Development of a Blade Parametric Modeling Methodology for Design and Analysis of Computer Experiments

2015 ◽  
Author(s):  
Zafer Leylek ◽  
A. J. Neely
Keyword(s):  
Physical Space ◽  
Computer Experiments ◽  
Parametric Modeling ◽  
Rotor Blades ◽  
Geometric Feature ◽  
Physical Parameters ◽  
Base Line ◽  
Turbine Stator ◽  
Modeling Methodology ◽  
Feature Based

This paper will present an enhanced parametric modeling technique for gas turbine stator and rotor blades. The enhanced blade parametric modeling system has been developed as part of a wider research program into global surrogate modeling of compressor and turbine aerodynamic performance using Design and Analysis of Computer Experiments (DACE) based techniques. The proposed method is based on a hybrid of geometric feature and Non-uniform Rational B-Spline (NURBS) based techniques. A base-line geometry is defined using the physical parameters and represented using NURBS curves and surfaces. A number of constraints are then imposed on the parametric model to ensure that DACE techniques can be effectively utilized. This is accomplished by mapping the geometric feature based parameters from the physical space to an alternative parametric space so that all feasible and numerically stable blade configurations can be represented using a unit hyper-cube. This method ensures a one-to-one mapping between the parametric sub-space and the geometric feature based system. The mapping is geometrically and numerically stable and does not produce ill-conditioned and unrealistic blade geometries. The development of the blade parametric modeling process allows the application of the complete suit of DACE tools and techniques. The method is valid for all axial blade profiles which include compressor and turbine stator and rotor blades.

CAD Training Using Interactive Computer Sessions Emphasizing Design Intent

1998 ◽  
Author(s):  
Jorge Rodriguez ◽  
James Ridge ◽  
Amy Dickinson
Keyword(s):  
Parametric Modeling ◽  
Design Stage ◽  
Solid Model ◽  
Design Intent ◽  
Variational Design ◽  
Modeling Methodology ◽  
Modeling Process ◽  
Dimensional Parameters ◽  
Feature Based ◽  
Beta Testing

Abstract This project addresses the need to train CAD users on proper modeling methodology. New CAD software empowers designers with the flexibility of parametric or variational design. These feature-based parametric modeling packages allow modification of a solid model by changing its dimensional parameters; however, incorrect modeling methodology may cause failure in the design stage. Failures occur when modified dimensions cause a conflict within the geometry of the model. An option being used is to train designers on capturing the Design Intent of a system through proven techniques in the modeling process. This training is based on interactive computer sessions that guide the designer and allow him/her to explore what-if scenarios. This project sought to identify proven techniques in the modeling process for capturing the Design Intent of mechanical systems. The familiar components of a bicycle provided a basis for exploration. Pro/Enginner™ software was used in this study. Nine lessons were created and tested by professionals. Beta testing was conducted at Steelcase-Chair Division with positive feedback from novice and advanced CAD users.

Circulation Control Span-Wise Blowing Location Optimization for a Helicopter Rotor Blade

2010 ◽  
Author(s):  
Alan M. Didion ◽  
Jonathan Kweder ◽  
Mary Ann Clarke ◽  
James E. Smith
Keyword(s):  
Stress Reduction ◽  
Rotor Blades ◽  
Helicopter Rotor ◽  
Base Line ◽  
Control Technology ◽  
Circulation Control ◽  
High Lift ◽  
Location Optimization ◽  
Helicopter Rotor Blades ◽  
Length Reduction

Circulation control technology has proven itself useful in the area of short take-off and landing (STOL) fixed wing aircraft by decreasing landing and takeoff distances, increasing maneuverability and lift at lower speeds. The application of circulation control technology to vertical take-off and landing (VTOL) rotorcraft could also prove quite beneficial. Successful adaptation to helicopter rotor blades is currently believed to yield benefits such as increased lift, increased payload capacity, increased maneuverability, reduction in rotor diameter and a reduction in noise. Above all, the addition of circulation control to rotorcraft as controlled by an on-board computer could provide the helicopter with pitch control as well as compensate for asymmetrical lift profiles from forward flight without need for a swashplate. There are an infinite number of blowing slot configurations, each with separate benefits and drawbacks. This study has identified three specific types of these configurations. The high lift configuration would be beneficial in instances where such power is needed for crew and cargo, little stress reduction is offered over the base line configuration. The stress reduction configuration on the other hand, however, offers little extra lift but much in the way of increased rotor lifespan and shorter rotor length. Finally, the middle balanced configuration offers a middle ground between the two extremes. With this configuration, the helicopter benefits in all categories of lift, stress reduction and blade length reduction.

Automatic Parametric Modeling From Non-Feature Based Designs for Additive Manufacturing

2021 ◽  
Author(s):  
Xinyi Xiao ◽  
Byeong-Min Roh
Keyword(s):  
Additive Manufacturing ◽  
3D Models ◽  
Parametric Modeling ◽  
Parametric Models ◽  
Performance Simulation ◽  
Cad Modeling ◽  
3D Cad ◽  
Feature Based ◽  
And Performance ◽  
The Given

Abstract The integration of Topology optimization (TO) and Generative Design (GD) with additive manufacturing (AM) is becoming advent methods to lightweight parts while maintaining performance under the same loading conditions. However, these models from TO or GD are not in a form that they can be easily edited in a 3D CAD modeling system. These geometries are generally in a form with no surface/plane information, thus having non-editable features. Direct fabricate these non-feature-based designs and their inherent characteristics would lead to non-desired part qualities in terms of shape, GD&T, and mechanical properties. Current commercial software always requires a significant amount of manual work by experienced CAD users to generate a feature-based CAD model from non-feature-based designs for AM and performance simulation. This paper presents fully automated shaping algorithms for building parametric feature-based 3D models from non-feature-based designs for AM. Starting from automatically decomposing the given geometry into “formable” volumes, which is defined as a sweeping feature in the CAD modeling system, each decomposed volume will be described with 2D profiles and sweeping directions for modeling. The Boolean of modeled components will be the final parametric shape. The volumetric difference between the final parametric form and the original geometry is also provided to prove the effectiveness and efficiency of this automatic shaping methodology. Besides, the performance of the parametric models is being simulated to testify the functionality.

Symplectic calculation of the outboard magnetic footprint from noise and error fields in the DIII-D

2011 ◽  
Vol 77 (6) ◽  
pp. 785-802
Author(s):  
HALIMA ALI ◽  
ALKESH PUNJABI ◽  
ERNEST NYAKU
Keyword(s):  
Magnetic Field ◽  
Field Line ◽  
Generating Function ◽  
Magnetic Field Line ◽  
Physical Space ◽  
Physical Parameters ◽  
Canonical Coordinates ◽  
Step Size ◽  
Magnetic Perturbation ◽  
Collector Plate

AbstractThe backward symplectic DIII-D map and continuous symplectic analog of the map for magnetic field line trajectories in the DIII-D [10] (Luxon, J. L. and Davis, L. E. 1985 Fusion Technol.8, 441) in natural canonical coordinates are used to calculate the magnetic footprint on the outboard collector plate of the DIII-D tokamak from the field errors and internal topological noise. The equilibrium generating function for the DIII-D used in the map very accurately represents the magnetic geometry of the DIII-D. The step-size of the map is kept considerably small so that the magnetic perturbation added from symplectic discretization of the Hamiltonian equations of the magnetic field line trajectories is very small. The natural canonical coordinates allow inverting to the real physical space. The combination of highly accurate equilibrium generating function, natural canonical coordinates, symplecticity, and small step-size then together gives a very accurate calculation of magnetic footprint. Radial variation of magnetic perturbation and the response of plasma to perturbation are not included. The footprint is in the form of toroidally winding helical strips. The area of footprint scales as 1st power of amplitude. The physical parameters as toroidal angle, length, and poloidal angle covered before striking, and the safety factor all have fractal structure. The average field diffusion near X-point for lines that strike and that do not strike differs by about four orders of magnitude. The flux loss decreases for high values of amplitude of perturbation.

Comparison of Steady and Unsteady Secondary Flows in a Turbine Stator Cascade

1989 ◽  
Author(s):  
Gregory J. Hebert ◽  
William G. Tiederman
Keyword(s):  
Secondary Flows ◽  
Rotor Blades ◽  
Velocity Measurements ◽  
Flow Loop ◽  
Suction Surface ◽  
Linear Cascade ◽  
Turbine Stator ◽  
Passage Vortex ◽  
Blade Row ◽  
Secondary Flow Structure

The effect of periodic rotor wakes on the secondary flow structure in a turbine stator cascade was investigated. A mechanism simulated the wakes shed from rotor blades bypassing cylindrical rods across the inlet to a linear cascade installed in a recirculating water flow loop. Velocity measurements showed a passage vortex, similar to that seen in steady flow, during the time associated with undisturbed fluid. However, as the rotor wake passed through the blade row, a large crossflow toward the suction surface was observed in the midspan region. This caused the development of two large areas of circulation between the midspan and endwall regions, significantly distorting and weakening the passage vortices.

Inverse Parametric Modeling From Independently Generated Product Data Sets

2002 ◽  
Author(s):  
Zhengdong Huang ◽  
Derek Yip-Hoi
Keyword(s):  
Product Family ◽  
Parametric Model ◽  
Parametric Modeling ◽  
Data Sets ◽  
Data Set ◽  
Product Families ◽  
Part Family ◽  
Product Data ◽  
Feature Based ◽  
Parameter Ranges

Parametric modeling has become a widely accepted mechanism for generating data set variants for product families. These data sets that include geometric models and feature-based process plans are created by specifying values for parameters within feasible ranges specified as constraints in the definition. The ranges denote the extent or envelope of the product family. Increasingly, with globalization the inverse problem is becoming important. This takes independently generated product data sets that on observation belong to the same product family and creates a parametric model for that family. This problem is also of relevance to large companies where independent design teams may work on product variants without much collaboration only to attempt consolidation later on to optimize the design of manufacturing processes and systems. In this paper we present a methodology for generating a feature-based part family parametric model through merging independently generated product data sets. We assume that these data sets are feature-based with relationships such as precedences captured using graphs. Since there are typically numerous ways in which these data sets can be merged, we formulate this as an optimization problem and solve using the A* algorithm. The parameter ranges generated by this approach will be used to design appropriate Reconfigurable Machine Tools (RMTs) and systems (RMS) for manufacturing the resulting part family.

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