OpenVSP Workshop (6) Rob McDonald. Cliffs Resort, Pismo Beach CA August 30 Sept 1, 2017

Transcription

1 OpenVSP Workshop (6) Rob McDonald Cliffs Resort, Pismo Beach CA August 30 Sept 1,

2 Geometry as Origin of Analysis (Design) Shape is fundamental starting point for physics-based analysis Aerodynamics Structures Aeroelasticity Aerothermal / Heating Mass Properties Acoustics RCS / Signatures Packaging / Layout Manufacturing etc. Across disciplines and fidelity, shape is the common denominator. Unfortunately, there is little to no commonality in practice. 2

3 Geometry (Mis)Representation True geometry does not correspond to analysis representation. CAD models can be built with varying (single) intent Manufacturing Represent manufacturing process, target CAM Integration & Maintenance Packaging, accessibility, etc. Structures Represent loads & load paths, target FEA Many elements do not correspond to CAD model Beam, rod, shell, plate, etc. Aerodynamics Represent OML, propulsion, control surfaces 3

4 Geometry Modeling Gap Three approaches have evolved to geometry modeling for physics-based analysis. Analysis Integrated Each code generates geometry based on its own inputs. OpenVSP CAD Based General-purpose CAD is used to model geometry. Prepared for analysis through grid generation and pre-processing tools. 4

5 Analysis Fidelity Holes Single model-to-analysis work flow typically developed. Fidelity selected (at least limited) by geometry model. Very little choice in analysis fidelity. Sparsely populated fidelity / discipline matrix. 5

6 Many Models Possible Representation of Geometry Shape Concept and Parameters are Geometry AR, S, Λ, λ, t/c 6

7 Representation Relates to Fidelity Vortex Lattice Panel Code CFD 7

8 Often Mistaken for Design Stage Vortex Lattice Panel Code CFD Conceptual Preliminary Detail 8

9 Phases of Aircraft Design Design phase is about what decisions are being made, not how they are made.* Phase I Conceptual Design Phase II Preliminary Design Vs. Phase III Detail Design Vs. Vs. 3 O 5 O Known Basic Mission Requirements Range, Altitude, Speed Basic Material Properties s/r E/r $.lb Aeroelastic Requirements Fatigue Requirements Flutter Requirements Overall Strength Requirements Local Strength Requirements Producibility Functional Requirements Results Geometry Air Foil Type R t/c l D Design Objectives Drag Level Weight Goals Cost Goals Basic Internal Arrangement Complete External Configuration - Camber, Twist Distributions - Local Flow Problems Solved Major Loads, Stresses, Deflections Detail Design - Mechanisms - Joints, Fittings & Attachments Design Refinements as Results of Test Output Feasible Design Mature Design Shop Drawings TRL Leland Nicolai, Fundamentals of Aircraft and Airship Design, AIAA, *Except where certain decisions require more advanced techniques. 9

10 Parameters Evolve Through Design Shape Concept and Parameters are Geometry Conceptual True through entire design process. Preliminary Detail AR, S, Λ, λ, t/c General Concept twist = f(η), t/c = f(η), Complex Planform, High-lift geometry, Control surfaces High-Level Finesse Detailed part designs Every Aspect Determined Design phase is about what decisions are being made, not how they are made. 10

11 OpenVSP Evolution Workshop 2012 Inaugural v Langley 2016 Ames 2017 Version (2.9.4) How many workshops have you been to? Are you using years old software? 11

12 Features Since Blended wings Conformal components Parasite drag buildup tool SubSurface areas in CompGeom Ellipsoid and Body of Revolution geometry von Karman Trefftz airfoil type Complete VSPAERO integration VSPAERO 3.1, 4.1, (Unsteady, ground effect, faster, etc) DegenGeom preview Advanced control surface modeling Spin control for Fuse and Stack New clustering function Optimized CFDMesh, FitModel, Prop, Wing, Fuse, CompGeom Optionally omit blunt TE from STEP/IGES Split IGES/STEP along U/W-Const SubSurface lines Mesh STL files optionally write surfaces or slices XPatch export SVG 2D Export Outlines in 2D Export Countless Bug Fixes 12

13 Agenda Wednesday 8/30/2017 Thursday 8/31/2017 Friday 9/1/2017 8:00 8:30 Welcome & Overview Rob McDonald VSPAERO Overview Nick Brake OpenMDAO / ModelCenter Plugin Jason Welstead 8:30 9:00 Introduction to OpenVSP Brandon Litherland VSPAERO GUI VLM Basics Nick Brake Using OpenVSP and VSPAERO with the OpenMDAO Environment Mark L. McMillin 9:00 9:30 Basic Modeling Brandon Litherland VSPAERO Verification Testing Lucas Payne OpenVSP in the NAVAIR Fixed Wing Conceptual Design Tool AJ Field 9:30 10:00 Tour of main components Brandon Litherland VSPAERO GUI Advanced Nick Brake NDARC Integration Update Travis Perry 10:00 10:30 Break Break Break 10:30 11:00 XSecs in detail Brandon Litherland Structures Overview Justin Gravett 11:00 11:30 UIUC STTR Update Jeff Freeman Structures Demo Justin Gravett Physics-Based Weight (PBWeight) Prediction for Conceptual Design Tyler Winter 11:30 12:00 USAF/NASA SBIR Wrapup Nick/Ben Structures Tutorial Justin Gravett 12:00 12:30 12:30 13:00 Lunch Lunch Lunch 13:00 13:30 Attach, hinges, symmetry, sets, subsurfaces Rob McDonald Propeller Folding and Fillet Construction Brandon Litherland Transonic and Viscous Corrections to VSPAERO Daniel Chapparo 13:30 14:00 Skinning explained Rob McDonald Advanced Parameter Linking Rob McDonald Parasite Drag Buildup Bryan Schmidt 14:00 14:30 Conformal Components Rob McDonald Design Vars, XDDM, API, Scripting Rob McDonald 14:30 15:00 Break Break Workshop End 15:00 15:30 Parametric Weight Analysis using OpenVSP Erik Olsen Advanced Wing Modeling Rob McDonald 15:30 16:00 Roy Hartfield VSP CAD to Aero Loads with FlightStream 16:00 16:30 Roy Hartfield Modeling Demo Rob McDonald 16:30 17:00 Feedback Session Rob McDonald 17:00 17:30 17:30 18:00 18:00 18:30 BBQ social 13

14 Questions? 14