Drag test on cylinders with helical
| Project acronym: | HyIII-NTNU-8 |
| Name of Group Leader: | Shan Huang |
| User-Project Title: | Drag test on cylinders with helical |
| Facility: | Towing Tanks |
| Proceedings TA Project: | Cylinder drag reduction by the use of helical grooves |
| Data Management Report: | Data Management Reports Page You will need to login to view this page |
User Project Objectives:
It is generally understood that grooves and dimples are different from general roughness. As far as it is known, no investigations had been carried out on the drag reduction of the kind of helical grooves dealt with in this project.
The objective of the project was to carry out fixed cylinder drag tests in the MARINTEK towing tank to confirm whether the helical grooves can indeed reduce the drag loading on cylinders in the critical and post-critical Reynolds number ranges.
User-Project Achievements and
difficulties encountered:
- Thanks to the support of MARINTEK staff, the model tests were completed on schedule.
- Data of good quality were logged, and the detailed analysis work is being carried out.
- A term of four people from Glasgow went to MARINTEK for the tests. The project is extremely useful for the people to become aware of and learn from the procedure and practice of MARINTEK.
- Some difficulties were encountered, such as the rigidity of the supporting frame and the calibration of the load cells. The effects of these issues are being analyzed
Highlights important research results:
- More than 100 runs were executed in the towing tank. The preliminary results confirm that the grooves do reduce the drag loading on cylinders. This is an important confirmation.
- Rough cylinder tests were also carried out, and the results show that the drag reduction is less pronounced when the cylinder surface is very rough.