By completing the array construction and channel connection operations in the three-dimensional design stage, the number and arrangement of concentrator units can be flexibly set according to actual application requirements. The series or parallel connection method can be selected according to the required output temperature and power, thereby forming a multi-level and multi-scale concentrating system, achieving the design goal of taking into account both high heat flux density and high power output in the same system.

[0045] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis, wherein the parabolic trough concentrator includes a reflector and a receiver, characterized in that: The method includes the following steps: S1. Introduce the tolerance angle as the main control parameter and establish the initial one-dimensional model of the parabolic trough concentrator in computer-aided design software; S2. Based on the initial one-dimensional model, determine the receiver diameter and the opening width of the reflective surface corresponding to different tolerance angles, and calculate the light concentration ratio; S3. Perform function fitting on the corresponding data of tolerance angle and concentration ratio; S4. Based on the functional relationship, the tolerance angle is calculated using the concentration ratio, and a one-dimensional model of the target is constructed using the tolerance angle, the receiver diameter, and the opening width. S5. Convert the target one-dimensional model into a three-dimensional model to obtain the required parabolic trough concentrator structure.

2. The design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis according to claim 1, characterized in that: In S1, the initial one-dimensional model is established for different tolerance angles, including: drawing the incident ray and reflected ray under the corresponding tolerance angle in the coordinate system, determining the focal position and vertex position of the parabola and drawing the symmetrical parabola outline; determining the center of the receiver circle according to the intersection position of the reflected ray under the corresponding tolerance angle, and drawing the receiver circle tangent to the incident ray at the center position.

3. The design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis according to claim 2, characterized in that: The parabolic profile is symmetrical with respect to the second coordinate axis of the coordinate system, and the center of the receiver circle is set at the origin of the coordinate system.

4. The design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis according to claim 3, characterized in that: In S2, the focusing ratio is the ratio of the aperture width to the product of the receiver diameter and pi.

5. The design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis according to claim 4, characterized in that: In S3, a ray tracing calculation module is established based on the initial one-dimensional model to generate high-density tolerance angle-concentration ratio data points, and the functional relationship between tolerance angle and concentration ratio is fitted according to the data points.

6. The design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis according to claim 5, characterized in that: In S4, when calculating the corresponding value of the tolerance angle, a geometric proportional constraint is applied to the ratio of the opening width to the receiver diameter, and the target one-dimensional model is constructed under the condition of satisfying the proportional constraint.

7. The design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis according to claim 6, characterized in that: In S5, converting the target one-dimensional model into the three-dimensional model includes: stretching the parabolic profile along the length direction to form the reflective surface; and stretching the receiver circle along the length direction to form the hollow tubular receiver.

8. The design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis according to claim 7, characterized in that: The direction of the stretching model is the normal to the coordinate system plane, and the wall thickness offset direction is set to the side away from the origin.

9. The design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis according to claim 1, characterized in that: The computer-aided design software is SOLIDWORKS.

10. The design method for a parabolic trough concentrator based on tolerance angle and concentration ratio analysis according to claim 1, characterized in that: The method further includes: arranging multiple three-dimensional models in a parallel array along their optical axes in the computer-aided design software to construct light-gathering system models of different scales.

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