Navy Ship

Advanced

Modeling

&

Simulatio

n -

NSRP

Projects

Navy Ship

Advanced

Modeling

&

Simulatio

n -

NSRP

Projects

The Are Two Current NSRP Modeling & Simulation Projects

1.) NSRP RA 06-01:

Improved Methods for Generation of Full-Ship Simulation/Analysis Models

2.) Panel Project:

Ship STEP AP Application to Full-Ship Analysis Model Generation

This Project

NSRP RA 06-01: Improved Methods for Generation of Full-Ship Simulation/Analysis Models

Description: This project is aimed at reducing the cycle time required to develop large scale full ship analysis models for strength, stress, shock, and acoustic simulation and assessment. It responds to Navy Program Executive Officer (PEO) interest in expanding use of modeling and simulation to reduce costs associated with current methods of ship structural testing and analysis. The team will build on the VIRGINIA program’s success in substituting analysis for at-sea live-fire tests, considerable NSRP prior work in design data interoperability, and prior industry investments in ship design tools. The project team will engage with the Navy Full Ship Shock Trial Integrated Process Team (FSST-IPT) to examine cost effective alternatives to replace open-ocean, large-scale shock trials of surface ships.

Participants: General Dynamics Electric Boat, Northrop Grumman Ship Systems, Others (TBD)

The Other Project

Lead: General Dynamics – Electric Boat Corporation (EBC)

Subcontractors:

Northrop Grumman – Ship Systems (NGSS) American Bureau of Shipping (ABS)Product Data Services (PDS)Intergraph Corporation (IC)

PDS, Inc.

This NSRP Panel Project

Ship STEP AP Application to Full-Ship Analysis Model

Generation

Overall Background to Both NSRP Modeling & Simulation

Projects

FSST-IPT

Full-Ship Live-Fire Shock Testing can be Prohibitively Expensive!

• Computational Mechanics Transient Simulation is one Viable Alternative • Has Recently Been Accredited for Virginia Class Submarines by PMS450

• (PEOSUB letter 13031 Ser 450/0295 dated 28 Jun 06)

The Design of Naval Vessels Involves Various High-End Computational

Mechanics and Simulation Needs.

But Its Not Just Shock!

Acoustics

Hydrodynamics

Critical Areas in Ultra-Large Container Carriers

Commercial Ships Also Have Full-Ship Analysis Requirements

De-Feature, Heal, Mid-Surface

Common Abstract Analysis Model

CAD 3D Design

StressAnalysis

ShockAnalysis

AcousticAnalysis

AnalysisContext

AnalysisContext

Related Modeling & Simulation Efforts

We Have Needs for Multi-Disciplinary Modeling &

Simulation (M&S) Environments Which Support

Varied Requirements

AnalysisContext

We Need to Consider Multiple Design Stages or Phases (Concept, Preliminary, Detailed, …)

Examples of CAD System Usage

We Need to be More Nimble and Agile in order to Support Various Programs and

Ship Systems (Classes)

DS / CATIA V4 MEC Virginia ClassDS / CATIA V4 AEC CVNX (w/ NNS)DS / CATIA V5 DDG1000 (w/ BIW) AutoCAD SS(G)NPTC / CADDS5 Astute (w/ BAE Vickers)

DS / CATIA V5 DDG1000 (w/ BIW) PTC / Dimension III DDG51ShipConstructor USCG DeepwaterIntergraph / ISDP LPD17

We believe an Open, Standards-Based Framework with “Plug & Play” Capability is Required for Efficient Teaming

EB

NGSS

Overall M&S Background

• Need to significantly reduce cost and time for ship modeling, analysis, and simulation

• Need to address:– Engineering Labor (Navy spends $5B-$7B per year in all

aspects of ship design and engineering).– Live Fire Test and Evaluation (expensive, risky, time

consuming, environmental approvals increasingly difficult to obtain)

Limitations of Current Modeling and Simulation Processes

Designs Developed in

CAD environment• 3-D Product models

• Surface Models• 2-D Drawings

Finite Element Model• Models built using Shell and

Beam Elements• Correct Mass Distribution

Required for Dynamic Analysis

Analysis• Seaway Loads• Weapons Effects

Analysis Modeling Space• Generate Analysis Model

Geometry from Design Information

80% of Time

20% of Time

Too Late to Influence

• Simulation models at this scale are generally not automatically created or readily meshed from CAD geometry.

• Significant “Touch Labor” is usually required.

Full Ship Simulation

SFG

NAVY Ships are a NAVY Ships are a Highly Complex ProductHighly Complex Product

BOEING 777BOEING 777

50,000 HRS50,000 HRS103,000 PARTS103,000 PARTS254 TONS254 TONS

AUTOMOBILESAUTOMOBILES

23 HRS23 HRS3,000 PARTS3,000 PARTS1.9 TONS1.9 TONS

INCREASING INCREASING COMPLEXITYCOMPLEXITY

MANUFACTURING TIME (MONTHS)MANUFACTURING TIME (MONTHS)

MISSILEMISSILE

1,700 HRS1,700 HRS5,000 PARTS5,000 PARTS1.6 TONS1.6 TONS

LAND VEHICLELAND VEHICLE

5,500 HRS5,500 HRS14,000 PARTS14,000 PARTS65 TONS65 TONS

FIGHTER FIGHTER AIRCRAFTAIRCRAFT

57,000 HRS57,000 HRS30,000 PARTS30,000 PARTS10 TONS10 TONS

SSBNSSBN

12,000,000 HRS12,000,000 HRS1,000,000 PARTS1,000,000 PARTS18,750 TONS18,750 TONS

Labor Hours WeightParts

SSNSSN

8,000,000 HRS8,000,000 HRS950,000 PARTS950,000 PARTS6,900 TONS6,900 TONS

0 10 20 30 40 50 60 70 80

15

* Ref.: "The VIRGINIA Class Submarine Program: A Case Study", General Dynamics Electric Boat, February 2002.

Lead: General Dynamics – Electric Boat Corporation (EBC)

Subcontractors:

Northrop Grumman – Ship Systems (NGSS) American Bureau of Shipping (ABS)Product Data Services (PDS)Intergraph Corporation (IC)

PDS, Inc.

This NSRP Panel Project

Ship STEP AP Application to Full-Ship Analysis Model

Generation

Panel Project Approach and Objectives

Task 1: Define Expanded Use of CAD/CAE Surface Model RepresentationsDemonstrate how the expanded use of simpler surface model representations for Naval vessels (submarines and surface ships) will facilitate the creation of full-ship analysis models, and investigate the dual, concurrent capture of such data, in association with (and updated according to) the evolving more detailed CAD solid product model.

Task 2: Address Completeness, Adequacy and Utility of STEP Ship APsAddress the completeness and adequacy of the Ship APs (AP216 and AP218) for content sufficient to build full-ship (submarine and surface ship) FEA models. If gaps are found, identify appropriate extensions to these ship APs. AP218 for ship structures is currently skewed for surface ship semantics. AP218's adequacy and applicability for submarine structures will be investigated.

Task 3: Develop and Publish Integrated Plan and RecommendationsDevelop and publish an integrated plan for follow-on phases (potentially with multiple funding sources) to create a more-automated capability or system for rapid generation of FEA full-ship models and a functional description of a more automated Modeling and Simulation environment. Required extensions to ship APs will be identified and reported.

NSRP Panel Project - Ship STEP AP Application to Full Ship Analysis Model

Generation

During Early Concept Design Stages Various CAE-Centric Codes are Employed

Significant Amounts of Information are Actually Available Early in the Process

Implicit (Parametric) Design Information can be Captured and Made More Persistent Throughout Later Design Stages to

Foster Simulation Model Creation

Toy Illustrations of Early Sub Geometry Concepts

Captured as Major Surface Geometry

Assess how the expanded and persistent use of simpler surface model representations for Naval vessels (both surface ships and submarines) will facilitate the creation of full-ship analysis models.

NSRP Panel Project

AP218: Ship Structures

Structural System Tank Structure

AP218 semantics have a decided surface ship flavor.Does AP218 apply equally well for submarine structures?

AP218 Implicit Geometry is Advantageous

Parts and Features have Parametric Definitions

T Bar Cross Section Drain Hole Cutout

Bulbflat Cross Section

Outward Round Corner Cutout

AP218 Files are Verbose

Will they scale for full-ship scenarios?

Approach and Scope:

• More efficient methods for creation of analysis and simulation models are needed.

• Analysis and simulation has a role across all design phases (or possibly all lifecycle stages); the earlier the better for concurrent engineering.

• Both CAE-Centric and CAD-Centric approaches are necessary for analysis model creation, depending on the scale, scope and purpose of the simulation or analysis, as well as the design phase.

• More persistent use of attributed surface geometry has advantages for creating shell analysis models.

• AP218 may have particular benefit – need to examine and define.

NSRP Panel Project – Details

Approach and Scope (Cont’d.):

• The NSRP ASE/ISE paradigm (use of both or either P21 and/or P28) is accepted (at least by this group).

• Well-ordered sequences of events exist and apply in shipbuilding design evolution from concept formulation to preliminary design to detailed design.

• The shipbuilding ISO STEP Application Protocols for data exchange mirror this orderly progression (at least as it pertains to ship structure) AP215-AP216-AP218.

• AP218 would appear to have adequate ship structure information necessary for the creation of structural ship shell analysis models.

Approach and Scope (Cont’d.):

• Can or does AP218 apply equally well for submarine structural models?

• Are there any things missing (gaps) in AP218 for use with submarines? If so, we will define and describe them.

• Do the AP216 and AP218 data models scale appropriately to a full ship? Are there issues - verboseness, duplicity, etc.?

• Is AP218 too focused on manufacturing? (Four or five of the nine current Conformance Classes for exchange are so defined.)

• The implicit (parametric) geometry definitions in AP218 are desirable. If anything, they do not go far enough.

Approach and Scope (Cont’d.):

• Explicit geometry definitions are generally adequate for CAD-CAE data exchange, being snapshots at points in time or in design stages.

• Explicit geometry can be created on-the-fly when needed; e.g. solids-on-demand of the older NNS wsVIVID tool, Intergraph's ISDP & IntelliShip codes, or that briefly demonstrated at the ISE-4 Final Demonstration (4/06).

• Is the AP218 data model complete enough to form the basis of a persistent CAD-CAE ship structural geometry repository?

• Or should AP218 be relegated to its current status as a simple data exchange mechanism?

Benefits Reduced cost, faster development of

models for simulations of ships and Naval vessels

New approaches may present advantages over traditional forms of finite element model generation employing CAD systems & FEA tools

Reduced M&S cost by employing simpler attributed surface models (throughout the various design process stages)

Leverages recent interoperability initiatives (ISE)

Backup Slides

GoalAssess how the expanded use of simpler surface model representations for Naval vessels (both surface ships and submarines) will facilitate the creation of full-ship analysis models.

NSRP Panel Project

ScopeDevelop and publish an integrated plan to create a more-automated capability or system for rapid generation of FEA full-ship models. Work is underway in other areas to automate ship mesh generation. The purpose of this plan would be to integrate these activities and allow and accommodate the use of the ship APs, and to unify the approach for both surface ships and submarines.

Nominal CADGeometry

Idealized SimulationGeometry

AnalysisModel (FEM)

We Need More Balance in Analysis Model Creation (e.g. FEA)

Geometry is not always the same!

A mechanical engineer, a structural engineer, and a piping engineer may each require different forms of geometry capture.

Both CAD-Centric and CAE-Centric processes are needed.

CAD-Centric CAE-Centric

Nominal CADGeometry

Idealized SimulationGeometry

AnalysisModel (FEM)

SimplifyIdealizeDe-Feature

PaveMeshDiscretize

We Need More Balance in Analysis Model Creation (e.g. FEA)

ChangeType or“Gender”

A Traditional CAD-Centric Process

CAD-Centric

Too Inefficient at Full Ship Scales

Nominal CADGeometry

Idealized SimulationGeometry

AnalysisModel (FEM)

PaveMeshDiscretize

We Need More Balance in Analysis Model Creation (e.g. FEA)

Add Req’d. Features

CAE-Centric

A CAE-Centric Process

More Efficient Creation of Shell Analysis Models

During Later Detailed Design Stages the Ship Product Model has a Manufacturing Flavor

The modern submarine has ~225,000 Structural Parts (of the 1.2 Million Overall Parts)

There are Over 5000 Parts in the Hull “Weight Account” Alone

At this scale, Extracting All Appropriate Structural Data and Information for Creating Simulation Models can be Onerous and very Time-Consuming