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OrcaFlex Manual
Version 9.4a
Orcina Ltd. Daltongate Ulverston Cumbria LA12 7AJ UK Telephone: +44 (0) 1229 584742 Fax: +44 (0) 1229 587191 E-‐mail: [email protected]w
ContentsCONTENTS
1
INTRODUCTION
11
1.1
Installing OrcaFlex
11
1.2
Running OrcaFlex
13
1.3
Parallel Processing
14
1.4
Distributed OrcaFlex
15
1.5
Orcina Licence Monitor
15
1.6
Demonstration Version
15
1.7
OrcaFlex Examples
15
1.8
Validation and QA
16
1.9
Orcina
16
1.10
References and Links
16
2
TUTORIAL
21
2.1
Getting Started
21
2.2
Building a Simple System
21
2.3
Adding a Line
21
2.4
Adjusting the View
22
2.5
Static Analysis
22
2.6
Dynamic Analysis
23
2.7
Multiple Views
23
2.8
Looking at Results
24
2.9
Getting Output
24
2.10
Input Data
24
3
USER INTERFACE
25
3.1
Introduction
25
3.1.1
Program Windows
25
3.1.2
The Model
25
3.1.3
Model States
26
3.1.4
Toolbar
27
3.1.5
Status Bar
28
3.1.6
Mouse and Keyboard Actions
28
3.2
OrcaFlex Model Files
31
3.2.1
Data Files
31
3.2.2
Text Data Files
32
3.2.3
Simulation Files
36
3.3
Model Browser
37
3.3.1
Model Browser Views
39
Contents
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3.4
Libraries
40
3.4.1
Using Libraries
40
3.4.2
Building a Library
43
3.5
Menus
44
3.5.1
File Menu
44
3.5.2
Edit Menu
45
3.5.3
Model Menu
46
3.5.4
Calculation Menu
47
3.5.5
View Menu
48
3.5.6
Replay Menu
49
3.5.7
Graph Menu
49
3.5.8
Results Menu
50
3.5.9
Tools Menu
50
3.5.10 Workspace Menu
50
3.5.11 Window Menu
51
3.5.12 Help Menu
51
3.6
3D Views
52
3.6.1
View Parameters
53
3.6.2
View Control
53
3.6.3
Navigating in 3D Views
54
3.6.4
Shaded Graphics
55
3.6.5
How Objects are Drawn
56
3.6.6
Selecting Objects
58
3.6.7
Creating and Destroying Objects
58
3.6.8
Dragging Objects
58
3.6.9
Connecting Objects
58
3.6.10 Printing, Copying and Exporting Views
59
3.7
Replays
59
3.7.1
Replay Parameters
60
3.7.2
Replay Control
60
3.7.3
Custom Replays
61
3.7.4
Custom Replay Wizard
61
3.7.5
Superimpose Times
63
3.8
Data Forms
63
3.8.1
Data Fields
64
3.8.2
Data Form Editing
64
3.9
Results
65
3.9.1
Producing Results
65
3.9.2
Selecting Variables
67
3.9.3
Summary and Full Results
67
3.9.4
Statistics
68
3.9.5
Linked Statistics
68
3.9.6
Offset Tables
69
3.9.7
Line Clashing Report
69
3.9.8
Time History and XY Graphs
70
3.9.9
Range Graphs
71
3.9.10 Offset Graphs
72
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Contents
3.9.12 Extreme Statistics Results
72
3.9.13 Presenting OrcaFlex Results
75
3.10
Graphs
76
3.10.1 Modifying Graphs
77
3.11
Spreadsheets
78
3.12
Text Windows
78
3.13
Workspaces
78
3.14
Comparing Data
79
3.15
Preferences
80
3.16
Printing and Exporting
82
4
AUTOMATION
83
4.1
Introduction
83
4.2
Batch Processing
83
4.2.1
Introduction
83
4.2.2
Script Files
85
4.2.3
Script Syntax
85
4.2.4
Script Commands
85
4.2.5
Examples of setting data
88
4.2.6
Handling Script Errors
93
4.2.7
Obtaining Variable Names
93
4.2.8
Automating Script Generation
93
4.2.9
Automating Text Data File Generation
96
4.3
Post-‐processing
97
4.3.1
Introduction
97
4.3.2
OrcaFlex Spreadsheet
98
4.3.3
Instruction Format
100
4.3.4
Pre-‐defined commands
101
4.3.5
Basic commands
102
4.3.6
Time History and related commands
103
4.3.7
Range Graph commands
103
4.3.8
Data commands
104
4.3.9
Instructions Wizard
105
4.3.10 Duplicate Instructions
107
5
THEORY
111
5.1
Coordinate Systems
111
5.2
Direction Conventions
112
5.3
Object Connections
113
5.4
Interpolation Methods
113
5.5
Static Analysis
115
5.5.1
Line Statics
115
5.5.2
Buoy and Vessel Statics
119
5.5.3
Vessel Multiple Statics
119
Contents
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5.6.1
Calculation Method
121
5.6.2
Ramping
123
5.7
Friction Theory
123
5.8
Spectral Response Analysis
126
5.9
Extreme Statistics Theory
127
5.10
Environment Theory
129
5.10.1 Buoyancy Variation with Depth
129
5.10.2 Current Theory
129
5.10.3 Seabed Theory
130
5.10.4 Seabed Non-‐Linear Soil Model Theory
131
5.10.5 Morison's Equation
137
5.10.6 Waves
138
5.11
Vessel Theory
145
5.11.1 Vessel Rotations
145
5.11.2 RAOs and Phases
146
5.11.3 RAO Quality Checks
147
5.11.4 Hydrodynamic and Wind Damping
149
5.11.5 Stiffness, Added Mass and Damping
151
5.11.6 Impulse Response and Convolution
152
5.11.7 Wave Drift Loads
153
5.12
Line Theory
155
5.12.1 Overview
155
5.12.2 Structural Model Details
156
5.12.3 Calculation Stages
157
5.12.4 Calculation Stage 1 Tension Forces
158
5.12.5 Calculation Stage 2 Bend Moments
159
5.12.6 Calculation Stage 3 Shear Forces
161
5.12.7 Calculation Stage 4 Torsion Moments
161
5.12.8 Calculation Stage 5 Total Load
162
5.12.9 Line End Orientation
162
5.12.10 Line Local Orientation
163
5.12.11 Treatment of Compression
164
5.12.12 Contents Flow Effects
164
5.12.13 Line Pressure Effects
166
5.12.14 Pipe Stress Calculation
167
5.12.15 Pipe Stress Matrix
168
5.12.16 Hydrodynamic and Aerodynamic Loads
169
5.12.17 Drag Chains
172
5.12.18 Line End Conditions
173
5.12.19 Interaction with the Sea Surface
173
5.12.20 Interaction with Seabed and Shapes
174
5.12.21 Clashing
175
5.13
6D Buoy Theory
177
5.13.1 Overview
177
5.13.2 Lumped Buoy Added Mass, Damping and Drag
179
5.13.3 Spar Buoy and Towed Fish Added Mass and Damping
180
5.13.4 Spar Buoy and Towed Fish Drag
182
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Contents
5.14
3D Buoy Theory
185
5.15
Winch Theory
186
5.16
Shape Theory
187
6
SYSTEM MODELLING: DATA AND RESULTS
189
6.1
Modelling Introduction
189
6.2
Data in Time History Files
190
6.3
Variable Data
192
6.3.1
External Functions
193
6.4
General Data
194
6.4.1
Statics
195
6.4.2
Dynamics
197
6.4.3
Integration & Time Steps
197
6.4.4
Explicit Integration
198
6.4.5
Implicit Integration
199
6.4.6
Numerical Damping
200
6.4.7
Response Calculation
201
6.4.8
Properties Report
201
6.4.9
Drawing
201
6.4.10 Results
202
6.5
Environment
202
6.5.1
Sea Data
202
6.5.2
Sea Density Data
203
6.5.3
Seabed Data
204
6.5.4
Wave Data
207
6.5.5
Data for Regular Waves
209
6.5.6
Data for Random Waves
209
6.5.7
Data for JONSWAP and ISSC Spectra
210
6.5.8
Data for Ochi-‐Hubble Spectrum
211
6.5.9
Data for Torsethaugen Spectrum
212
6.5.10 Data for Gaussian Swell Spectrum
212
6.5.11 Data for User Defined Spectrum
212
6.5.12 Data for Time History Waves
213
6.5.13 Data for User Specified Components
214
6.5.14 Data for Response Calculation
214
6.5.15 Waves Preview
214
6.5.16 Modelling Design Waves
215
6.5.17 Setting up a Random Sea
217
6.5.18 Current Data
219
6.5.19 Wind Data
221
6.5.20 Drawing Data
222
6.5.21 External Functions
223
6.5.22 Results
223
6.5.23 Wave Scatter Conversion
224
6.6
Solid Friction Coefficients Data
228
6.7
Vessels
229
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6.7.2
Vessel Types
239
6.7.3
Modelling Vessel Slow Drift
263
6.7.4
Vessel Response Reports
265
6.7.5
Vessel Results
267
6.8
Lines
269
6.8.1
Line Data
271
6.8.2
Line Types
286
6.8.3
Attachments
296
6.8.4
Rayleigh Damping
300
6.8.5
Line Results
303
6.8.6
Drag Chain Results
314
6.8.7
Flex Joint Results
315
6.8.8
Line Setup Wizard
315
6.8.9
Line Type Wizard
316
6.8.10 Chain
317
6.8.11 Rope/Wire
322
6.8.12 Line with Floats
325
6.8.13 Homogeneous Pipe
329
6.8.14 Hoses and Umbilicals
331
6.8.15 Modelling Stress Joints
333
6.8.16 Modelling Bend Restrictors
335
6.8.17 Modelling non-‐linear homogeneous pipes
337
6.8.18 Line Ends
339
6.8.19 Modelling Compression in Flexibles
342
6.9
6D Buoys
343
6.9.1
Wings
344
6.9.2
Common Data
345
6.9.3
Applied Loads
347
6.9.4
Wing Data
347
6.9.5
Wing Type Data
348
6.9.6
Lumped Buoy Properties
350
6.9.7
Lumped Buoy Drawing Data
351
6.9.8
Spar Buoy and Towed Fish Properties
352
6.9.9
Spar Buoy and Towed Fish Added Mass and Damping
354
6.9.10 Spar Buoy and Towed Fish Drag
355
6.9.11 Spar Buoy and Towed Fish Drawing
356
6.9.12 Shaded Drawing
356
6.9.13 Other uses
358
6.9.14 External Functions
358
6.9.15 Properties Report
358
6.9.16 Results
359
6.9.17 Buoy Hydrodynamics
361
6.9.18 Hydrodynamic Properties of a Rectangular Box
362
6.9.19 Modelling a Surface-‐Piercing Buoy
364
6.10
3D Buoys
367
6.10.1 Data
368
6.10.2 Properties Report
369
6.10.3 Results
369
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Contents
6.11.1 Data
371
6.11.2 Wire Properties
371
6.11.3 Control
372
6.11.4 Control by Stage
372
6.11.5 Control by Whole Simulation
373
6.11.6 Drive Unit
373
6.11.7 External Functions
374
6.11.8 Results
374
6.12
Links
375
6.12.1 Data
375
6.12.2 Results
377
6.13
Shapes
377
6.13.1 Data
378
6.13.2 Blocks
379
6.13.3 Cylinders
380
6.13.4 Curved Plates
381
6.13.5 Planes
382
6.13.6 Drawing
382
6.13.7 Results
383
6.14
All Objects Data Form
383
7
MODAL ANALYSIS
387
7.1
Modal Analysis Theory
388
8
FATIGUE ANALYSIS
391
8.1
Commands
392
8.2
Data
393
8.3
Load Cases Data for Regular Analysis
394
8.4
Load Cases Data for Rainflow Analysis
394
8.5
Load Cases Data for Spectral Analysis
395
8.6
Load Cases Data for SHEAR7
397
8.7
Components Data
397
8.8
Analysis Data
398
8.9
S-‐N and T-‐N Curves
399
8.10
Integration Parameters
400
8.11
Results
400
8.12
Fatigue Points
401
8.13
How Damage is Calculated
401
9
VIV TOOLBOX
405
9.1
Frequency Domain Models
405
9.1.1
VIVA
405
9.1.2
SHEAR7
410
Contents
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9.2.1
Wake Oscillator Models
420
9.2.2
Vortex Tracking Models
423
9.2.3
VIV Drawing
429
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Introduction, Installing OrcaFlex
1
INTRODUCTION
Welcome to OrcaFlex (version 9.4a), a marine dynamics program developed by Orcina for static and dynamic analysis of a wide range of offshore systems, including all types of marine risers (rigid and flexible), global analysis, moorings, installation and towed systems.
OrcaFlex provides fast and accurate analysis of catenary systems such as flexible risers and umbilical cables under wave and current loads and externally imposed motions. OrcaFlex makes extensive use of graphics to assist understanding. The program can be operated in batch mode for routine analysis work and there are also special facilities for post-‐processing your results including fully integrated fatigue analysis capabilities.
OrcaFlex is a fully 3D non-‐linear time domain finite element program capable of dealing with arbitrarily large deflections of the flexible from the initial configuration. A lumped mass element is used which greatly simplifies the mathematical formulation and allows quick and efficient development of the program to include additional force terms and constraints on the system in response to new engineering requirements.
In addition to the time domain features, modal analysis can be performed for individual lines and RAOs can be calculated for any results variable using the Spectral Response Analysis feature.
OrcaFlex is also used for applications in the Defence, Oceanography and Renewable energy sectors. OrcaFlex is fully 3D and can handle multi-‐line systems, floating lines, line dynamics after release, etc. Inputs include ship motions, regular and random waves. Results output includes animated replay plus full graphical and numerical presentation. If you are new to OrcaFlex then please see the tutorial and examples.
For further details of OrcaFlex and our other software, please contact Orcina or your Orcina agent. Copyright notice
Copyright Orcina Ltd. 1987-‐2010. All rights reserved.
1.1
INSTALLING ORCAFLEX
Hardware Requirements
OrcaFlex can be installed and run on any computer that has:
x Windows XP, Windows Vista or Windows 7. Both 32 bit and 64 bit versions of Windows are supported.
x If you are using small fonts (96dpi) the screen resolution must be at least 1024×768. If you are using large fonts (120dpi) the screen resolution must be at least 1280×1024.
However, OrcaFlex is a powerful package and to get the best results we would recommend:
x A powerful processor with fast floating point and memory performance. This is the most important factor since OrcaFlex is a computation-‐intensive program and simulation run times can be long for complex models.
x At least 2GB of memory. This is less important than processor performance but some aspects of OrcaFlex do perform better when more memory is available, especially on multi-‐core systems. If you have a multi-‐core system with a 64 bit version of Windows then you may benefit from fitting even more memory.
x A multi-‐core system to take advantage of OrcaFlex's multi-‐threading capabilities.
x As much disk space as you require to store simulation files. Simulation files vary in size, but can be 100's of megabytes each for complex models.
x A screen resolution of 1280×1024 or greater with 32 bit colour.
x A DirectX 9 compatible graphics card with at least 256MB memory for the most effective use of the shaded graphics facility.
x Microsoft Excel (Excel 2000, or later) in order to use the OrcaFlex automation facilities. This requires the 32 bit version of Excel.
Note: Although OrcaFlex is a 32 bit program, the 64 bit versions of Windows run 32 bit programs very
efficiently and have certain advantages over 32 bit versions of Windows. Most notably the 64 bit versions of Windows are able to make use of larger amounts of memory. This can benefit OrcaFlex, and indeed other programs. In addition we have found the 64 bit versions of Windows to be more effective at multi-‐threaded calculations. For these reasons we currently recommend 64 bit Vista/7 as the best platforms for running OrcaFlex.
Introduction, Installing OrcaFlex
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Installation To install OrcaFlex:
x You will need to install from an account with administrator privileges.
x If installing from CD, insert the OrcaFlex CD and run the Autorun.exe program on the CD (on many machines this program will run automatically when you insert the CD). Then click on 'Install OrcaFlex'.
x If you have received OrcaFlex by e-‐mail or from the web you will have a zip file, and possibly a number of licence files (.lic). Extract the files from the zip file to some temporary location, and save the licence files to the same folder. Then run the extracted file Setup.exe.
x You will also need to install the OrcaFlex dongle supplied by Orcina. See below for details.
For further details, including information on network and silent installation, click on Read Me on the Autorun menu or open the file Installation Guide.pdf on the CD. If you have any difficulty installing OrcaFlex please contact Orcina or your Orcina agent.
Orcina Shell Extension
When you install OrcaFlex the Orcina Shell Extension is also installed. This integrates with Windows Explorer, and associates the data and simulation file types (.dat and .sim) with OrcaFlex. You can then open an OrcaFlex file by simply double-‐clicking the filename in Explorer. The shell extension also provides file properties information, such as which version of OrcaFlex wrote the file and the Comments text for the model in the file. For details see the file CD:\OrcShlEx\ReadMe.htm on the OrcaFlex CD.
Installing the Dongle
OrcaFlex is supplied with a dongle, a small hardware device that must be attached to the machine or to the network to which the machine is attached.
Note: The dongle is effectively your licence to run one copy (or more, if the dongle is enabled for more
copies) of OrcaFlex. It is, in essence, what you have purchased or leased, and it should be treated with appropriate care and security. If you lose your dongle you cannot run OrcaFlex.
Warning: Orcina can normally resupply disks or manuals (a charge being made to cover costs) if they are lost
or damaged. But we can only supply a new dongle in the case where the old dongle is returned to us.
Dongles labelled 'Hxxx' (where xxx is the dongle number) must be plugged into the machine on which OrcaFlex is run. Dongles labelled 'Nxxx' can be used in the same way as 'Hxxx' dongles, but they can also be used over a network, allowing the program to be shared by multiple users. In the latter case the dongle should be installed by your network administrator; instructions can be found in the Dongle directory on the OrcaFlex CD.
Types of Dongle
Dongles are available for either parallel or USB ports, and these are functionally equivalent so far as OrcaFlex is concerned. In general, USB dongles are preferred, since they seem to be more reliable. In any case, parallel ports are becoming less common on new machines. By default, 'N' dongles can hold up to 10 OrcaFlex licences for use over a network. We can supply dongles with larger capacities on request.
Dongle Troubleshooting
We supply, with OrcaFlex, a dongle utility program called OrcaDongle. If OrcaFlex cannot find the dongle then this program may be used to check that the dongle is working correctly and has the expected number of licences. For details see the OrcaDongle help file.
The OrcaDongle program is included on the OrcaFlex CD, and you may choose to install it from the Autorun menu in the same way as OrcaFlex. It is also available for download from www.orcina.com/Support/Dongle.
Also on our website, users of network dongles may find the Orcina Licence Monitor to be useful. This application keeps track of the number of OrcaFlex licences claimed on a network at any time.
Diagnostics
If OrcaFlex fails to start, with the error that it can't obtain a licence, then please check the following.
x If you are using a network dongle, are all the licences in use? The Orcina Licence Monitor may be of use in determining this. If they are, you will need to wait until a licence becomes free before you can run OrcaFlex.
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Introduction, Running OrcaFlex
x If you are using a local dongle, is it plugged into your machine? If so, is the dongle device driver installed? You can check this by running OrcaDongle. If the driver is not present, it may have been uninstalled by another program: if so, you can fix this by Repairing the OrcaFlex installation (from the Windows Control Panel, select 'Add or Remove Programs' (XP) or Programs / Programs and Features (Vista), select the OrcaFlex entry, select Change then Repair). If this still fails, you can install the driver by downloading from our website, and running, the file Hasp-‐Setup.msi.
x Does the dongle you are using have an OrcaFlex licence on it? Again, you can check this with OrcaDongle. x Do you have a licence file for the dongle you wish to access? This file will be named Nxxx.lic or Hxxx.lic (where
xxx is the dongle number) and will be in the OrcaFlex installation folder. If not, then you should be able to copy the required file(s) from the root level of the OrcaFlex CD into the installation folder.
If none of these help, then please contact us at Orcina with a description of the problem. Ideally, please also email to us the diagnostics file named OrcLog.txt which OrcaFlex will have written on failing to find a licence. This file can be found in the folder "%appdata%/Orcina/OrcaFlex": to open this folder, select Start menu | Run... and enter the text between the quotes (including the '%' characters).
1.2
RUNNING ORCAFLEX
A shortcut to run OrcaFlex is set up on the Start menu when you install OrcaFlex (see Start\Programs\Orcina Software\).
This shortcut passes no parameters to OrcaFlex so it gives the default start-‐up behaviour; see below. If this is not suitable you can configure the start-‐up behaviour using command-‐line parameters, for example by setting up your own shortcuts with particular parameter settings.
Default Start-‐up
OrcaFlex has two basic modules: full OrcaFlex and statics-‐only OrcaFlex. A full OrcaFlex licence is needed for dynamic analysis.
When you run OrcaFlex it looks for an Orcina dongle from which it can claim an OrcaFlex licence (either a full licence or a statics-‐only licence). By default, it first looks for a licence on a local dongle (i.e. one in local mode and connected to the local machine) and if none is found then it looks for a licence on a network dongle (i.e. one in network mode and accessed via a licence manager over the network). This default behaviour can be changed by command-‐line parameters.
If OrcaFlex finds a network dongle and there is a choice of which licences to claim from it, then OrcaFlex displays a Choose Modules dialog to ask you which modules you want to claim. This helps you share the licences with other users of that network dongle. For example if the network dongle contains both a full licence and a statics-‐only licence then you can choose to use the statics-‐only licence, if that is all you need, so that the full licence is left free for others to use when you do not need it yourself. The Choose Modules dialog can be suppressed using command-‐line parameters.
Command Line Parameters
OrcaFlex can accept various parameters on the command line to modify the way it starts up. The syntax is: OrcaFlex.exe Filename Option1 Option2 ... etc.
Filename is optional. If present it should be the name of an OrcaFlex data file (.dat or .yml) or simulation file (.sim) and after starting up OrcaFlex will automatically open that file.
Option1, Option2 etc. are optional parameters that allow you configure the start-‐up behaviour. They can be any of the following switches. For the first character of an option switch, the hyphen character '-‐' can be used as an alternative to the '/' character.
Dongle Search switches
By default the program searches first for a licence on a local dongle and then for a licence on a network dongle. The following switches allow you to modify this default behaviour.
x /LocalDongle Only search for licences on a local dongle. No search will be made for network dongles.
x /NetworkDongle Only search for licences on a network dongle. Any local dongle will be ignored. This can be useful if you have a local dongle but want to use a network dongle that has licences for more modules.
Introduction, Parallel Processing
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Module Choice switch
This switch is only relevant if the dongle found is a network dongle and there is a choice of licences to claim from that dongle. You can specify your choice using the following command line switch:
x /DisableDynamics Choose the statics-‐only basic licence. This is sometimes useful when using a network dongle since it allows you to leave full licences free for other users when you only need a statics-‐only licence.
If you do not specify all the choices then the program displays the Choose Modules dialog to ask for your remaining choices. You can suppress this dialog using the following switch.
x /DisableInteractiveStartup Do not display the Choose Modules dialog. The program behaves the same as if the user clicks OK on that dialog without changing any module choices.
Batch Calculation switches
These switches allow you to instruct OrcaFlex to start a batch calculation as soon as the program has loaded. The following switches are available:
x /Batch Start a batch calculation as soon as the program has loaded. The batch calculation will contain all the files specified on the command line (you can have more than one) in the order in which they are specified. You can use relative paths which will be relative to the working directory.
x /CloseAfterBatch Instructs the program to close once the batch is complete.
x /BatchAnalysisStatics, /BatchAnalysisDynamics specify what type of analysis to perform to the specified files. If these parameters are missing then the program defaults to dynamic analysis.
Process Priority switches
These switches determine the processing priority of OrcaFlex. The available switches are /RealtimePriority, /HighPriority, /AboveNormalPriority, /NormalPriority, /BelowNormalPriority, /LowPriority.
ThickLines switch
The /ThickLines switch allows you to specify a minimum thickness for lines drawn on OrcaFlex 3D View windows. For example using the switch /ThickLines=5 forces OrcaFlex to draw all lines at a thickness of at least 5. If no value is specified (i.e. the switch is /ThickLines) then the minimum thickness is taken to be 2.
This switch has been added to make OrcaFlex 3D Views clearer when projected onto a large screen. ThreadCount switch
The /ThreadCount switch allows you to set the number of execution threads used by OrcaFlex for parallel processing. For example /ThreadCount=1 forces OrcaFlex to use a single execution thread which has the effect of disabling parallel processing.
1.3
PARALLEL PROCESSING
Machines with multiple processors or processors with multiple cores are becoming increasingly common. OrcaFlex can make good use of the additional processing capacity afforded by such machines. For up to date information on hardware choice for OrcaFlex please refer to www.orcina.com/Support/Benchmark.
OrcaFlex performs the calculations of the model's Line objects in parallel. This means that, interactively at least, performance is only improved for models with more than one Line object. However, for models with more than one Line performance is significantly improved.
Both batch processing and fatigue calculations process their jobs and load cases concurrently, using all available processor cores.
Note, however, that the OrcaFlex spreadsheet is currently only able to make use of a single processor core. We plan to address this limitation in a future release.
Thread count
OrcaFlex manages a number of execution threads to perform the parallel calculations. The number of these threads (the thread count) defaults to the number of physical processor cores available on your machine as reported by the operating system. This default will work well for most cases. Should you wish to change it you can use the Tools | Set Thread Count menu item. The thread count can also be controlled by a command line switch.
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Introduction, Distributed OrcaFlex
Hyperthreading
Some Intel processors offer a technology called hyperthreading. Such processors can process multiple execution threads in parallel by making use of under-‐used resources on the processor. Hyperthreaded processors appear to the operating system as 2 distinct, logical processors.
Sadly, the real world performance of such chips does not live up to the marketing hype. At best this technology can give improvements of around 10-‐20%. However, the performance of hyperthreading under OrcaFlex varies considerably with the OrcaFlex model being analysed. In the worst cases using hyperthreading results in performance twice as slow as without!
For this reason we recommend that you don't attempt to use hyperthreading when running OrcaFlex. By default OrcaFlex will use as many threads as there are true physical cores available to your system.
To help understand this consider a dual processor, dual core machine with hyperthreading support. The operating system will recognise 8 processors. Of these processors, 4 are true physical processor cores and the other 4 are virtual hyperthreaded processors. Accordingly OrcaFlex will default to using 4 calculation threads.
1.4
DISTRIBUTED ORCAFLEX
Distributed OrcaFlex is a suite of programs that enables a collection of networked, OrcaFlex licensed computers to run OrcaFlex jobs, transparently, using spare processor time. For more information about Distributed OrcaFlex please refer to www.orcina.com/Support/DistributedOrcaFlex. Distributed OrcaFlex can be downloaded from this address.
OrcaFlex can also make use of machines with multiple processors using parallel processing technology.
1.5
ORCINA LICENCE MONITOR
The Orcina Licence Monitor (OLM) is a service that monitors the current number of OrcaFlex licences claimed on a network in real time. Other programs that use the OrcaFlex programming interface (OrcFxAPI) such as Distributed OrcaFlex and the OrcaFlex spreadsheet are also monitored. You can obtain information on each licence claimed that includes:
x Network information: the computer name, network address and the user name.
x Licence information: the dongle name, the dongle type (network or local) and the time the licence was claimed. x Program information: which modules are being used, the version, and the location of the program which has
claimed the licence (usually this is OrcaFlex.exe but it can be Excel.exe for the OrcaFlex spreadsheet for example).
OLM can be downloaded from www.orcina.com/Support/OrcinaLicenceMonitor.
1.6
DEMONSTRATION VERSION
For an overview of OrcaFlex, see the Introduction topic and the tutorial.
The demonstration version of OrcaFlex has some facilities disabled Ȃ you cannot calculate statics or run simulation, and you cannot save files, print, export or copy to the clipboard. Otherwise the demonstration version is just like the full version, so it allows you to see exactly how the program works.
In particular the demonstration version allows you to open any prepared OrcaFlex data or simulation file. If you open a simulation file then you can then examine the results, see replays of the motion etc. There are numerous example files provided on the demonstration DVD. These example files are also available from www.orcina.com/SoftwareProducts/OrcaFlex/Examples.
If you have the full version of OrcaFlex then you can use the demonstration version to show your customers your OrcaFlex models and results for their system. To do this, give them the demonstration version and copies of your
OrcaFlex simulation files. The demonstration version can be downloaded from
www.orcina.com/SoftwareProducts/OrcaFlex/Demo.
1.7
ORCAFLEX EXAMPLES
OrcaFlex is supplied with a DVD containing a comprehensive collection of example files. These examples can also be found at www.orcina.com/SoftwareProducts/OrcaFlex/Examples.
Introduction, Validation and QA
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1.8
VALIDATION AND QA
The OrcaFlex validation documents are available from www.orcina.com/SoftwareProducts/OrcaFlex/Validation.
1.9
ORCINA
Orcina is a creative engineering software and consultancy company staffed by mechanical engineers, naval architects, mathematicians and software engineers with long experience in such demanding environments as the offshore, marine and nuclear industries. As well as developing engineering software, we offer a wide range of analysis and design services with particular strength in dynamics, hydrodynamics, fluid mechanics and mathematical modelling. Contact Details Orcina Ltd. Daltongate Ulverston Cumbria LA12 7AJ UK Telephone: +44 (0) 1229 584742 Fax: +44 (0) 1229 587191 E-‐mail: [email protected] Web Site: www.orcina.com Orcina Agents
We have agents in many parts of the world. For details please refer to www.orcina.com/ContactOrcina.
1.10
REFERENCES AND LINKS
References
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API. Comparison of Analyses of Marine Drilling Risers. API Bulletin. 2J.
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Introduction, References and Links
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