On October 7, 2005 a limited scope tank test was completed at IOT in Newfoundland Canada to explore the hydrodynamic effects resulting from differing transom immersion. The model used was the FYD D546 Volvo Open 70 Model at a scale of 1:3.2. For this experiment, the model was tested upright only with keel and bulb package at 0 cant and with no rudders.

This comprehensive data set provides an accurate experimental baseline for use in validating computation simulation tools. To this end the results include both experimentally recorded forces, sink and trim but also data from pressure tap data located on a buttock line and detailed photographic and video summaries of the completed tests.

The flotation of the model was altered relative to a standard VO70 trim to achieve a range of transom immersion studies and to maintain consistent as possible wetted lengths. Four flotations were studied with flotation AA being the lightest/lowest immersion and flotation DD the heaviest deepest immersion.

The model geometry is provided in Rhino 3DM Version 5 format with the origin located at Station 5 and DWL with X +ve forward, Y +ve to starboard and Z +ve down. The full scale station spacing is 2.132m. The appropriate configuration trims for the tested flotations are outlined in the configuration sheets as both freeboard deltas and origin sink and trim values.

Model markings are located in reference to the DWL orientation and are labelled clearly in the photographs.

Buttocks on the transom are positioned at 250mm full scale increments.



Test matrix including trim moments:

Tank Geometry Full Scale:

Tank Geometry Model Scale:

Pressure tap results:

Raw tank data comparison:

Raw data text files archive:

Tank photos from 3 views archive:

MP4 format test video archive:

Quick flow comparison of transom:

Turbulence Stimulation Summary:


If you use any of the data provided on this page, please use the following information for your citation.

Author: Farr Yacht Design

Title: Farr Volvo70 Immersed Transom Study

Date: 2005

Publisher: Sailing Yacht Research Foundation [distributor]

Electronic Retrieval Location: http://sailyachtresearch.org/resources/farr-volvo70-immersed-transom-study/

Farr Volvo70 Immersed Transom Study by Farr Yacht Design is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.

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