涡轮机械系统参数化三维叶片几何建模工具优质PPT.pptx

1、,Parametric 3D Blade Geometry Modeling Toolfor Turbomachinery Systems,Kiran Siddappaji 05/10/2012School of Aerospace SystemsCommittee Chair:#Dr.Mark G.TurnerCommittee:#Dr.Paul D.Orkwis Dr.Shaaban Abdallah,Overview,Motivation3DBGBProcess FlowchartInput Parameterization3D Blade GeneratorGoverning Equa

2、tionsBlade section constructionStreamwise mapping of blade sectionsSweep and LeanRadial stacking of 3D blade sectionsCoordinate transformation3D blade lofting and CAD connectionExample casesConclusion and Future WorkFlexibility Demonstration,Motivation,Blade design defines component performance.Iter

3、ative,hence requires quicker and robust process.A parametric approach is desired.Design tool with limited CAD interaction.Design Flexibility and Generality are desired with minimal input modifications.Must be applicable to large design space.,Option to be part of any automation and optimization chai

4、n.,The GENX Engine.1,3DBGB,3DBGB（3 Dimensional Blade Geometry Builder）is a parametric blade design tool.3D blade sections are created using conformal mapping.Blade sections can be radially stacked at any specified location to obtain a 3D blade model.Parametric spline update makes the geometry modifi

5、cation process quicker.Limited CAD interaction to obtain newer blade shapes.,Process Flowchart,Input Parameterization,Relative flow angles at leading edge and trailing edge of the blade.Thickness to chord ratio,Axial chord values.Relative inlet mach number.Incidence,Deviation and Secondary flow angl

6、es.Leading and Trailing Edge curves（x,r）.Control points defining lean and sweep perturbations and any other quantity.Stacking option.Streamline coordinates from an axisymmetric run like T-Axi 2 or smooth construction curves.,10 stage HPC rotor 1,10 stage HPC rotor 3,TIP VIEW,HUB VIEW,TIP VIEW,HUB VI

7、EW,Governing Equations,:#,Blade Section Construction,Rotor 1 of 10 stage HPC,Non-dimensional chordwise coordinate:#uNon-dimensional coordinate perpendicular to u:#v,Inputs:#,Blade metal anglesThickness to chord ratioMeridional chord,*in*,out,=Blade metal angle at Leading Edge=Blade metal angle at Tr

8、ailing Edge,=Relative flow angle at Leading Edge,inout=Relative flow angle at Trailing Edge=Stagger Angle,i=Incidence Angle,ininin,=-*when*0,in,=*-when*0,inin=Deviation Angle,=*-（camber 0）outout=out-*（camber 0）out,Camber line Definition and Plots,Camber Line plot,Camber Angle plot,Curvature plot,Rot

9、or 1 of 10 stage HPC,Staggered and scaled airfoil coordinates,Array ub consists of ubbot and ubtop.Array vb consists of vbbot and vbtop.The values are stored in a counter clockwise manner starting from the trailing edge.Non dimensional leading edge is（0,0）.Non dimensional trailing edge is（1,0）for co

10、nvenience.Also,thk is the thickness definition given by Wennerstrom 3.,（Coordinate Rotation）,（Coordinate Scaling）,（meridional chord）,（actual chord）,Wennerstrom thickness definition3,Coefficients a through h can be obtained with proper boundary conditions.An elliptical Leading Edge and a circular Tra

11、iling edge is used.Elliptical leading edge keeps the flow attached and laminar 4.,Variety of airfoils,Capability of generating different airfoil shapes and highly staggered airfoils.Currently capable of NACA 4 digit,S809,circular and mixed camber（default）.,Leading and Trailing Edge curves,Defined by

12、 2D cubic spline curves in x,r.Cubic spline is used to fit the streamline coordinates xs,rs with ms as the spline parameter.Intersection of the above 2 spline curves produces xLE,rLE and xTE,rTE on each corresponding streamline（construction curve）.Using these points,msLE-the leading edge ms value is

13、 calculated which is crucial in streamwise mapping of the blade sections as explained in the next section.,Streamwise Mapping of the Blade Sections,meridional offset:#,Meridional offset is necessary for precise conformation of the blade section on its corresponding streamline.This is because the zer

14、o ms on each streamline is different from the mbLE on each corresponding blade section.,msLE=ms value evaluated at xLE on a streamline.mbLE=mb value at the LE of the airfoil.,Similarly,Streamwise Coordinate Calculation,x3D,r3D and 3D coordinates are thus calculated.,Mapping of the Blade Sections,Map

15、ping of the blade section on the corresponding stream surface.,Sweep,Spanwise Sweep Perturbation,Perturbations are defined spanwise using few control points for a cubic B-spline curve.,Cubic B-spline construction,5,A simple intersection procedure of 2D curve and a line gives the desired point on the

16、 smooth spline curve.,Lean,Spanwise Lean Perturbation,Perturbations are defined spanwise using few control points for a cubic B-spline curve.,Overview,Motivation3DBGBProcess FlowchartInput Parameterization3D Blade GeneratorGoverning EquationsBlade section ConstructionStreamwise Mapping of blade sectionsSweep and LeanRadial Stacking of 3D blade sectionsCoordinate Transformation3D blade lofting and CAD connectionExample CasesConclusion and Future WorkFlexibility Demonstration,Radial stacking of 3D airfoi