Enhanced Design of Search and Rescue Craft

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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

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Enhanced Design of Search and Rescue Craft

Background

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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

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Enhanced Design of Search and Rescue Craft

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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

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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:

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• 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

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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

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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

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Enhanced Design of Search and Rescue Craft

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