Design method of non-rotation type overall inertia particle separator

Abstract

The invention discloses a design method of a non-rotation type integral inertia particle separator, which comprises the following steps: S1, establishing an XY coordinate system, and determining a plurality of key nodes on a meridian plane flow channel profile and coordinates of the key nodes; s2, setting a slope value for each key node; s3, calculating and generating a two-degree-of-freedom adjustable curve between two key nodes which need to be connected into a line; s4, calculating to obtain a two-degree-of-freedom adjustable curve between all the key nodes needing to be connected, and sequentially connecting to form a meridian plane runner molded surface of the non-rotation type overall inertia particle separator; and S5, rotating the meridian plane flow channel molded surface by 360 degrees by taking the x axis in the coordinate system as a rotating shaft to generate a rotating body, and obtaining a three-dimensional geometric configuration of the non-rotation type integral inertial particle separator. According to the method, a two-degree-of-freedom adjustable curve function is adopted, the shape of a curve between any adjacent key nodes can be freely changed by changing free parameters Oi, 1 and Oi and 2, and parameterization design research of the non-rotation type overall inertial particle separator can be more flexibly and rapidly carried out.

Description

Technical Field

[0001] The invention relates to the technical field of aeroengines, and in particular to a design method for a non-rotational integral inertial particle separator. Background Art

[0002] Aircraft engines are important components of aircraft and are known as the heart of aircraft. Turboshaft engines are a typical type of aircraft engines, which are mainly used in rotorcraft such as helicopters and tilt-rotor aircraft. Compared with fixed-wing aircraft, rotorcraft have advantages such as convenient take-off and landing, and hovering in the air, so they often perform missions in environments such as deserts, wilderness, and forests where runways are lacking. For this reason, turboshaft engines used in rotorcraft face a greater risk of inhaling sand and dust particles. Once a large number of sand and dust particles enter the engine core, the service life of the engine will be significantly shortened, or even directly damaged. In order to reduce the negative impact of sand and dust particles on the engine, advanced turboshaft engines are generally equipped with a particle separator upstream of the core engine, so as to discharge sand and dust particles out of the main flow channel as much as possible and reduce the damage caused by sand and dust particles.

[0003] Commonly used particle separators are mainly divided into three categories: intake barrier filters, vortex tube separators and non-rotating integral inertial particle separators. The intake barrier filter uses filter media to absorb solid particles, but it needs to be replaced frequently and has a short service life; the vortex tube separator uses the blades in the flow channel to generate vortices to roll sand and dust particles to the outside of the flow channel. The vortex tube separator requires a large windward area and installation volume, the structural economy is poor, and it causes a large total pressure loss; the non-rotating integral inertial particle separator does not require additional blades, has the advantages of light weight, small aerodynamic loss, and high reliability. It relies on its own curved bifurcated flow channel to induce sand and dust particles with large inertia to enter the sand discharge flow channel, thereby achieving the purpose of foreign matter removal.

[0004] Now combined with the attached Figure 1 Briefly explain the working principle of the rotation-free integral inertial particle separator: The flow channel profile of the rotation-free integral inertial particle separator is a forked curved flow channel. When air and sand and dust particles flow through the sharply curved flow channel, the air has a small inertia and can flow into the main channel in large quantities along the pipe profile, while the sand and dust particles have a large inertia and are difficult to enter the main channel with the air. Therefore, they are separated from the airflow, enter the scavenging channel, and are collected by the scavenging volute downstream of the scavenging channel and discharged from the engine.

[0005] Although the rotation-free integral inertial particle separator is mainly manifested as an axisymmetric body of revolution in three-dimensional geometry, that is, after designing the flow channel profile of the two-dimensional meridian plane, the three-dimensional configuration of the rotation-free integral inertial particle separator can be obtained by rotating it 360° around the x-axis, the high-performance design of the two-dimensional meridian plane itself is still very challenging due to its complex flow channel shape.

[0006] Existing design methods either highly rely on commercial modeling software or use excessive design parameters to describe the flow channel profile on the meridian plane, making it difficult to carry out rapid and flexible parametric design. In addition, in specific engineering projects, the design of the flow channel profile of the particle separator must also be compatible with the engine structure. Therefore, sometimes it is required that the flow channel profile of the particle separator passes through specific points, or the position of a certain local part on the flow channel cannot be changed. Existing design methods are difficult to meet the above design constraints.

[0007] Therefore, a new parametric design method needs to be proposed, which can not only conveniently determine the flow channel profile on the meridian plane according to geometric parameters with clear physical meanings, but also quickly change the design parameters to realize the update and adjustment of the flow channel profile. Summary of the Invention

[0008] Objective of the Invention: Aiming at the above shortcomings, the present invention provides a design method for a non-rotating integral inertial particle separator.

[0009] Technical Solution: To solve the above problems, the present invention adopts a design method for a non-rotating integral inertial particle separator, including the following steps:

[0010] S1. Establish an XY coordinate system and determine several key nodes on the flow channel profile of the meridian plane. The coordinates of the key nodes are (x1, f1), (x2, f2)…(x i , f i ), (x i+1 , f i+1 );

[0011] S2. Set slope values f'1, f'2…f' i , f' i+1 for each key node;

[0012] S3. Calculate and generate a two-degree-of-freedom adjustable curve between two key nodes to be connected into a line. The function of the two-degree-of-freedom adjustable curve is as follows:

[0013] y = α0(t)f i + α1(t)f i+1 + β0(t)h i f' i + β1(t)h i f' i+1

[0014] Where:

[0015]

[0016] h i = x i+1 - x

[0017] t = (x - xi ) / h i

[0018] O i,1 ,O i,2 is a free adjustment coefficient; α0(t), α1(t), β0(t), and β1(t) are adjustable basis functions;

[0019] S4. Calculate the double-degree-of-freedom adjustable curves between all the key nodes to be connected, and connect all the obtained double-degree-of-freedom adjustable curves in sequence to form the meridian plane flow channel profile of the non-rotating integral inertial particle separator;

[0020] S5. Rotate the meridian plane flow channel profile 360° around the x-axis in the coordinate system to generate a solid of revolution, and obtain the three-dimensional geometric configuration of the non-rotating integral inertial particle separator.

[0021] Furthermore, the meridian plane flow channel profile includes a mixed flow channel profile, a sweep air flow channel profile bifurcated from the mixed flow channel profile, and a main flow channel profile. The flow channel surrounded by the sweep air flow channel profile is used to separate sand and dust particles, and the flow channel surrounded by the main flow channel profile is used for the air flow to pass through.

[0022] Furthermore, the distance between the two key nodes farthest apart in the x-axis direction is equal to the length of the air inlet channel.

[0023] Furthermore, the value range of the ordinate of the key node at the upper end face of the throat of the mixed flow channel profile is 1.1 - 1.8R 扫气流道 ,R 扫气流道 is the ordinate of the key node at the upper end face of the sweep air flow channel profile.

[0024] Furthermore, the number of the key nodes is 15 - 20.

[0025] Furthermore, the slope value is an arbitrary constant.

[0026] Furthermore, the O i,1 ,O i,2 is an arbitrary constant.

[0027] The present invention also provides a computer device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the steps of the above method are implemented.

[0028] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above method are implemented.

[0029] Beneficial effects: Compared with the prior art, the significant advantage of the present invention is that it adopts a double-degree-of-freedom adjustable curve function. By changing the free parameter Oi,1 ,O i,2 makes the shape of the curve between any adjacent key nodes change accordingly on the premise that the key nodes and the node slopes are determined, enabling a more flexible and rapid parametric design study of the non-rotating integral inertial particle separator. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is the working principle of the non-rotating integral inertial particle separator;

[0031] Figure 2 is a schematic diagram of the key nodes of the non-rotating integral inertial particle separator of this embodiment;

[0032] Figure 3 is a schematic diagram of the meridional plane flow passage profile of this embodiment;

[0033] Figure 4 is a schematic diagram of the three-dimensional geometric configuration of the non-rotating integral inertial particle separator;

[0034] Figure 5 is the C-sand separation efficiency diagram of the non-rotating integral inertial particle separator of this embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] A design method for a non-rotating integral inertial particle separator in this embodiment includes the following steps:

[0036] S1. Establish an XY coordinate system and determine several key nodes on the meridional plane flow passage profile. In this embodiment, the meridional plane flow passage profile includes a mixed flow passage profile, a swept gas flow passage profile bifurcated from the mixed flow passage profile, and a main flow passage profile. The flow passage surrounded by the swept gas flow passage profile is used to separate sand and dust particles, and the flow passage surrounded by the main flow passage profile is used for the gas to pass through. The number of key nodes on the meridional plane flow passage profile is 15 - 20.

[0037] Among them, the first group of key nodes A - F to be connected in sequence are a total of six key nodes, the second group of key nodes are N - R, a total of five key nodes, and the third group of key nodes are G - M, a total of seven key nodes. As Figure 2 shown, the first group of key nodes A - F are the design points of the outer surface profile of the center body of the meridional plane flow passage profile. The second group of key nodes N - R are the design points of the outer cover surface profile of the meridional plane flow passage profile, and the third group of key nodes G - M are the design points of the bifurcated flow passage profile of the meridional plane flow passage profile.

[0038] The coordinates of several relatively important key nodes can be determined according to the engine structure and design experience. For example, the distance between the two key nodes (A and F) with the farthest interval in the x-axis direction is equal to the length of the intake duct; the ordinate value range of the key node O at the upper end surface of the throat of the mixed flow passage profile is 1.1 - 1.8R扫气流道 , R 扫气流道 is the ordinate of the key node on the upper end surface of the swept gas flow channel, and the width at the throat is smaller than the width at the inlet, that is, h BO is less than h AN .

[0039] First, determine the coordinates of six key nodes in the first group of key nodes as (x A , f A ), (x B , f B ), …, (x E , f E ), (x F , f F ). Specifically, in this embodiment, the coordinates of the first group of key nodes are A(0, 157), B(53, 182), C(100, 125), D(201, 51), E(294, 39), F(483, 39) in sequence.

[0040] S2. Set slope values f' A , f' B … f' E , f' F for each key node. In this embodiment, the slope values of each key node are set as f' A = 0.768, f' B = 0, f' C = -1.43, f' D = -0.316, f' E = f' F = 0

[0041] The slope values can be set to any constant, and curves connecting adjacent points can be obtained subsequently. However, generally, more appropriate slope values are set for each key node according to experience to make the finally formed meridian flow channel profile have better effects.

[0042] S3. Calculate and generate a two-degree-of-freedom adjustable curve between two key nodes to be connected into a line. The two-degree-of-freedom adjustable curve function is as follows:

[0043] y = α0(t)f i + α1(t)f i+1 + β0(t)h i f' i + β1(t)h i f' i+1

[0044] Where:

[0045]

[0046] hi = x i+1 -x

[0047] t = (x - x i ) / h i

[0048] O i,1 , O i,2 is a free adjustment coefficient; α0(t), α1(t), β0(t), β1(t) are adjustable basis functions.

[0049] In the AB curve of this embodiment, O i,1 = O i,2 = 0; In the BC curve, O i,1 = 0.2, O i,2 = 0; In the CD curve, O i,1 = O i,2 = -1; In the DE curve, O i,1 = O i,2 = 0; In the EF curve, O i,1 = O i,2 = 0

[0050] The free adjustment coefficient can be set to any real number, and a curve connecting adjacent two points can be obtained. Generally, a more appropriate free adjustment coefficient will be set according to experience, so that the finally formed meridional flow passage profile has a better effect. Taking the double-degree-of-freedom adjustable curve between two points N and O on curve L2 as an example, the free parameter values of the black solid line are O i,1 = O i,2 = 0, and the free parameter values of the red dashed line are O i,1 = O i,2 = 10. That is, when the values of O i,1 and O i,2 are different, the shape of the curve between any adjacent key nodes can also change on the premise that the key nodes and the node slopes are fixed.

[0051] S4. Calculate the double-degree-of-freedom adjustable curve between the remaining key nodes to be connected on this curve, and connect them to form the meridional flow passage profile of the non-rotating integral inertial particle separator.

[0052] Specifically, the coordinates of the five key nodes N - R of the second group of key nodes are N(0, 197), O(57, 210), P(163, 175), Q(261, 175), R(359, 175) in sequence. The slope values set for N - R are f' N = 0.353, f' O = f' P = f' Q = f' R = 0. The O of the NO curve i,1, O i,2 The values are all 0, and the O of the OP curve i,1 , O i,2 The values are 0.2 and 0 respectively, and the O of the PQ curve i,1 , O i,2 The values are all 0, and the O of the QR curve i,1 , O i,2 The values are all 0.

[0053] The coordinates of the seven key nodes G - M on the third group of key nodes are G(359, 163), H(259, 163), I(160, 163), J(112, 163), K(110, 161), L(294, 98), M(483, 98) in sequence. The slope values set for G - M are f' G = f' H = f' I = f' J = 0, f' K = ∞, f' L = f' M = 0. The O of the GH curve i,1 , O i,2 The values are all 0, and the O of the HI curve i,1 , O i,2 The values are all 0, and the O of the IJ curve i,1 , O i,2 The values are all 0, and the O of the JK curve i,1 , O i,2 The values are all 0, and the O of the KL curve i,1 , O i,2 The values are 2 and -0.2 respectively, and the O of the LM curve i,1 , O i,2 The values are all 0. Calculate the curve function between two key nodes to be connected according to the method in step S3, and finally obtain the curve functions between all key nodes to be connected, forming a complete meridional flow channel profile.

[0054] S5. Rotate the meridional flow channel profile 360° around the x - axis in the coordinate system to generate a rotating body, and obtain the three - dimensional geometric configuration of the non - rotating integral inertial particle separator.

[0055] The efficiency of the non - rotating integral inertial particle separator designed by the above method for separating C - sand (Arizona coarse dust) is measured through experiments, as Figure 5 shown, where the scavenging ratio refers to the ratio of the gas flow rate containing particles to be removed to the total inlet gas flow rate entering the separator. It is detected that the designed non - rotating integral inertial particle separator can meet the actual engineering design requirements.

Claims

1. A method for designing a non-rotational integral inertial particle separator, characterized in that: The following steps are involved: S1. Establish an XY coordinate system and determine several key nodes on the meridian flow channel profile. The coordinates of the key nodes are (x1, f1), (x2, f2)…(x i ,f i )、(x i+1 ,f i+1 ); S2. Set the slope value f'1, f'2...f' for each key node i 、f' i+1 ; S3. Calculate and generate a dual-degree-of-freedom adjustable curve between two key nodes to be connected into a line. The dual-degree-of-freedom adjustable curve function is as follows: y=α0(t)f i +α1(t)f i+1 +β0(t)h i f' i +β1(t)h i f' i+1 in: h i =x i+1 -x t=(x-x i ) / h i O i,1 , O i,2 is the free adjustment coefficient; α0(t), α1(t), β0(t), β1(t) are adjustable basis functions; S4, calculating and obtaining the double-degree-of-freedom adjustable curves between all the key nodes to be connected, and sequentially connecting all the obtained double-degree-of-freedom adjustable curves to form a meridian flow channel profile of the irrotational integral inertial particle separator; S5. Rotate the meridian flow channel profile 360° with the x-axis in the coordinate system as the rotation axis to generate a rotating body, thereby obtaining a three-dimensional geometric configuration of the non-rotational integral inertial particle separator.

2. The method for designing a non-rotational integral inertial particle separator according to claim 1, characterized in that: The meridian flow channel profile includes a mixing flow channel profile, a scavenging flow channel profile formed by bifurcation of the mixing flow channel profile, and a main flow channel profile. The flow channel formed by the scavenging flow channel profile is used to separate sand and dust particles, and the flow channel formed by the main flow channel profile is used for airflow to pass through.

3. The method for designing a non-rotational integral inertial particle separator according to claim 2, characterized in that: The distance between the two key nodes farthest apart in the x-axis direction is equal to the length of the inlet duct.

4. The method for designing a non-rotational integral inertial particle separator according to claim 2, characterized in that: The vertical coordinate value range of the key node at the upper end of the throat of the mixing channel profile is 1.1~1.8R 扫气流道 , R 扫气流道 It is the ordinate of the key node on the upper end surface of the scavenging channel profile.

5. The method for designing a non-rotational integral inertial particle separator according to claim 1, characterized in that: The number of the key nodes is 15-20.

6. The method for designing a non-rotational integral inertial particle separator according to claim 1, characterized in that: The slope value is an arbitrary constant.

7. The method for designing a non-rotational integral inertial particle separator according to claim 1, characterized in that: The O i,1 , O i,2 is an arbitrary constant.

8. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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