yades
Senior Member
- Joined
- Aug 23, 2006
- Posts
- 95
- Reaction score
- 13
- Location
- italy
After having performed an extensive research on the Internet and viewed forums (even the present one under boat design topic), sites and all relevant literature appearing on the web I came to the conclusion that there is a great deal of information available however not comprehensive enough so as to cover systematically and concurrently the evaluation of a propulsion system of a hard chine planing hull in all principal aspects which are Resistance-Power-Propeller matching. 
PC, related spreadsheet and dedicated software has made this evaluation easier enough to be worked out, however, practical empirical or semi-empirical methods available, together with a methodical approach, seem to be (at least from what has been gathered from the web….) not commonly accessible and far from embracing the subject thoroughly. :idea:
As with regard to Hull Drag and Thrust evaluation I found Dingo Tweedie effort with his spreadsheet remarkable and extremely useful so as the one from Hawaii Marine Company I must say. However, it would be of further and more valuable assistance to my opinion gather some more interesting informations concerning losses involved in power generation and in power transmission and some other supporting procedures in prop calculations either using the Bp-δ charts or Kt-Kq charts from Wageningen Type B prop curves.
All this, at the moment, seem to be scuttered over various papers and books, undoubtedly of extremely valuable assistance, however specific on each distinct subject. Resistance and Propeller Dimensioning are, more or less, treated as ....two distinct subjects !!……. :?:
Fair enough !…..
This thread will endeavour to provide an opportunity to cover the basic elements/requirements on the subject in a more analytical approach partly with infos/supports readily available and partly based on supplementary practical and semi empirical elements generally available but valuable in providing a complete sequence of events on the above mentioned assessment procedure. All based on first principle of naval architecture and currently available informations which must be familiar to a general power boat enthusiast
and/or naval architect/yacht designer/marine engineer.
I believe a major technical contribution could be offered in that respect on this forum via comments, technical support, reference papers, links, suggestions and specific but useful technical data, which could herewith been added so as to enhance anybody knowledge on the above mentioned subject.
The first step which I will shortly add hereinafter will be “PART 1”, outlining the main parameters and ratios involved in hull resistance calculation and thrust.
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:!:
the view herewith expressed is that of the author and is reputed being true to the extend of his knowledge. Indeed if any adverse opinion is deemed to be outlined and argumented It should be substantiated in practice for further & better understanding. Moreover, all information hereby provided in terms of templates, graphs, technical documentations, empirical or semi-empirical formulae, spreadsheets and so an so forth are to be considered on “as is “ basis without warranty of any kind, either expressed or implied and the user is required to verify that all aspects have been covered correctly for the purpose intended.
Nevertheless, every effort is being made hereinafter so as to assure accuracy and validity of all technical informations provided.
Yades
PC, related spreadsheet and dedicated software has made this evaluation easier enough to be worked out, however, practical empirical or semi-empirical methods available, together with a methodical approach, seem to be (at least from what has been gathered from the web….) not commonly accessible and far from embracing the subject thoroughly. :idea:
As with regard to Hull Drag and Thrust evaluation I found Dingo Tweedie effort with his spreadsheet remarkable and extremely useful so as the one from Hawaii Marine Company I must say. However, it would be of further and more valuable assistance to my opinion gather some more interesting informations concerning losses involved in power generation and in power transmission and some other supporting procedures in prop calculations either using the Bp-δ charts or Kt-Kq charts from Wageningen Type B prop curves.
All this, at the moment, seem to be scuttered over various papers and books, undoubtedly of extremely valuable assistance, however specific on each distinct subject. Resistance and Propeller Dimensioning are, more or less, treated as ....two distinct subjects !!……. :?:
Fair enough !…..
This thread will endeavour to provide an opportunity to cover the basic elements/requirements on the subject in a more analytical approach partly with infos/supports readily available and partly based on supplementary practical and semi empirical elements generally available but valuable in providing a complete sequence of events on the above mentioned assessment procedure. All based on first principle of naval architecture and currently available informations which must be familiar to a general power boat enthusiast
and/or naval architect/yacht designer/marine engineer. I believe a major technical contribution could be offered in that respect on this forum via comments, technical support, reference papers, links, suggestions and specific but useful technical data, which could herewith been added so as to enhance anybody knowledge on the above mentioned subject.
The first step which I will shortly add hereinafter will be “PART 1”, outlining the main parameters and ratios involved in hull resistance calculation and thrust.
-------------------------
:!:
the view herewith expressed is that of the author and is reputed being true to the extend of his knowledge. Indeed if any adverse opinion is deemed to be outlined and argumented It should be substantiated in practice for further & better understanding. Moreover, all information hereby provided in terms of templates, graphs, technical documentations, empirical or semi-empirical formulae, spreadsheets and so an so forth are to be considered on “as is “ basis without warranty of any kind, either expressed or implied and the user is required to verify that all aspects have been covered correctly for the purpose intended.
Nevertheless, every effort is being made hereinafter so as to assure accuracy and validity of all technical informations provided.
Yades
..) ..secondly I'd assume being not in the spirit of a forum suggesting to ......"hire a professional"