1 | Program Name or Ancillary Text eere.energy.gov

Water Power Peer Review

OTEC Cold Water Pipe-Platform Sub-System Dynamic Interaction Validation

Lockheed Martin CorporationMatthew.b.ascari@lmco.com 703-367-402911/02/2011

Matthew Ascari

2 | Wind and Water Power Program eere.energy.gov

Purpose, Objectives, & Integration

Project Purpose: Perform scale model testing of the OTEC platform and relatively large diameter cold water pipe in a dynamically controlled model basin facility to validate and improve existing dynamic computer models of the system.

[Describe the challenges, barriers, knowledge gaps, or problems that this project addresses.] Application of existing numerical modeling methods to analyze the OTEC system needs to be validated to minimize the risk to a pipe in the first at-sea pilot plant and in subsequent commercial plants.

[Describe how solving this problem relates to the Program’s mission and objectives.] Current Cold Water Pipe designs are based on fatigue and survival loads derived entirely from numerical models that have not been totally validated for a semi-submersible platform and CWP combination wherein the mass of the CWP is approximately equal to the platform. This is not normally the case for drilling and production risers used in offshore oil and gas production.

3 | Wind and Water Power Program eere.energy.gov

Technical Approach

[Describe the technical approach or methods used to achieve the project objective(s).] Subject a 1:50 scale model of the platform and cold water pipe to test conditions produced in a Model Basin facility. Analyze results and compare them to the numerical model predictions for this dynamic relationship.

[Identify key issues currently being addressed and their significance.] Team is looking at ways to accurately scale the cold water pipe properties such as bending stiffness, and how to reliably measure the responses in a way suitable for validation of numerical models.

[Emphasize unique aspects of approach.] Numerical models will “model the model”, i.e. the calibrated model properties will be used to construct the numerical model. Subsequently, the numerical model will be used to predict the behavior before the tests are run, i.e. the modeler will have no knowledge of the responses prior to executing the numerical model. This is called “blind analysis”. Subsequently, the numerical model will be modified to account for differences in the two, and a “best practices” document will be prepared to insure future modelers will properly analyze the CWP and platform behavior.

4 | Wind and Water Power Program eere.energy.gov

Plan, Schedule, & Budget

Schedule:• Initiation date: 4/2011• Planned completion date: 11/2012

– Date reflect a 6 month delay of contract start due to specific negotiation of terms. Model Basin availability is also a potential impact to schedule.

• [Milestones for FY10 and FY11] Development of Technical Specification and Selection of model basin facility for scale model testing.

• [Go/no-go decision points for FY12 and FY13] Scale Model Construction and Basin Testing

Budget: • The current planned budget is still accurate and the team is working with three model

basin facilities in a competitive selection process to ensure the best value for their part of this effort.

• As of 9/25/2011, roughly 6% or $61,474 of the $999,641 planned budget has been expended.

Budget History

FY2009 FY2010 FY2011

DOE Cost-share DOE Cost-share DOE Cost-share

0 0 0 0 $36K $25K