CN114021262B - Design method of three-channel front diffuser - Google Patents
Design method of three-channel front diffuser Download PDFInfo
- Publication number
- CN114021262B CN114021262B CN202111369477.3A CN202111369477A CN114021262B CN 114021262 B CN114021262 B CN 114021262B CN 202111369477 A CN202111369477 A CN 202111369477A CN 114021262 B CN114021262 B CN 114021262B
- Authority
- CN
- China
- Prior art keywords
- flow path
- diffuser
- inlet
- calculating
- front diffuser
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 34
- 238000011084 recovery Methods 0.000 claims abstract description 18
- 230000003068 static effect Effects 0.000 claims abstract description 17
- 238000002485 combustion reaction Methods 0.000 description 8
- 230000008901 benefit Effects 0.000 description 3
- 230000018109 developmental process Effects 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 230000004323 axial length Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/15—Vehicle, aircraft or watercraft design
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/17—Mechanical parametric or variational design
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
- G06F2119/14—Force analysis or force optimisation, e.g. static or dynamic forces
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
- G06F2119/20—Design reuse, reusability analysis or reusability optimisation
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Geometry (AREA)
- Theoretical Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- General Engineering & Computer Science (AREA)
- Mathematical Optimization (AREA)
- Computational Mathematics (AREA)
- Mathematical Analysis (AREA)
- Pure & Applied Mathematics (AREA)
- Aviation & Aerospace Engineering (AREA)
- Automation & Control Theory (AREA)
- Aerodynamic Tests, Hydrodynamic Tests, Wind Tunnels, And Water Tanks (AREA)
- Developing Agents For Electrophotography (AREA)
Abstract
The application belongs to the field of aeroengine combustors, and particularly relates to a design method of a three-channel front diffuser. The method comprises the steps of obtaining flow distribution data of a preposed diffuser, and respectively determining the inlet area and the inlet height of each flow path according to the flow distribution data; selecting parameters of each flow path according to the flow distribution data; dividing each flow path into a plurality of units with cross sections perpendicular to the center line along the center line, and calculating the length of each unit; calculating an outlet effective factor of each flow path; determining the area ratio iteration initial value of each flow path; calculating design parameters G of each flow path; calculating the equivalent effective factors of the inlets of the flow paths; calculating the maximum static pressure recovery coefficient of each unit of each flow path; calculating the ratio of the outlet section area to the inlet section area of each unit of each flow path, judging whether the ratio meets the requirement, if so, entering the next step, and if not, returning to the fifth step to re-determine the initial value of area ratio iteration; the inner and outer wall flow path dimensions of each flow path are determined.
Description
Technical Field
The application belongs to the field of aeroengine combustors, and particularly relates to a design method of a three-channel front diffuser.
Background
The diffuser is a main functional part in the combustion chamber and is mainly used for converting high-speed airflow at the outlet of the gas compressor into uniform low-speed airflow, reducing flow loss in the process to the maximum extent and ensuring smooth organization and combustion in the flame tube. Through development and improvement for many years, the diffuser is gradually changed from a pneumatic diffuser into a short sudden-expansion diffuser, a three-channel diffuser, a vortex-controlled diffuser and other advanced diffusion forms, and can well meet the development requirements of a combustion chamber. The three-channel diffuser diffusion mode has very obvious advantages on shortening the design length of the combustion chamber and reducing the flow loss of the existing high-temperature-rise combustion chamber, and is also one of the main hotspots of the current diffuser research.
The existing three-channel diffuser still belongs to a relatively new diffuser technology in the aspect of domestic application, and a design method is relatively deficient in the design of an initial scheme of a three-channel preposed diffuser; for a given overall design requirement, it is difficult to quickly form a three-channel diffuser design.
Accordingly, a technical solution is desired to overcome or at least alleviate at least one of the above-mentioned drawbacks of the prior art.
Disclosure of Invention
The present application is directed to a method of designing a three-channel front diffuser to address at least one of the problems of the prior art.
The technical scheme of the application is as follows:
a method of designing a three-channel front diffuser, comprising:
the method comprises the following steps of firstly, obtaining flow distribution data of a front diffuser, and respectively determining the inlet areas and the inlet heights of an outer flow path, a middle flow path and an inner flow path of the front diffuser according to the flow distribution data;
selecting parameters of an outer flow path, a middle flow path and an inner flow path of the front diffuser according to the flow distribution data;
dividing an outer flow path, a middle flow path and an inner flow path of the front diffuser into a plurality of units with cross sections perpendicular to the center line along the center line, and calculating the length of each unit;
step four, calculating the outlet effective factors of the outer flow path, the middle flow path and the inner flow path of the front diffuser;
determining area ratio iteration initial values of an outer flow path, a middle flow path and an inner flow path of the front diffuser;
calculating design parameters G of an outer flow path, a middle flow path and an inner flow path of the front diffuser;
step seven, calculating the inlet equivalent effective factors of the outer flow path, the middle flow path and the inner flow path of the front diffuser;
step eight, calculating the maximum static pressure recovery coefficient of each unit of the outer flow path, the middle flow path and the inner flow path of the front diffuser;
step nine, calculating the ratio of the outlet section area to the inlet section area of each unit of the outer flow path, the middle flow path and the inner flow path of the front diffuser, judging whether the ratio meets the requirement, if so, entering the next step, and if not, returning to the step five to re-determine the initial iteration value of the area ratio;
and step ten, determining the sizes of the inner and outer wall flow paths of the outer flow path, the middle flow path and the inner flow path of the front diffuser.
In at least one embodiment of the present application, in the step one, the obtaining flow distribution data of the pre-diffuser, and determining inlet areas and inlet heights of the outer flow path, the middle flow path, and the inner flow path of the pre-diffuser according to the flow distribution data respectively includes:
obtaining flow distribution data of a front diffuser, and obtaining mass flow W of the air flow flowing to an outer ring of the front diffuser according to the flow distribution data of the front diffuser O Gas flow mass flow W at the head of the flame tube M And inner ring air flow mass flow rate W i ；
Outer flow path inlet area A of front diffuser 3O The area A of the inlet of the intermediate flow path 3M And the inlet area A of the inner flow path 3i The following relationship exists:
A 3o :A 3M :A 3i ＝W o ：W M ：W i
obtaining:
wherein,
external flow path inlet based on pre-diffuserMouth area A 3O The area A of the inlet of the intermediate flow path 3M And the inlet area A of the inner flow path 3i Respectively determining the inlet height H of the outer flow path of the pre-diffuser 3O Intermediate flow path inlet height H 3M And an internal flow path inlet height H 3i 。
In at least one embodiment of the present application, in the second step, the selecting parameters of the outer flow path, the middle flow path, and the inner flow path of the pre-diffuser according to the flow distribution data includes:
selecting according to the flow distribution data:
outer flow path center line corner alpha of front diffuser difO Center line rotation angle alpha of intermediate flow path difM And inner flow path center line angle alpha difi ；
Outer flow path length L of front diffuser preO Intermediate flow path length L preM And inner flow path length L prei ；
Blockage ratio B of outer flow path inlet of front diffuser O Intermediate flow path inlet blockage ratio B M And internal flow path inlet blockage ratio B i 。
In at least one embodiment of the present application, in step three, the dividing the outer flow path, the middle flow path, and the inner flow path of the pre-diffuser into a plurality of units having cross sections perpendicular to the center line along the center line, and calculating the length of each unit includes:
the outer flow path, the middle flow path and the inner flow path of the front diffuser are divided into K along the central line O 、K M 、K i A unit with a section perpendicular to the centre line, the length S of each unit being:
S O ＝L preo /K O
S M ＝L preM /K M
S i ＝L prei /K i 。
wherein, K O 、K M 、K i The value of (A) ensures that the length S of each unit is about 1 mm.
In at least one embodiment of the present application, in step four, the calculating the outlet efficaciousness factors of the outer flow path, the intermediate flow path, and the inner flow path of the pre-diffuser includes:
calculating the effective factor E of the outer flow path outlet of the preposed diffuser 2O Intermediate flow path exit efficaciousness factor E 2M And inner flow path exit effectivity factor E 2i ：
E 2O ＝1-0.183(L gapo /H 30 ) 0.408 B o 0.315
E 2M ＝1-0.183(L gapM /H 3M ) 0.408 B M 0.315
E 2i ＝1-0.183(L gapi /H 3i ) 0.408 B i 0.315 。
In at least one embodiment of the present application, in step five, the determining the area ratio iteration initial values of the outer flow path, the middle flow path and the inner flow path of the pre-diffuser includes:
determining initial value AR of outer flow path area ratio iteration of pre-diffuser 30 Intermediate flow path area ratio iterative initial value AR 3M And initial value AR of inner flow path area ratio iteration 3i 。
In at least one embodiment of the present application, in step six, the calculating the design parameters G of the outer flow path, the middle flow path, and the inner flow path of the pre-diffuser includes:
calculating the outer flow path design parameter G of the pre-diffuser O Design parameters G of intermediate flow path M And inner flow path design parameters G i *：
G O * ＝E 2O 2 (0.985AR 3O 1.93 -1) -0.5
G M * ＝E 2M 2 (0.985AR 3M 1.93 -1) -0.5
G i * ＝E 2i 2 (0.985AR 3i 1.93 -1) -0.5 。
In at least one embodiment of the present application, in step seven, the calculating the inlet equivalent effective factors of the outer flow path, the middle flow path and the inner flow path of the pre-diffuser includes:
calculating the equivalent effective factor E of the outer flow path inlet of the preposed diffuser 1O Intermediate flow path inlet equivalent effective factor E 1M And an equivalent effective factor E of an inlet of the internal flow path 1i ：
When E is 2O 、E 2M 、E 2i >0.825 hour:
E 1O ＝1-0.0123E 2O -14.025 AR 3O -4
E 1M ＝1-0.0123E 2M -14.025 AR 3M -4
E 1i ＝1-0.0123E 2i -14.025 AR 3i -4
when E is 2O 、E 2M 、E 2i When the content is less than or equal to 0.825:
E 1O ＝1-0.0448E 2O -6.723 AR 3O -4
E 1M ＝1-0.0448E 2M -6.723 AR 3M -4
E 1i ＝1-0.0448E 2i -6.723 AR 3i -4 。
in at least one embodiment of the present application, in step eight, the calculating the maximum static pressure recovery coefficient of each unit of the outer flow path, the middle flow path and the inner flow path of the pre-diffuser includes:
calculating the maximum static pressure recovery coefficient of each unit of the outer flow path of the front diffuser
Maximum static pressure recovery coefficient of each unit of intermediate flow path
And maximum static pressure recovery coefficient of each unit of the inner flow path
In at least one embodiment of the present application, in step nine, the calculating a ratio of an outlet cross-sectional area to an inlet cross-sectional area of each of the cells of the outer flow path, the intermediate flow path, and the inner flow path of the pre-diffuser includes:
outlet cross-sectional area a of each cell of the outer flow path O(J+1) And the inlet cross-sectional area A O(J) The ratio of (A) to (B) is:
cross-sectional area A of outlet of each cell of intermediate flow path M(J+1) And the inlet cross-sectional area A M(J) The ratio of (A) to (B) is as follows:
outlet cross-sectional area a of each unit of the inner flow path i(J+1) And the inlet cross-sectional area A i(J) The ratio of (A) to (B) is:
the invention has at least the following beneficial technical effects:
according to the design method of the three-channel front diffuser, the G parameter method is adopted, the maximum static pressure recovery coefficient of each flow path of the front diffuser is effectively guaranteed, the molded surface parameters of each flow path of the three-channel front diffuser can be quickly formed, and the design of the initial performance scheme of the three-channel front diffuser is completed.
Drawings
FIG. 1 is a flow chart of a three-channel pre-diffuser design method according to one embodiment of the present application;
FIG. 2 is a schematic view of a three-channel front diffuser according to one embodiment of the present application.
Wherein:
1-outer flow path of front diffuser; 2-the center line of the outer flow path of the preposed diffuser; 3-middle flow path of the prepositive diffuser; 4-center line of middle flow path of the preposed diffuser; 5-flow path in the front diffuser; 6-center line of the internal flow path of the preposed diffuser; 7-height of inlet of outer flow path of front diffuser 3O (ii) a 8-middle flow path inlet height H of front diffuser 3M (ii) a 9-flow path inlet height H in inlet of pre-diffuser 3i (ii) a 10-outer flow path sudden expansion gap L gapO (ii) a 11-outer flow path centerline Angle of rotation α difO (ii) a 12-intermediate flow path sudden expansion gap L gapM (ii) a 13-center line rotation angle of intermediate flow path α difM (ii) a 14-inner flow path sudden expansion gap L gapi (ii) a 15-inner flow path central line corner alpha difi (ii) a 16-flame tube outer cap; and 17-inner cap cover of flame tube.
Detailed Description
In order to make the implementation objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are a subset of the embodiments in the present application and not all embodiments in the present application. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application and should not be construed as limiting the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application. Embodiments of the present application will be described in detail below with reference to the accompanying drawings.
In the description of the present application, it is to be understood that the terms "central," "longitudinal," "lateral," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the drawings, which are based on the orientation or positional relationship shown in the drawings, and are used for convenience in describing the present application and for simplicity in description, but do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore should not be construed as limiting the scope of the present application.
The present application is described in further detail below with reference to fig. 1-2.
The application provides a design method of a three-channel front diffuser, which comprises the following steps:
acquiring flow distribution data of a front diffuser, and respectively determining the inlet areas and the inlet heights of an outer flow path, a middle flow path and an inner flow path of the front diffuser according to the flow distribution data;
selecting parameters of an outer flow path, a middle flow path and an inner flow path of the front diffuser according to the flow distribution data;
dividing an outer flow path, a middle flow path and an inner flow path of the front diffuser into a plurality of units with cross sections perpendicular to the center line along the center line, and calculating the length of each unit;
step four, calculating the outlet effective factors of the outer flow path, the middle flow path and the inner flow path of the front diffuser;
determining area ratio iteration initial values of an outer flow path, a middle flow path and an inner flow path of the front diffuser;
calculating design parameters G of an outer flow path, a middle flow path and an inner flow path of the front diffuser;
step seven, calculating the inlet equivalent effective factors of the outer flow path, the middle flow path and the inner flow path of the front diffuser;
step eight, calculating the maximum static pressure recovery coefficient of each unit of the outer flow path, the middle flow path and the inner flow path of the front diffuser;
step nine, calculating the ratio of the outlet section area to the inlet section area of each unit of the outer flow path, the middle flow path and the inner flow path of the front diffuser, judging whether the ratio meets the requirement, if so, entering the next step, and if not, returning to the step five to re-determine the initial iteration value of the area ratio;
and step ten, determining the sizes of the inner and outer wall flow paths of the outer flow path, the middle flow path and the inner flow path of the front diffuser.
The design method of the three-channel preposed diffuser disclosed by the application is shown in figure 2, shows main design parameters related to the design of the pneumatic scheme of the three-channel preposed diffuser and the related pneumatic structure thereof, and mainly comprises a preposed diffuser outer flow path 1, a preposed diffuser outer flow path central line 2, a preposed diffuser middle flow path 3, a preposed diffuser middle flow path central line 4, a preposed diffuser inner flow path 5, a preposed diffuser inner flow path central line 6 and a preposed diffuser outer flow path inlet height H 3O 7. Front diffuser middle flow path inlet height H 3M 8. Flow path inlet height H in front diffuser 3i 9. Outer flow path sudden expansion gap L gapO 10. Outer flow path center line corner alpha difO 11. Intermediate flow path sudden expansion gap L gapM 12. Center line rotation angle alpha of intermediate flow path difM 13. Inner flow path sudden expansion gap L gapi 14. Inner flow path center line corner alpha difi 15. A flame tube outer cap cover 16 and a flame tube inner cap cover 17.
According to the design method of the three-channel preposed diffuser, firstly, flow distribution data of the three-channel preposed diffuser in the combustion chamber are obtained according to a flow path distribution scheme of the combustion chamber, and mass flow W of airflow flowing to an outer ring of the preposed diffuser is obtained according to the flow distribution data O Gas flow mass flow W at the head of the flame tube M And inner ring airflow mass flow W i (ii) a In the design, the area A of the outer flow path of the three-channel preposed diffuser is ensured O The intermediate flow passage area A M And inner flow area A i The ratio of the mass flow W to the mass flow of the gas entering the outer annular cavity of the combustion chamber O Flame tube head gas flow mass flowW M And inner ring cavity airflow mass flow W i The ratio of the ratio is the same.
A 3o :A 3M :A 3i ＝W o ：W M ：W i
On the basis, the inlet area A of the outer flow path corresponding to the front diffuser is determined 3O The area A of the inlet of the intermediate flow path 3M Inner flow path inlet area A 3i ：
Obtaining:
wherein,
according to the outer flow path inlet area A of the front diffuser 3O The area A of the inlet of the intermediate flow path 3M And the inlet area A of the inner flow path 3i Respectively determining the inlet height H of the outer flow path of the pre-diffuser 3O Intermediate flow path inlet height H 3M And an internal flow path inlet height H 3i 。
In the three-channel pre-diffuser design method, in the second step, the selection of parameters of an outer flow path, a middle flow path and an inner flow path of the pre-diffuser according to the flow distribution data comprises the following steps:
selecting according to the flow distribution data:
outer flow path center line corner alpha of front diffuser difO Center line rotation angle alpha of intermediate flow path difM And inner flow path center line angle alpha difi ；
Outer flow path length L of front diffuser preO Intermediate flow path length L preM And an internal flow path length L prei ；
Blockage ratio B of outer flow path inlet of front diffuser O Intermediate flow path inlet blockage ratio B M And internal flow path inlet blockage ratio B i 。
According to the design method of the three-channel preposed diffuser, the outer flow path center line corner alpha of the three-channel preposed diffuser is determined according to the flow path design result of the three-channel diffuser difO Center line rotation angle alpha of intermediate flow path difM Inner flow path central line corner alpha difi (ii) a Outer flow path length L preO Sudden expansion gap L gapO Intermediate flow path length L preM Sudden expansion gap L gapM Length of inner flow path L prei Sudden expansion gap L gapi (ii) a Inlet blockage ratio B of preposed diffuser of outer flow path O Middle flow path leading diffuser inlet blockage ratio B M Inlet blockage ratio of leading diffuser in inner flow path B i Outer flow path sudden expansion gap L of sudden expansion section gapO Intermediate flow path sudden expansion gap L gapM Inner flow path sudden expansion gap L gapi . The design principle of the center lines of the outer flow path and the inner flow path of the three-channel preposed diffuser is to ensure that the air flows at the outlets of the outer flow path and the inner flow path can be well attached to the surfaces of the flame tube outer cap 16 and the flame tube inner cap 17; the center line of the middle flow path of the three-channel diffuser is tangential to the center line of the flame tube as much as possible, so that the air flow at the inlet of the flame tube cap cover is prevented from overflowing.
In the third step, dividing the outer flow path, the middle flow path and the inner flow path of the front diffuser into a plurality of units with cross sections perpendicular to the center line along the center line, and calculating the length of each unit comprises:
the outer flow path, the middle flow path and the inner flow path of the front diffuser are divided into K along the central line O 、K M 、K i A unit with a section perpendicular to the centre line, the length S of each unit being:
S O ＝L preo /K O
S M ＝L preM /K M
S i ＝L prei /K i 。
wherein, K O 、K M 、K i The value of (A) ensures that the length S of each unit is about 1 mm.
In the fourth step, calculating the effective factors of the outlets of the outer flow path, the middle flow path and the inner flow path of the pre-diffuser comprises:
calculating the effective factor E of the outer flow path outlet of the preposed diffuser 2O Intermediate flow path exit effectiveness factor E 2M And inner flow path exit effectivity factor E 2i ：
E 2O ＝1-0.183(L gapo /H 30 ) 0.408 B o 0.315
E 2M ＝1-0.183(L gapM /H 3M ) 0.408 B M 0.315
E 2i ＝1-0.183(L gapi /H 3i ) 0.408 B i 0.315 。
In the fifth step, determining the area ratio iteration initial values of the outer flow path, the middle flow path and the inner flow path of the pre-diffuser comprises:
determining an initial value AR of an iteration of an outer flow path area ratio of a pre-diffuser 30 Intermediate flow path area ratio iterative initial value AR 3M And initial value AR of inner flow path area ratio iteration 3i 。
In the sixth step, calculating the design parameters G of the outer flow path, the intermediate flow path and the inner flow path of the pre-diffuser includes:
calculating the outer flow path design parameter G of the pre-diffuser O Design parameters G of intermediate flow path M And inner flow path design parameters G i *：
G O * ＝E 2O 2 (0.985AR 3O 1.93 -1) -0.5
G M * ＝E 2M 2 (0.985AR 3M 1.93 -1) -0.5
G i * ＝E 2i 2 (0.985AR 3i 1.93 -1) -0.5 。
In the seventh step, calculating the effective factors of the inlet equivalent of the outer flow path, the middle flow path and the inner flow path of the pre-diffuser comprises:
calculating the equivalent effective factor E of the outer flow path inlet of the preposed diffuser 1O Intermediate flow path inlet equivalent effective factor E 1M And an equivalent effective factor E of an inlet of the internal flow path 1i ：
When E is 2O 、E 2M 、E 2i >0.825 hour:
E 1O ＝1-0.0123E 2O -14.025 AR 3O -4
E 1M ＝1-0.0123E 2M -14.025 AR 3M -4
E 1i ＝1-0.0123E 2i -14.025 AR 3i -4
when E is 2O 、E 2M 、E 2i When the content is less than or equal to 0.825:
E 1O ＝1-0.0448E 2O -6.723 AR 3O -4
E 1M ＝1-0.0448E 2M -6.723 AR 3M -4
E 1i ＝1-0.0448E 2i -6.723 AR 3i -4 。
in step eight, the step of calculating the maximum static pressure recovery coefficient of each unit of the outer flow path, the middle flow path and the inner flow path of the pre-diffuser comprises the following steps:
calculating the maximum static pressure recovery coefficient of each unit of the outer flow path of the preposed diffuser
Maximum static pressure recovery coefficient of each unit of intermediate flow path
And maximum quiet per unit of internal flow pathCoefficient of pressure recovery
The design method of the three-channel preposed diffuser divides the difference of effective factors of the inlet and outlet sections of the outer flow path, the middle flow path and the inner flow path of the three-channel preposed diffuser into K O 、K M 、K i The reduction in the effective factor is considered linear along the axial length of the pre-diffuser.
In step nine, calculating the ratio of the outlet cross-sectional area to the inlet cross-sectional area of each unit of the outer flow path, the middle flow path and the inner flow path of the pre-diffuser comprises:
outlet cross-sectional area a of each cell of the outer flow path O(J+1) And the inlet cross-sectional area A O(J) The ratio of (A) to (B) is as follows:
cross-sectional area A of outlet of each cell of intermediate flow path M(J+1) And the inlet cross-sectional area A M(J) The ratio of (A) to (B) is:
outlet cross-sectional area a of each unit of the inner flow path i(J+1) And the inlet cross-sectional area A i(J) The ratio of (A) to (B) is:
after the ratio of the outlet cross-sectional area to the inlet cross-sectional area of each unit of the outer flow path, the middle flow path and the inner flow path of the pre-diffuser is obtained, the calculated area ratio is compared with the assumed area ratio, if the calculated area ratio is equal to the assumed area ratio, the convergence condition calculation is finished, otherwise, the outer flow path area ratio AR is corrected 3O The intermediate flow passage area ratio AR 3M And inner flow passage area ratio AR 3i And starting to calculate from the step five until the convergence condition is met. And finally, determining the sizes of the inner and outer wall flow paths of the diffuser at each section by using a geometrical relationship according to the area of each unit, the central line corner and the inner and outer diameter parameters of the diffuser inlet.
According to the design method of the three-channel front diffuser, the maximum static pressure recovery coefficient of each flow path of the front diffuser is effectively guaranteed by adopting a 'G parameter method', profile parameters of each flow path of the three-channel front diffuser can be quickly formed, and the design of the initial performance scheme of the three-channel front diffuser is completed. Compared with the prior art, the method and the device solve the defect that the existing three-channel front diffuser design method is insufficient, greatly shorten the design period of the three-channel front diffuser scheme, especially accelerate the iteration speed of the demonstration scheme in the demonstration stage of the engine scheme, save a large amount of time and labor cost, and bring higher economic benefits.
The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims (9)
1. A method for designing a three-channel front diffuser is characterized by comprising the following steps:
the method comprises the following steps of firstly, obtaining flow distribution data of a preposed diffuser, and respectively determining the inlet areas and the inlet heights of an outer flow path, a middle flow path and an inner flow path of the preposed diffuser according to the flow distribution data, wherein the method comprises the following steps:
obtaining flow distribution data of a front diffuser, and obtaining mass flow W of the air flow flowing to an outer ring of the front diffuser according to the flow distribution data of the front diffuser O Gas flow mass flow W at the head of the flame tube M And inner ring air flow mass flow rate W i ；
Outer flow path inlet area A of front diffuser 3O The area A of the inlet of the intermediate flow path 3M And the inlet area A of the inner flow path 3i The following relationship exists:
A 3o :A 3M :A 3i ＝W o ：W M ：W i
obtaining:
wherein,
according to the outer flow path inlet area A of the front diffuser 3O The area A of the inlet of the intermediate flow path 3M And the inlet area A of the inner flow path 3i Respectively determining the inlet height H of the outer flow path of the pre-diffuser 3O Intermediate flow path inlet height H 3M And insideHeight H of flow path inlet 3i ；
Selecting parameters of an outer flow path, a middle flow path and an inner flow path of the front diffuser according to the flow distribution data;
dividing an outer flow path, a middle flow path and an inner flow path of the front diffuser into a plurality of units with cross sections perpendicular to the center line along the center line, and calculating the length of each unit;
step four, calculating the outlet effective factors of the outer flow path, the middle flow path and the inner flow path of the front diffuser;
determining area ratio iteration initial values of an outer flow path, a middle flow path and an inner flow path of the front diffuser;
calculating design parameters G of an outer flow path, a middle flow path and an inner flow path of the front diffuser;
step seven, calculating the inlet equivalent effective factors of the outer flow path, the middle flow path and the inner flow path of the front diffuser;
step eight, calculating the maximum static pressure recovery coefficient of each unit of the outer flow path, the middle flow path and the inner flow path of the front diffuser;
step nine, calculating the ratio of the outlet section area to the inlet section area of each unit of the outer flow path, the middle flow path and the inner flow path of the front diffuser, judging whether the ratio meets the requirement, if so, entering the next step, and if not, returning to the step five to re-determine the initial iteration value of the area ratio;
and step ten, determining the sizes of the inner and outer wall flow paths of the outer flow path, the middle flow path and the inner flow path of the front diffuser.
2. The method of designing a three-channel diffuser according to claim 1, wherein in step two, the selecting parameters of an outer flow path, an intermediate flow path and an inner flow path of the diffuser according to the flow distribution data comprises:
selecting according to the flow distribution data:
outer flow path center line corner alpha of front diffuser difO Center line rotation angle alpha of intermediate flow path difM And inner flow path center line angle alpha difi ；
Outer flow path length L of front diffuser preO Intermediate flow path length L preM And inner flow path length L prei ；
Blockage ratio B of outer flow path inlet of front diffuser O Intermediate flow path inlet blockage ratio B M And internal flow path inlet blockage ratio B i 。
3. The method of designing a three-channel front diffuser of claim 2, wherein in step three, the step of dividing the outer flow path, the middle flow path and the inner flow path of the front diffuser into a plurality of units with cross sections perpendicular to the center line along the center line and the step of calculating the length of each unit comprises:
the outer flow path, the middle flow path and the inner flow path of the front diffuser are divided into K along the central line O 、K M 、K i A unit with a section perpendicular to the centre line, the length S of each unit being:
S O ＝L preo /K O
S M ＝L preM /K M
S i ＝L prei /K i 。
wherein, K O 、K M 、K i The value of (A) ensures that the length S of each unit is about 1 mm.
4. The method of designing a three-channel front diffuser of claim 3, wherein in step four, the calculating the outlet efficaciousness factors of the outer, intermediate, and inner flow paths of the front diffuser comprises:
calculating the effective factor E of the outer flow path outlet of the preposed diffuser 2O Intermediate flow path exit effectiveness factor E 2M And inner flow path exit effectivity factor E 2i ：
E 2O ＝1-0.183(L gapo /H 30 ) 0.408 B o 0.315
E 2M ＝1-0.183(L gapM /H 3M ) 0.408 B M 0.315
E 2i ＝1-0.183(L gapi /H 3i ) 0.408 B i 0.315 。
5. The method of designing a three-channel front diffuser of claim 4, wherein in step five, the determining initial iterative area ratio values for the outer flow path, the middle flow path, and the inner flow path of the front diffuser comprises:
determining initial value AR of outer flow path area ratio iteration of pre-diffuser 30 Intermediate flow path area ratio iterative initial value AR 3M And initial value AR of inner flow path area ratio iteration 3i 。
6. The method of designing a three-channel front diffuser of claim 5, wherein in step six, the calculating design parameters G of the outer flow path, the middle flow path and the inner flow path of the front diffuser includes:
calculating the outer flow path design parameter G of the pre-diffuser O Design parameters G of intermediate flow path M And inner flow path design parameters G i *：
G O * ＝E 2O 2 (0.985AR 3O 1.93 -1) -0.5
G M * ＝E 2M 2 (0.985AR 3M 1.93 -1) -0.5
G i * ＝E 2i 2 (0.985AR 3i 1.93 -1) -0.5 。
7. The method of designing a three-channel front diffuser of claim 6, wherein in step seven, calculating the equivalent effective factors of inlets of the outer, middle and inner flow paths of the front diffuser comprises:
calculating the equivalent effective factor E of the outer flow path inlet of the preposed diffuser 1O Intermediate flow path inletEquivalent effective factor E 1M And an equivalent effective factor E of an inlet of the internal flow path 1i ：
When E is 2O 、E 2M 、E 2i >At 0.825 time:
E 1O ＝1-0.0123E 2O -14.025 AR 3O -4
E 1M ＝1-0.0123E 2M -14.025 AR 3M -4
E 1i ＝1-0.0123E 2i -14.025 AR 3i -4
when E is 2O 、E 2M 、E 2i When the content is less than or equal to 0.825:
E 1O ＝1-0.0448E 2O -6.723 AR 3O -4
E 1M ＝1-0.0448E 2M -6.723 AR 3M -4
E 1i ＝1-0.0448E 2i -6.723 AR 3i -4 。
8. the method of designing a three-channel front diffuser of claim 7, wherein in step eight, the calculating the maximum static pressure recovery coefficient of each unit of the outer, middle and inner flow paths of the front diffuser comprises:
calculating the maximum static pressure recovery coefficient of each unit of the outer flow path of the preposed diffuser
Maximum static pressure recovery coefficient of each unit of intermediate flow path
And maximum static pressure recovery coefficient of each unit of the inner flow path
9. The method of designing a three-channel front diffuser of claim 8, wherein in the ninth step, the calculating the ratio of the outlet cross-sectional area to the inlet cross-sectional area of each cell of the outer, intermediate, and inner flow paths of the front diffuser comprises:
outlet cross-sectional area a of each cell of the outer flow path O(J+1) And the inlet cross-sectional area A O(J) The ratio of (A) to (B) is:
cross-sectional area A of outlet of each cell of intermediate flow path M(J+1) And inlet cross-sectional area A M(J) The ratio of (A) to (B) is:
outlet cross-sectional area a of each unit of the inner flow path i(J+1) And the inlet cross-sectional area A i(J) The ratio of (A) to (B) is:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111369477.3A CN114021262B (en) | 2021-11-15 | 2021-11-15 | Design method of three-channel front diffuser |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111369477.3A CN114021262B (en) | 2021-11-15 | 2021-11-15 | Design method of three-channel front diffuser |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114021262A CN114021262A (en) | 2022-02-08 |
| CN114021262B true CN114021262B (en) | 2022-09-20 |
Family
ID=80065053
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111369477.3A Active CN114021262B (en) | 2021-11-15 | 2021-11-15 | Design method of three-channel front diffuser |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114021262B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013105259A (en) * | 2011-11-11 | 2013-05-30 | Toyo Tire & Rubber Co Ltd | Device for designing cross-sectional shape of channel, and method and program therefor |
| CN104595033A (en) * | 2015-02-12 | 2015-05-06 | 厦门大学 | Design method of pre-posed diffuser controlled based on total pressure loss |
| CN108052694A (en) * | 2017-11-15 | 2018-05-18 | 中国航发沈阳发动机研究所 | Stealth after-burner inner cone design method |
| CN110100084A (en) * | 2016-10-21 | 2019-08-06 | 康明斯有限公司 | The method for designing turbine |
| JP2021084235A (en) * | 2019-11-25 | 2021-06-03 | 日立金属株式会社 | Flow channel structure determination method, mold, flow channel structure determination device, flow channel structure determination program, and recording medium |
-
2021
- 2021-11-15 CN CN202111369477.3A patent/CN114021262B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013105259A (en) * | 2011-11-11 | 2013-05-30 | Toyo Tire & Rubber Co Ltd | Device for designing cross-sectional shape of channel, and method and program therefor |
| CN104595033A (en) * | 2015-02-12 | 2015-05-06 | 厦门大学 | Design method of pre-posed diffuser controlled based on total pressure loss |
| CN110100084A (en) * | 2016-10-21 | 2019-08-06 | 康明斯有限公司 | The method for designing turbine |
| CN108052694A (en) * | 2017-11-15 | 2018-05-18 | 中国航发沈阳发动机研究所 | Stealth after-burner inner cone design method |
| JP2021084235A (en) * | 2019-11-25 | 2021-06-03 | 日立金属株式会社 | Flow channel structure determination method, mold, flow channel structure determination device, flow channel structure determination program, and recording medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114021262A (en) | 2022-02-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110059414B (en) | Two-dimensional blade modeling method for directly controlling channel | |
| CN109927917B (en) | Integrated design method for internal rotation type wave-rider forebody air inlet channel of supersonic aircraft | |
| CN109140732B (en) | Energy-saving current-sharing targeted air supply outlet | |
| CN114021262B (en) | Design method of three-channel front diffuser | |
| CN106949095B (en) | The optimization method of Low-pressure axial fan impeller blade | |
| CN106446324A (en) | Design method for last-stage torsional blade of large industrial steam turbine | |
| CN104200012B (en) | Expand the method for steady ability for comparing treated casing scheme | |
| CN109737095B (en) | Bionic centrifugal pump blade | |
| CN113153773B (en) | Bionic multi-wing centrifugal fan impeller and preparation method thereof | |
| CN103174520A (en) | Subsonic outflowing high external pressure internal waverider type air inlet and designing method thereof | |
| CN116992601B (en) | Design method of volute runner | |
| CN109611211B (en) | Aero-engine inner cone cooling design method | |
| JP2017500486A (en) | Blade for turbomachine impeller and how to model this blade | |
| CN201301753Y (en) | Inner wave rider type air inlet channel taking internal and external flow performance into consideration | |
| CN112197296A (en) | Flame tube wall plate | |
| CN205639070U (en) | Blade suction surface has broken structure in whirlpool and grooved axial fan in leaf top | |
| CN114542216B (en) | Turbine support plate blade design method with supporting and guiding functions and blade | |
| CN113361027B (en) | Design method of hidden afterburner flow guide support plate | |
| CN112733268A (en) | Asymmetric trapezoid-like spray pipe throat design method | |
| CN115659527A (en) | Gas film cooling hole outlet hole pattern design method based on multi-segment spline curve | |
| CN114564817A (en) | Design method for torque-shaped outlet isolation section of fan annular inlet | |
| CN107013490A (en) | A kind of optimization method of Low-pressure axial fan impeller blade | |
| CN114046538A (en) | Turbulent flow type efficient flame tube cooling structure | |
| CN206130984U (en) | Fire cover for gas kitchen range | |
| CN110454961A (en) | It is a kind of to disappear the uneven annular water conservancy diversion orifice fitting in whirlpool for jet stream restricted clearance |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |