Sliding type flow distribution adjusting device and method for aviation
By using a pure mechanical structure with a sliding flow distribution adjustment device in the aviation control system, the problem of weight, complexity and control lag in existing systems is solved, and higher system reliability and lower energy consumption are realized Essence
Patent Information
- Application Number
- CN202411582635.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-07
- Publication Date
- 2025-01-24
AI Technical Summary
In the existing aviation fluid control systems, the electric flow regulating valve and flow detection device have weight, complexity and control hysteresis problems, and it is difficult to work effectively in an on-board environment.
A sliding flow distribution adjustment device with a purely mechanical structure is used to drive the adjustment plate to move through the strip blade cascade and the support mechanism to change the flow cross-section of the two outlets to achieve flow adjustment. The device includes an inlet housing, a flow detection mechanism, a support mechanism, an elastic element, a flow regulating mechanism and an outlet housing.
The system complexity and weight are reduced, the number of regulating components is reduced, the system reliability is improved, the control hysteresis and fluctuations are improved, and the energy consumption of the power source in the liquid system is reduced.
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Figure CN119353446A_ABST
Abstract
Description
[0001] Technical field: The present invention belongs to the field of fluid control technology, and specifically relates to a sliding flow distribution and adjustment device and method for aviation. Background Art
[0002] In the field of aircraft fluid control, in order to achieve the optimal performance of the system with liquid as the working fluid, the flow distribution ratio of different branches needs to be adjusted according to the system flow at the pipeline branch. For the flow regulation requirements of fluid branches in closed pipeline systems, the current mainstream method is to set an electric flow control valve on the branch or at the branch position, arrange a flow detection device and a control device in the system, and the control device sends a corresponding opening instruction to the electric flow control valve based on the liquid flow signal fed back by the flow detection device. The electric flow control valve changes its opening to achieve flow distribution regulation of different branches.
[0003] This method has the following disadvantages: when using a flow control valve for adjustment, each branch needs to be equipped with a separate control valve, which is not conducive to improving the system integration; the control valve uses throttling to adjust the flow, which brings about a large flow resistance loss, which is not conducive to aircraft weight reduction and increases the power consumption of the liquid power source; automatic adjustment requires each flow control valve to be equipped with an electric or hydraulic drive mechanism, and a set of parameter detection and control systems are set up, which increases the weight and complexity of the system, and there is a control lag problem. Specifically in the aviation field, for working conditions that require flow as the control input, due to the strict weight restrictions and strong electromagnetic interference of the airborne environment, flow sensors cannot be arranged on the aircraft, and pressure parameters can only be used under specific conditions to approximately replace flow parameters. This method is difficult to adapt to real working conditions. In order to further reduce the number of components and reduce weight while improving system reliability, technical innovation is needed. Summary of the invention
[0004] The objects of the present invention are:
[0005] The invention discloses a sliding flow distribution regulating device and method for aviation. In an aircraft fluid system with branches, purely mechanical structural components are used to replace electric flow regulating valves, equivalent flow detection devices and control devices used to adjust flow distribution, thereby reducing the number of components, improving system reliability, improving control lag, and reducing system weight.
[0006] To solve this technical problem, the technical solution of the present invention is:
[0007] An aviation sliding flow distribution and adjustment device is used, comprising an inlet shell, a flow detection mechanism, a support mechanism, an elastic element, a flow adjustment mechanism, and an outlet shell; the liquid flow detection mechanism is a strip blade arranged perpendicular to the incoming flow direction, the strip blade is fixedly connected to the side of the support mechanism close to the incoming flow away from the incoming flow direction, and the side of the support mechanism away from the incoming flow is fixedly connected to the flow adjustment mechanism; the flow adjustment mechanism is a plate-like structure, comprising an adjustment plate and a boss; the adjustment plate is in sliding contact with two outlets on the inner side of the outlet shell on the side facing away from the incoming flow direction, and is limited and guided by two guide bosses on the inner side of the inlet shell, and can reciprocate along the line connecting the midpoints of the two outlets.
[0008] Furthermore, a plurality of blades are arranged in parallel on the strip cascade, and the blades are arranged without airfoils along the chord line at an angle of attack to the incoming flow, or with airfoils along the chord line at no angle to the incoming flow.
[0009] Furthermore, the elastic element is arranged between the boss and one of the guide bosses, and it should be ensured that the elastic element is always in a compressed state during the entire movement stroke.
[0010] Furthermore, the supporting mechanism is a rod-shaped structure, which is arranged along the incoming flow direction and supports the strip blade grid at a position in front of the outlet that is times the outlet equivalent pipe diameter.
[0011] Furthermore, two side surfaces of the regulating plate covering the two outlet positions are respectively provided with centrally shaped notches, and the portion where the notches overlap with the outlets forms an effective flow passage.
[0012] Furthermore, a damping plate is arranged on the contact side between the adjustment plate and the outlet shell, and the damping plate is a raised plate-like structure. A damping groove arranged along the movement direction of the adjustment plate is arranged at the contact part between the outlet shell and the adjustment plate. The damping plate extends into the damping groove to divide the space inside the damping groove into two parts. The contour of the damping plate is the same as the cross-section of the damping groove, and a small gap is maintained.
[0013] When the incoming liquid flows through the strip blades, the strip blades are subjected to a hydraulic force perpendicular to the incoming flow direction and directed to the back side of the blades, and the regulating plate is driven by the supporting mechanism to move in the form of a gate along the center line of the two outlets. At this time, the special-shaped notches on the edges of the regulating plate and the effective flow cross-section formed by the two outlets change simultaneously. When the flow area of one outlet increases, the flow area of the other outlet decreases accordingly, thereby realizing flow regulation of the two outlets.
[0014] The distribution and regulation of the two outlet flows is determined by the area ratio required for the two outlets when the flow detection mechanism and the flow regulation mechanism are in a specific equilibrium position, and the flow cross-sectional area is larger than the flow cross-sectional area required for regulation by throttling the minimum flow outlet, thereby achieving a lower regulation resistance.
[0015] During the movement of the adjusting plate, the damping plate squeezes the liquid on one side of the damping groove through the gap between the damping plate and the damping groove to the other side of the damping groove, thereby achieving a damping effect and preventing the adjusting plate from swinging frequently near the equilibrium position.
[0016] A sliding flow distribution and adjustment method for aviation, comprising the following steps:
[0017] 1. The flow rates of the two outlets a and b are Qa and Qb respectively, and the total inlet flow rate is Q; the spring stiffness is k;
[0018] 2. The required flow distribution relationship between the two outlets a and b is described by the following formula:
[0019]
[0020] 3. The strip blade is subjected to lift F1 at the inlet flow rate Q1. At this time, the outlet flow rate of a is Qa1, the outlet flow rate of b is Qb1, and when the inlet flow rate increases by a small increment δQ, the increase in lift is:
[0021]
[0022] The upward displacement of the adjustment plate is recorded as δx, which is expressed as follows:
[0023]
[0024] At this time, the length and width of the corresponding outlet b that is not blocked by the special-shaped slot is recorded as y, and the effective area changes of the two outlets a and b are:
[0025] δA a =-(L a -y)·x (3)
[0026] δA b =L b ·x (4)
[0027] For the flow change, taking x as the independent variable for integral calculation, we have
[0028]
[0029] Combined with the known effective area A of outlets a and b when there is no flow in the example a0 and A b0 , by combining the above equations (1) to (5), we can obtain y=f(x), and the shape of the irregular notch can be determined.
[0030] The technical effects of the present invention are:
[0031] The flow distribution and adjustment device of the present invention is arranged at the branch of the pipeline of the liquid pipe network branch system. The fluid flows through the blade grid, and the blade grid generates lateral lift, which drives the adjustment plate to move through the support mechanism, changes the flow cross-section of the two outlets, and realizes continuous adjustment of different branch flow distribution ratios. The greater the fluid flow rate, the greater the force on the blade grid, and the more the adjustment plate moves, corresponding to different outlet flow distribution conditions. The flow distribution and adjustment device can reduce the complexity of the adjustment system, reduce the flow resistance caused by the flow distribution adjustment, and thus reduce the energy consumption of the power source in the liquid system. At the same time, the device can reduce the number of adjustment components, reduce the cost of the fluid adjustment device, improve the system reliability, improve the control lag and control fluctuation, and reduce the system weight. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Figure 1 It is a schematic diagram of the structure of the flow distribution and regulation device of the present invention;
[0033] Figure 2 It is a front view of the inner cavity of the outlet housing of the present invention;
[0034] Figure 3 A schematic diagram of a special-shaped notch on the adjustment plate of the present invention;
[0035] Figure 4 It is a schematic diagram of the cooperation between the special-shaped notch and the outlet of the present invention;
[0036] Figure 5 It is a schematic diagram of the design dimensions of the special-shaped notch of the present invention;
[0037] Wherein: 1-inlet shell, 2-flow detection mechanism, 3-support mechanism, 4-elastic element, 5-flow regulating mechanism, 6-outlet shell, 101-guide boss, 201-strip blade grid, 202-blade, 501-adjusting plate, 502-boss, 503-damping plate, 504-special-shaped notch, 601-outlet, 602-damping groove. DETAILED DESCRIPTION
[0038] In order to make the purpose, technical scheme and advantages of the implementation of the present invention clearer, the technical scheme in the embodiment of the present invention will be described in more detail in combination with the embodiment of the present invention. In the example, the same or similar reference numerals throughout represent the same or similar originals or elements with the same or similar functions. The described embodiments are part of the embodiments of the present invention, not all of them. The embodiments described below by reference are exemplary and intended to be used to explain the present invention, and should not be construed as limitations on the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present invention. The following is a detailed description in combination with the embodiments of the present invention.
[0039] The invention discloses a sliding flow distribution and regulating device for aviation, comprising an inlet shell 1, a flow detection mechanism 2, a support mechanism 3, an elastic element 4, a flow regulating mechanism 5, and an outlet shell 6; the liquid flow detection mechanism 2 is a strip blade 201 arranged perpendicular to the incoming flow direction, the strip blade 201 is fixedly connected to the side of the support mechanism 3 close to the incoming flow away from the incoming flow direction, and the side of the support mechanism 3 away from the incoming flow is fixedly connected to the flow regulating mechanism 5; the flow regulating mechanism 5 is a plate-like structure, comprising an adjusting plate 501 and a boss 502; the adjusting plate 501 is in sliding contact with two outlets 601 on the inner side of the outlet shell 6 on the side facing away from the incoming flow direction, and is limited and guided by two guide bosses 101 on the inner side of the inlet shell 1, and can make reciprocating motion along the line connecting the midpoints of the two outlets 601.
[0040] In a certain embodiment of the present invention, a plurality of blades 202 are arranged in parallel on the strip cascade 201. The blades 202 are blades without airfoils arranged at an angle of attack with the incoming flow according to the chord line, or blades with airfoils arranged at no angle with the incoming flow according to the chord line. Preferably, blades with airfoils are used to reduce the flow resistance of the components.
[0041] In a certain embodiment of the present invention, the elastic element 4 is disposed between the boss 502 and one of the guide bosses 101 , and it should be ensured that the elastic element 4 is always in a compressed state during the entire movement stroke.
[0042] In a certain implementation case of the present invention, the support mechanism 3 is a rod-shaped structure, arranged along the incoming flow direction, and supports the strip blade cascade 201 at a position three times the outlet equivalent pipe diameter in front of the outlet 601 .
[0043] In a certain implementation case of the present invention, two sides of the adjustment plate 501 covering the two outlet positions are respectively provided with centrally shaped notches 504 , and the portion where the notches 504 overlap with the outlet 601 forms an effective flow passage.
[0044] In a certain embodiment of the present invention, a damping plate 503 is arranged on the contact side of the adjustment plate 501 and the outlet shell 6. The damping plate 503 is a raised plate-like structure. A damping groove 602 arranged along the movement direction of the adjustment plate is arranged at the contact part between the outlet shell 6 and the adjustment plate 501. The damping plate 503 extends into the damping groove 602 to divide the space inside the damping groove 602 into two parts. The contour of the damping plate 503 is the same as the cross-section of the damping groove 602, and a small gap is maintained.
[0045] When the incoming liquid flows through the strip blade cascade 201, the strip blade cascade 201 is subjected to a liquid force perpendicular to the incoming flow direction and directed to the back side of the blade, and the regulating plate 501 is driven by the supporting mechanism 3 to move in the form of a gate along the center line of the two outlets 601. At this time, the effective flow cross-section formed by the special-shaped notches 504 on the edges of the regulating plate 501 on both sides and the two outlets 601 changes at the same time. When the flow area of one outlet 601 increases, the flow area of the other outlet 601 decreases accordingly, thereby realizing flow regulation of the two outlets 601.
[0046] The distribution and regulation of the flow at the two outlets 601 is determined by the area ratio required by the two outlets when the flow detection mechanism 2 and the flow regulation mechanism 5 are in a specific equilibrium position, and the flow cross-sectional area is larger than the flow cross-sectional area required for regulation by throttling the minimum flow outlet, thereby achieving a lower regulation resistance.
[0047] During the movement of the adjustment plate 501, the damping plate 503 squeezes the liquid on one side of the damping groove 602 through the gap between the damping plate 503 and the damping groove 602 to the other side of the damping groove 602, thereby achieving a damping effect and preventing the adjustment plate 501 from swinging frequently near the equilibrium position.
[0048] A sliding flow distribution and adjustment method for aviation, comprising the following steps:
[0049] 1. Let the flow rates of the two outlets 601 a and b be Qa and Qb respectively, and the total inlet flow rate be Q; the spring stiffness is k;
[0050] 2. The required flow distribution relationship between the two outlets a and b is described by the following formula:
[0051]
[0052] 3. The strip blade 201 is subjected to lift F1 at the inlet flow rate Q1. At this time, the outlet flow rate a is Qa1, the outlet flow rate b is Qb1, and when the inlet flow rate increases by a small increment δQ, the increase in lift is:
[0053]
[0054] The upward displacement of the adjustment plate is recorded as δx, which is expressed as follows:
[0055]
[0056] At this time, the length and width of the corresponding outlet b that is not blocked by the special-shaped notch 504 is recorded as y, and the effective area changes of the two outlets a and b are:
[0057] δA a =-(L a -y)·x (3)
[0058] δA b =L b ·x (4)
[0059] For the flow change, taking x as the independent variable for integral calculation, we have
[0060]
[0061] Combined with the known effective area A of outlets a and b when there is no flow in the example a0 and A b0 By combining the above equations (1) to (5), we can obtain y=f(x), and the shape of the irregular notch 504 can be determined.
[0062] The main body of the liquid flow detection mechanism 2 is a strip-shaped blade cascade 201, and the blade cascade 201 includes a plurality of blades 202 arranged side by side at a certain interval perpendicular to the incoming flow direction. The blades 202 are arranged at a certain angle of attack with the incoming flow according to the chord line using non-airfoil blades, or arranged at no angle with the incoming flow according to the chord line using airfoil blades. Preferably, an airfoil form is adopted to improve the lift-to-drag ratio and reduce the flow resistance to a lower level under the premise of achieving the same driving force;
[0063] The support mechanism 3 is a rod-shaped structure, arranged along the incoming flow direction, and supports the strip blade cascade 201 at a position three times the outlet equivalent pipe diameter in front of the outlet 601 to prevent the flow field at the strip blade cascade 201 from being disturbed by the outlet;
[0064] The flow regulating mechanism 5 is approximately plate-shaped, and includes an adjusting plate 501 and a boss 502; the adjusting plate 501 is in sliding contact with the two outlets 601 on the inner side of the outlet housing 6 on the side facing away from the incoming flow direction, and is limited and guided by the two guide bosses 101 on the inner side of the inlet housing 1, and can reciprocate along the line connecting the midpoints of the two outlets 601; when the incoming liquid flows through the strip blade 201, the strip blade 201 is subjected to a hydraulic force perpendicular to the incoming flow direction and directed to the back side of the blade, and the adjusting plate 501 is driven by the supporting mechanism 3 to move in the form of a gate along the center line connecting the two outlets 601. At this time, the special-shaped notches 504 on the edges of both sides of the adjusting plate 501 and the effective flow cross-section formed by the two outlets 601 change simultaneously. When the flow area of one outlet 601 increases, the flow area of the other outlet 601 decreases accordingly, thereby realizing the flow regulation of the two outlets 601;
[0065] The distribution and regulation of the flow rates of the two outlets 601 is determined by the area ratio of the two outlets when the flow detection mechanism 2 and the flow regulation mechanism 5 are at a specific equilibrium position, and the flow cross-sectional area is greater than the flow cross-sectional area required for regulation by throttling the minimum flow outlet, thereby achieving a lower regulation resistance;
[0066] A damping plate 503 is provided on the contact side between the adjustment plate 501 and the outlet housing 6. The damping plate 503 is a raised plate-like structure. A damping groove 602 arranged along the movement direction of the adjustment plate is provided on the contact portion between the outlet housing 6 and the adjustment plate 501. The damping plate 503 extends into the damping groove 602 to divide the space inside the damping groove 602 into two parts. The contour of the damping plate 503 is the same as the cross section of the damping groove 602, and a small gap is maintained. During the movement of the adjustment plate 501, the damping plate 503 squeezes the liquid on one side of the damping groove 602 through the gap between the damping plate 503 and the damping groove 602 to the other side of the damping groove 602, thereby achieving a damping effect and preventing the adjustment plate 501 from swinging frequently near the equilibrium position.
[0067] The elastic element 4 is used to provide a restoring force for the flow regulating mechanism 5. The elastic element 4 is disposed between the boss 502 and one of the guide bosses 101. The elastic element 4 is always in a compressed state during the entire movement stroke.
[0068] The movement direction of the flow distribution mechanism 5 is perpendicular to the flow direction of the liquid at the two outlets 601, so as to eliminate the impact force generated by the liquid flow on the flow distribution mechanism 5 to affect the force balance of the elastic element 4, thereby interfering with the flow distribution result;
[0069] There are three flow distribution points in this embodiment: 1. When the inlet flow is 800L / h, the a outlet flow is required to be 200L / h and the b outlet flow is 600L / h; 2. When the inlet flow is 900L / h, the a outlet flow is required to be 200L / h and the b outlet flow is 700L / h; 3. When the inlet flow is 1000L / h, the a outlet flow is required to be 200L / h and the b outlet flow is 800L / h. The spring stiffness coefficient is 1.11N / mm, and when the inlet flow is 800L / h, the strip blade lift is 4N, and the outlets 601 are all squares with a side length of 10mm. According to the design method of the present invention, when the inlet flow rate is 800L / h, the adjustment plate is displaced by 3mm relative to the initial position of 0 flow rate, the effective area of outlet a is 25.67mm^2, and the effective area of outlet b is 77mm^2; when the inlet flow rate is 900L / h, the adjustment plate is displaced by 4.06mm relative to the initial position of 0 flow rate, the effective area of outlet a is 24.73mm^2, and the effective area of outlet b is 86.56mm^2; when the inlet flow rate is 1000L / h, the adjustment plate is displaced by 4.725mm relative to the initial position of 0 flow rate, the effective area of outlet a is 24.31mm^2, and the effective area of outlet b is 97.25mm^2. The effective flow cross-sectional area ratio of the two outlets at the three design points a and b is consistent with the flow requirement ratio, and multi-point automatic distribution can be achieved.
[0070] Since the driving force change of the regulating device is directly derived from the liquid flow rate, there is no need for parameter collection and control logic feedback control, and therefore the control lag disadvantage unique to PID control does not exist.
[0071] It is understood by those skilled in the art that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of ordinary technicians in the field to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and unless defined as here, will not be interpreted with idealized or overly formal meanings. The specific implementation methods described above further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the present invention. Within the spirit and principle of the present invention, any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment of equivalent changes for application in other fields, but any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the technical solution content of the present invention, any modification, equivalent replacement, improvement, etc., made according to the technical essence of the present invention, should be included in the protection scope of the present invention.
Claims
1. A sliding flow distribution and adjustment device for aviation, characterized in that: It includes an inlet shell, a flow detection mechanism, a support mechanism, an elastic element, a flow regulation mechanism, and an outlet shell; the liquid flow detection mechanism is a strip blade arranged perpendicular to the incoming flow direction, the strip blade is fixedly connected to the side of the support mechanism close to the incoming flow away from the incoming flow direction, and the side of the support mechanism away from the incoming flow is fixedly connected to the flow regulation mechanism; the flow regulation mechanism is a plate-like structure, including an adjustment plate and a boss; the adjustment plate is in sliding contact with the two outlets on the inner side of the outlet shell on the side facing away from the incoming flow direction, and is limited and guided by two guide bosses on the inner side of the inlet shell, and can reciprocate along the line connecting the midpoints of the two outlets.
2. The device according to claim 1, characterized in that A plurality of blades are arranged in parallel on the strip cascade. The blades are arranged at an angle of attack with the incoming flow according to the chord line using blades without airfoils, or arranged at no angle with the incoming flow according to the chord line using blades with airfoils.
3. The device according to claim 2, characterized in that The elastic element is arranged between the boss and one of the guide bosses, and it should be ensured that the elastic element is always in a compressed state during the entire movement stroke.
4. The device according to claim 3, characterized in that The support mechanism is a rod-shaped structure, arranged along the incoming flow direction, and supports the strip blade grid at a position in front of the outlet that is outside the equivalent pipe diameter of the outlet.
5. The device according to claim 4, characterized in that The two sides of the regulating plate covering the two outlet positions are respectively provided with centrally shaped notches, and the portion where the notches overlap with the outlets forms an effective flow passage.
6. The device according to claim 5, characterized in that A damping plate is arranged on the contact side between the adjusting plate and the outlet shell. The damping plate is a raised plate-like structure. A damping groove arranged along the movement direction of the adjusting plate is arranged at the contact part between the outlet shell and the adjusting plate. The damping plate extends into the damping groove to divide the space inside the damping groove into two parts. The contour of the damping plate is the same as the cross-section of the damping groove, and a small gap is maintained.
7. The device according to claim 6, characterized in that When the incoming liquid flows through the strip blades, the strip blades are subjected to a hydraulic force perpendicular to the incoming flow direction and directed to the back side of the blades, and the regulating plate is driven by the supporting mechanism to move in the form of a gate along the center line of the two outlets. At this time, the special-shaped notches on the edges of the regulating plate and the effective flow cross-section formed by the two outlets change simultaneously. When the flow area of one outlet increases, the flow area of the other outlet decreases accordingly, thereby realizing flow regulation of the two outlets.
8. The device according to claim 7, characterized in that The distribution and regulation of the two outlet flows is determined by the area ratio required for the two outlets when the flow detection mechanism and the flow regulation mechanism are in a specific equilibrium position, and the flow cross-sectional area is larger than the flow cross-sectional area required for regulation by throttling the minimum flow outlet, thereby achieving a lower regulation resistance.
9. The device according to claim 8, characterized in that During the movement of the adjusting plate, the damping plate squeezes the liquid on one side of the damping groove through the gap between the damping plate and the damping groove to the other side of the damping groove, thereby achieving a damping effect and preventing the adjusting plate from swinging frequently near the equilibrium position.
10. The sliding flow distribution and adjustment method of the device according to claim 1, characterized in that: The steps include:
1. The flow rates of the two outlets a and b are Qa and Qb respectively, and the total inlet flow rate is Q; the spring stiffness is k; 2. The required flow distribution relationship between the two outlets a and b is described by the following formula:
3. The strip blade is subjected to lift F1 at the inlet flow rate Q1. At this time, the outlet flow rate of a is Qa1, the outlet flow rate of b is Qb1, and when the inlet flow rate increases by a small increment δQ, the increase in lift is: The upward displacement of the adjustment plate is recorded as δx, which is expressed as follows: At this time, the length and width of the corresponding exit b that is not blocked by the special-shaped slot is recorded as y, and the effective area changes of the two exits a and b are: δA a =-(L a -y)·x (3) δA b =L b ·x (4) For the flow change, taking x as the independent variable for integral calculation, we have Combined with the known effective area A of outlets a and b when there is no flow in the example a0 and A b0 , by combining the above equations (1) to (5), we can obtain y=f(x), and the shape of the irregular notch can be determined.