Short answer

Incorporate CFD simulations early in the design process to predict and optimize catamaran performance at drift, leveraging the demonstrated accuracy for resistance and other key forces.

Field: Modelling
Source: Journal of Fluids Engineering (2019)
Method: Comparative simulation study
Evidence: Strong effect

Advanced Computational Fluid Dynamics (CFD) models can reliably predict hydrodynamic forces on catamarans at drift angles, with resistance estimations showing a standard deviation of approximately 3.5%. This modelling research insight is drawn from a 2019 study published in Journal of Fluids Engineering. Using Comparative simulation study, researchers explored how this design variable affects real-world outcomes. The key design takeaway: Incorporate CFD simulations early in the design process to predict and optimize catamaran performance at drift, leveraging the demonstrated accuracy for resistance and other key forces.

Study

ModellingHigh ImpactStrong effect

CFD simulations accurately predict catamaran drift forces with 3.5% resistance variance

Journal of Fluids Engineering · 2019

Key Findings

01All simulations generally captured the main flow field features.
02Grid resolution significantly impacted the onset of coherent structures.
03Turbulence models influenced vortex dynamics.
04Hydrodynamic load predictions showed good agreement across different simulations, with a standard deviation of ~3.5% for resistance and ~7% for lateral force and yaw moment.
05Both Level-Set (LS) and Volume of Fluid (VoF) methods captured wave-induced vortices, with LS showing more defined and longer-lasting vortices.

Application

Design takeaway

Incorporate CFD simulations early in the design process to predict and optimize catamaran performance at drift, leveraging the demonstrated accuracy for resistance and other key forces.

How to apply

When designing or analyzing multihull vessels, utilize CFD to simulate performance at various drift angles. Compare results from different turbulence models and grid strategies, and validate against available experimental data where possible.

Project actions

01When using CFD for your design project, clearly state the software and models used.
02Always aim to compare your CFD results with any available experimental data or established benchmarks.

Method & Evidence

AimTo assess the capability of state-of-the-art Computational Fluid Dynamics (CFD) tools in accurately predicting the flow field and hydrodynamic loads on a multihull catamaran operating at non-zero drift angles.

MethodComparative simulation study

ProcedureThree research institutes independently performed CFD simulations of a Delft 372 catamaran in static drift conditions using their proprietary codes. Various grid types (structured vs. unstructured), turbulence models (e.g., DES), and free surface capturing methods (LS vs. VoF) were employed. Results were compared against each other and validated against experimental fluid dynamics (EFD) data.

ContextNaval architecture and marine engineering, specifically hull form design and performance prediction.

Variables

IV["Drift angle","Grid resolution","Turbulence model","Free surface capturing method (LS vs. VoF)"]

DV["Hydrodynamic loads (resistance, lateral force, yaw moment)","Flow field characteristics (vortices, separation)"]

CV["Hull geometry (Delft 372 catamaran)","Advance speed","Water density and viscosity"]

Strengths & Limitations

Strengths

+Comparison of multiple CFD codes and methodologies.
+Validation against experimental data.
+Focus on a relevant and complex flow scenario (3D separated flow at drift).

Limitations

CFD simulations can be computationally expensive and require significant expertise to set up and interpret correctly. The accuracy is dependent on the quality of the mesh and the chosen turbulence model.

Reliability & validity

The reliability is supported by the agreement between multiple independent CFD simulations and the validation against experimental data. Validity is high for predicting the specific flow conditions studied, but may be limited for other vessel types or conditions.

Think critically

To what extent can the findings of this study be generalized to different types of marine vessels or to more complex sea states beyond static drift?

Design Principles

"Validate computational models against experimental data to ensure predictive accuracy for critical design parameters."

This level of accuracy in CFD simulations allows designers to reduce reliance on expensive physical model testing during the early stages of design. It enables faster iteration and optimization of hull forms for improved performance and stability in various operating conditions.

What This Means for Your Design

Computer simulations of boat shapes (CFD) can accurately predict how much push a catamaran boat feels when it's moving sideways, with very similar results from different computer programs.

How to use in your project

1.Reference this study when justifying the use of CFD for predicting hydrodynamic forces or fluid dynamics in your design project.

Add to My Project

Quick Cite

Paragraph starter

This study demonstrates the effectiveness of Computational Fluid Dynamics (CFD) in predicting hydrodynamic loads on multihull vessels, showing that advanced simulations can achieve high accuracy, with resistance predictions exhibiting a standard deviation of approximately 3.5%. This supports the use of CFD as a reliable tool for design optimization in naval architecture.

Source

Journal of Fluids Engineering

Assessment of Computational Fluid Dynamics Capabilities for the Prediction of Three-Dimensional Separated Flows: The DELFT 372 Catamaran in Static Drift Conditions

journal · 2019

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Questions About This Research

What does the research say about cfd simulations accurately predict catamaran drift forces with 3.5% resistance variance?: Incorporate CFD simulations early in the design process to predict and optimize catamaran performance at drift, leveraging the demonstrated accuracy for resistance and other key forces. Evidence: Journal of Fluids Engineering (2019).
Why does "CFD simulations accurately predict catamaran drift forces with 3.5% resistance variance" matter for design?: This level of accuracy in CFD simulations allows designers to reduce reliance on expensive physical model testing during the early stages of design. It enables faster iteration and optimization of hull forms for improved performance and stability in various operating conditions.
How can designers apply this research?: Incorporate CFD simulations early in the design process to predict and optimize catamaran performance at drift, leveraging the demonstrated accuracy for resistance and other key forces.
What were the main findings?: All simulations generally captured the main flow field features.. Grid resolution significantly impacted the onset of coherent structures.. Turbulence models influenced vortex dynamics.. Hydrodynamic load predictions showed good agreement across different simulations, with a standard deviation of ~3.5% for resistance and ~7% for lateral force and yaw moment.
What research method was used?: Comparative simulation study.
How strong is the evidence?: Evidence strength is rated Strong effect, based on a 2019 journal from Journal of Fluids Engineering.
What should I do differently in my next project?: When designing or analyzing multihull vessels, utilize CFD to simulate performance at various drift angles. Compare results from different turbulence models and grid strategies, and validate against available experimental data where possible.
What are the limitations?: The study focused on static drift conditions; dynamic drift scenarios might yield different results. The accuracy of free surface capturing methods can vary.