Sub Project 7 - Simulation-based concept design

Participants and resources

Trond Johnsen (WP4 and leader offshore case), Sverre-Anders Alterskjær (WP2 and leader deepsea case), Haakon-Elizabeth Lindstad (WP1), Torstein Ingebrigtsen Bøe (WP3), Evert Bouman (WP5)

Schedule:

2017

Introduction

Naval architects have always faced the challenge of demonstrating the effect of potential design changes when vessels are brought into operation. The actual effects are highly dependent on the operating profile of the vessel, i.e. where, when and how it will sail. Traditional methods and tools for evaluating designs do not offer an opportunity to handle complex issues of this sort.
Virtual testing will improve the estimation of vessel performance by simulating the interaction of hydrodynamics, power production and service equipment in a realistic operating context. This is of particular importance for assessing the benefits and challenges of alternative hull forms, new power production systems and alternative service equipment arrangement. Examples include bow forms for improved handling of added resistance, dual-fuel and LNG engines, fuel-cells and batteries, and new cranes and winches. Improved ability to rapidly analyse and verify new design solutions represents a significant contribution to the competitive position of the involved industrial partners in terms of developing innovative ships that are more energy efficient and have increased operability.
Virtual testing can be done at different levels of detail, from the dynamic time-domain simulations with full physical models and milliseconds time-steps to the quasi-static discrete-event simulations with average value calculations and hour-long timesteps. In this concept design project we will focus on the quasi-static simulations, which allows us to evaluate the ship performance over years of operation.
The project will focus on two different industry cases and involve all five work packages, as illustrated below:

 

Objectives

• Improving early stage design decisions by enabling simulation of long-term performance of new ship technology and design solutions
• Perform two different case studies
o One deep-sea vessel with shipowner's perspective
o One offshore service vessel with shipdesigner's perspective

Case study process

Both case studies will follow a similar iterative process:
1) Select existing benchmark vessel and develop/gather models of this
2) Run simulations in GYMIR with realistic operational profiles
3) Compare simulation results with Full-scale and Model-scale data for the benchmark vessel
3) Define KPI's and Functional Requirements for next generation benchmark vessels
4) Identify promising Concept Solutions for further evaluation
5) Model the new ship concepts and run simulations in GYMIR
6) Compare results of new concepts with benchmark vessels
7) Estimate the environmental and economic impact of the new concepts

 

WP contributions

All WP's will be involved in this project. In order to succeed with the case studies, the following contributions are planned from each of the WP's:

 

Case 1 – Ship-owner

Case 2 – Ship designer

WP1

- Develop simplified versions of analytical and numerical models enabling comparison of multiple alternative designs in the feasibility phase of the project.

 

- Develop a process methodology to identify the functional requirements and the Key Performance Indicators. Including how to describe them in qualitative and quantitative terms

WP2

- Hydrodynamic modelling of case vessel, including added resistance in waves validation study

- Study of the sensitivity of modelling methods on prediction of overall routing/operational powering performance

- Comparisons versus empirical prediction of speed loss and/or power increase due to waves and wind using in-service monitoring data

- Hydrodynamic modelling of case vessel, including added resistance in waves validation study

- Study of the sensitivity of modelling methods on prediction of overall routing/operational powering performance

- Comparisons versus empirical prediction of speed loss and/or power increase due to waves and wind using in-service monitoring data (if available)

WP3

- Develop models for main engines including fuel consumption and emissions.

- Develop models of hybrid power plant for deep sea vessels including PTI/PTO shaft generator/motor.

- Develop simplified models of a DP vessels power plant to reduce computational complexity. The models should include fuel consumption and emissions.

- Develop models for hybrid power plants with energy storage.

- Develop methods to optimize configurations for the power plant based on operational mode.

- Develop methods to compute average fuel consumption for a time interval with fluctuating power demand.

WP4

- Develop KPI reporting and analytics for ship-owners in GYMIR

- Enhance scenario modelling functionality in GYMIR to include more deep sea vessel modes and operational logic

- Validate overall simulated performance against full scale data from deep sea vessel

- Enhance scenario modelling functionality in GYMIR to include more offshore vessel modes and operational logic

- Integrate power system models into GYMIR

- Validate overall simulated performance against model and full scale data from an offshore vessel

WP5

- Test the STEAM model on the alternative designs. Improve the model if required. Perform a full environmental and & economical due diligence of the selected designs

 

- Establish the emission curves for all the exhaust gases as a function of MCR

- Include the emission curves in the STEAM model

- Use the Steam model to perform a full environmental and & economical due diligence of the alternative power setups.

Deliverables


1. Simulation-based concept design methodology
2. Quasi-static simulation components
3. Integrated simulation framework
4. Industry test case analysis and reports
5. Scientific publication focusing on the case studies