Study on the Contra-Rotating Propeller system design and full-scale performance prediction method

In this study, Telfer’s GEOSIM method for the computation of ship resistance at full scale has been applied by CFD (Computational Fluid Dynamics) approach. For this purpose, the KCS (KRISO Container Ship) hull has been investigated numerically with k-ε turbulence model for three different scales and full scale analyses by URANS (Unsteady Reynolds Averaged Navier-Stokes) method. Full scale ship resistance has been predicted using the numerical results computed at different model scales by Telfer’s GEOSIM method. The numerical results at three scales have also been extrapolated separately to that at full scale by ITTC 1978 performance prediction method. An experimental study has also been carried out at a model scale for validation. The results by Telfer’s GEOSIM method have been calculated almost in full compliance with those of CFD approach. While the difference between the results of CFD and those of ITTC extrapolation method is about 5% at full scale, the difference between the results of CFD and those of Telfer’s GEOSIM method has been found to be less than 1% at full scale. In addition, this method has been applied to estimate the nominal wake coefficient at full scale from model scales. A very good correlation has also been found for nominal wake coefficient.

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Ship-Model Correlation of Powering Performance on USS Oliver Hazard Perry, FFG-7 Class

Marine Technology and SNAME News ◽

10.5957/mt1.1983.20.1.35 ◽

1983 ◽

Vol 20 (01) ◽

pp. 35-52

Author(s):

Everett L. Woo ◽

Gabor Karafiath ◽

Gary Borda

Keyword(s):

Performance Prediction ◽

Prediction Method ◽

Model Tests ◽

Trial Data ◽

Full Scale ◽

Ship Model ◽

Single Screw ◽

Post Trial ◽

Model Correlation

Standardization trials were conducted on USS Oliver Hazard Perry (FFG-7) in May 1978. From the results of the trial data and the post-trial model correlation experiments which simulated the trial conditions, the powering correlation allowance of 0.00045 was obtained for the FFG-7. It should be noted that the pretrial model tests used the design correlation allowance of 0.0005 to predict full-scale powering performance. In addition, the powering performance was predicted using the "1978 ITTC Performance Prediction Method for Single Screw Ships."

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Telfer’s GEOSIM Method Revisited by CFD

10.3940/rina.ijme.2019.a4.563 ◽

2019 ◽

Vol 161 (A4) ◽

Keyword(s):

Fluid Dynamics ◽

Performance Prediction ◽

Prediction Method ◽

Full Scale ◽

Numerical Results ◽

Navier Stokes ◽

Container Ship ◽

Ship Resistance ◽

Full Compliance ◽

The Difference

In this study, Telfer’s GEOSIM method for the computation of ship resistance at full scale has been applied by CFD (Computational Fluid Dynamics) approach. For this purpose, the KCS (KRISO Container Ship) hull has been investigated numerically with k-ε turbulence model for three different scales and full scale analyses by URANS (Unsteady Reynolds Averaged Navier-Stokes) method. Full scale ship resistance has been predicted using the numerical results computed at different model scales by Telfer’s GEOSIM method. The numerical results at three scales have also been extrapolated separately to that at full scale by ITTC 1978 performance prediction method. An experimental study has also been carried out at a model scale for validation. The results by Telfer’s GEOSIM method have been calculated almost in full compliance with those of CFD approach. While the difference between the results of CFD and those of ITTC extrapolation method is about 5% at full scale, the difference between the results of CFD and those of Telfer’s GEOSIM method has been found to be less than 1% at full scale. In addition, this method has been applied to estimate the nominal wake coefficient at full scale from model scales. A very good correlation has also been found for nominal wake coefficient.

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