Dolfiman
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I am pleased to share with you my new version 3.1 of Gene-Hull Dinghy , a spreadsheet application oriented for an early stage project : this version is mostly motivated by a new approach of the keel line shape (i.e. hull bottom center line for a dinghy) now generated with a curvature regularly decreasing from bow to aft transom where it becomes zero. I think this concept is very well suited for a dinghy sailing either in displacement mode or in planing mode with a smooth transition between the two modes. Reguraly is the key word, because steps of curvature are not optimal for a smooth flow of the water behind the stagnation zone. And regularly decreasing means that the more the planing mode is developing, the less the curvature of the hull bottom remaining in contact with the water.
The second main improvement is about the hull lines representation more adapted to the planing mode.
>>> The standard representation with the waterlines at various heights is informative for the displacement mode at low speed but not much for the skimming mode on the water surface. The dynamic lift being a lot in relation with the deadrise angulation within each sections, I found useful to add the « deadrise » lines, i.e. the lines joining the points of the sections sharing the same local « deadrise » angle : 2°, 4°, 6°, etc...,20°.
>>> This representation, especially showing the shape of the central flatness (transversal angles < 2°) from the pointy bow to the aft transom, makes easier to guess how the planing mode can occur and progress.
My thoughts about these two points + the other usual conditions for a dinghy design (lightness, sail ratio and sail carrying power, intrinsic stability) are detailed in the introduction of the « Examples » document attached.
These are the 2 main upgrades of this 3.1 version + some other minor improvements as usual for a new version : automatical computation of the criteria about the intrinsic dynamic stability (I simplify there, the use of Gene-Stab is no longer necessary), additionnal parameters to define the sailplan. For all other features of the application, I stay in line with the previous version so I think the user can easily capture and appropriate the novelty of this one.
In addition, I slightly updated the VPP (Velocity prediction) in connection, becoming Gene-VPP Dinghy 3.1 although, for the User, the data to input are unchanged.
As usual, also here attached are the updated User guides and Examples covering a broad range of typical designs (inc. hulls « inspired by » Laser, 5o5, 49er, Melges MC Scow, …), of which input data are also in the storage sheets ready for a copy paste. The input data for the dinghy example named D1,0 are in place in the 2 applications. You may be also interested by the offsets of the Dinghy Examples, here attached also.
For the beginner of Gene-Hull : it is recommended to first test the influence of each adimensional parameters, without changing the geometrical data, to see and learn about the influence of each one, in conjunction with the explanations given in the User Guide. Very easy to do and quite fun as well as instructive.
For the more advanced user : you can take advantage of one of the examples showed in the « Examples » document, of which input data are stored in the « Hulls storage » sheet , to start a new project.
It is a free and open source spreadsheet application, developed on a support itself free and widespread (Open Office Calc 4.0.1) : to open and use an ods file, you need either Open Office or Libre office on your PC, if necessary to download according to :
ODS File Extension - What is an ods file and how do I open an ods file? | OpenTheFile
By hoping this new version can be helpful for your early stage projects. As a remind, you can also be interested by (updated versions) :
For a Saiboat project :
Gene-Hull Sailboat 3.3 and its post applications Gene-Stab and Gene-VPP | Boat Design Net
For a Sailing Catamaran project :
Gene-Hull Catamaran 3.0 and SA-VPP catamaran 1.0 | Boat Design Net
For a Canoe or Peapod project :
Gene-Hull Canoe 3.0 - new version for Canoe, Peapod or Pointu projects | Boat Design Net
VPP for Power catamaran :
SA-VPP power catamaran | Boat Design Net
(the files attached to quote #8)
The second main improvement is about the hull lines representation more adapted to the planing mode.
>>> The standard representation with the waterlines at various heights is informative for the displacement mode at low speed but not much for the skimming mode on the water surface. The dynamic lift being a lot in relation with the deadrise angulation within each sections, I found useful to add the « deadrise » lines, i.e. the lines joining the points of the sections sharing the same local « deadrise » angle : 2°, 4°, 6°, etc...,20°.
>>> This representation, especially showing the shape of the central flatness (transversal angles < 2°) from the pointy bow to the aft transom, makes easier to guess how the planing mode can occur and progress.
My thoughts about these two points + the other usual conditions for a dinghy design (lightness, sail ratio and sail carrying power, intrinsic stability) are detailed in the introduction of the « Examples » document attached.
These are the 2 main upgrades of this 3.1 version + some other minor improvements as usual for a new version : automatical computation of the criteria about the intrinsic dynamic stability (I simplify there, the use of Gene-Stab is no longer necessary), additionnal parameters to define the sailplan. For all other features of the application, I stay in line with the previous version so I think the user can easily capture and appropriate the novelty of this one.
In addition, I slightly updated the VPP (Velocity prediction) in connection, becoming Gene-VPP Dinghy 3.1 although, for the User, the data to input are unchanged.
As usual, also here attached are the updated User guides and Examples covering a broad range of typical designs (inc. hulls « inspired by » Laser, 5o5, 49er, Melges MC Scow, …), of which input data are also in the storage sheets ready for a copy paste. The input data for the dinghy example named D1,0 are in place in the 2 applications. You may be also interested by the offsets of the Dinghy Examples, here attached also.
For the beginner of Gene-Hull : it is recommended to first test the influence of each adimensional parameters, without changing the geometrical data, to see and learn about the influence of each one, in conjunction with the explanations given in the User Guide. Very easy to do and quite fun as well as instructive.
For the more advanced user : you can take advantage of one of the examples showed in the « Examples » document, of which input data are stored in the « Hulls storage » sheet , to start a new project.
It is a free and open source spreadsheet application, developed on a support itself free and widespread (Open Office Calc 4.0.1) : to open and use an ods file, you need either Open Office or Libre office on your PC, if necessary to download according to :
ODS File Extension - What is an ods file and how do I open an ods file? | OpenTheFile
By hoping this new version can be helpful for your early stage projects. As a remind, you can also be interested by (updated versions) :
For a Saiboat project :
Gene-Hull Sailboat 3.3 and its post applications Gene-Stab and Gene-VPP | Boat Design Net
For a Sailing Catamaran project :
Gene-Hull Catamaran 3.0 and SA-VPP catamaran 1.0 | Boat Design Net
For a Canoe or Peapod project :
Gene-Hull Canoe 3.0 - new version for Canoe, Peapod or Pointu projects | Boat Design Net
VPP for Power catamaran :
SA-VPP power catamaran | Boat Design Net
(the files attached to quote #8)
Attachments
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Gene-Hull Dinghy 3.1_2024 01.ods4.7 MB · Views: 485
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Gene-Hull Dinghy 3.1_User Guide_2024 01.pdf1.9 MB · Views: 568
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Gene-Hull Dinghy 3.1_Examples_2024 01.pdf3.5 MB · Views: 544
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Gene-VPP Dinghy 3.1_2024 01.ods4.3 MB · Views: 433
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Gene-VPP Dinghy 3.1_User Guide_2024 01.pdf455.8 KB · Views: 501
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Offsets of the dinghies examples.pdf1.6 MB · Views: 555