Enhanced Design of Search and Rescue Craft
25/11/2015 1
Federico Prini
Simon Benson
School of Marine Science and Technology
Newcastle University
ENHANCED DESIGN OF
SEARCH AND RESCUE CRAFT
Enhanced Design of Search and Rescue Craft
“Enhanced Design of Search and Rescue Craft”
Address the structural design of Search and Rescue craft
to further improve design and operational practice
Explore how new technologies and approaches can improve
the in-service performance on lifeboats
25/11/2015 2
Enhanced Design of Search and Rescue Craft
Background
25/11/2015 3
Maximum allowable speed
for a given sea state
Enhanced Design of Search and Rescue Craft
Research Strategy
Systematic approach based on:
Theoretical:
Numerical model global hydrodynamic loads and structural response
Experimental:
Towing tank tests acceleration, body motions and hull loads
Full-scale sea trials acceleration and strain
Drop tests of sections bottom pressure gradient
Focus on the RNLI’s Severn Class
Aim for results with wider applicability
25/11/2015 4
Enhanced Design of Search and Rescue Craft
25/11/2015 5
SMALL-SCALE TESTS
DROP TESTSFULL-SCALE
TESTS
Continuous Model
Segmented Model “2D” Hull Sections
Instrumented Lifeboat
MOTION RAOs
MOTION RAOs
MOTION RAOs
LOAD RAOs
ACCELERATION ACCELERATION
PANEL PRESSURE
PANEL PRESSURE
STRUCTURAL RESPONSE
FEM
PANEL PRESSURE
MAESTRO
MAESTRO-Wave
MOTION RAOs
LOAD RAOs
ACCELERATION
PANEL PRESSURE
MAESTRO-FE
STRUCTURAL RESPONSE
Enhanced Design of Search and Rescue Craft
Finite Element Model
25/11/2015 6
FE package MAESTRO
Full-ship global model
14000 elements
Material: fibre reinforced
composites (Glass and
Glass/Aramid, epoxy resin,
foam core)Length overall 17.00 m
Length waterline 15.50 m
Beam max 5.62 m
Depth 2.52 m
Draught 1.37 m
Displacement (full load) 42 t
Speed max 25 kn
Enhanced Design of Search and Rescue Craft
Hydrodynamic Performance
3 potential theory codes:
25/11/2015 7
• 2D strip theory
• 2.5D strip theory
• 3D panel method
Frequency Domain
Output:
• Panel pressures
• Motion RAOs
• Hull Girder
Load RAOs
Enhanced Design of Search and Rescue Craft
Results
25/11/2015 8
Federico Prini
Simon Benson
Richard W Birmingham
Robert S Dow
School of Marine Science
and Technology
Newcastle University
“Seakeeping Analysis of a High-Speed
Search and Rescue Craft by Linear Potential Theory”
Holly J Phillips
Peter J Sheppard
RNLI
Jesus Mediavilla Varas
Lloyd’s Register
Enhanced Design of Search and Rescue Craft
Validation
Systematic approach based on:
Numerical model global hydrodynamic loads and
structural response
Towing tank tests acceleration, motions
and hull loads
Full-scale sea trials motions, acceleration and strain
Drop tests of sections bottom pressure distribution
25/11/2015 9
Enhanced Design of Search and Rescue Craft
Summary
Address the structural design of Search and Rescue
Craft
Systematic approach based on theoretical and
experimental methods
Numerical model integrating hydrodynamic and
structural analysis has been completed
Experimental tests necessary to validate the numerical
model and identify its predictive capability
25/11/2015 10
Enhanced Design of Search and Rescue Craft
25/11/2015 11