powerHull online resistance prediction software

powerHull is a web-based resistance prediction software. It started as a personal project to learn Python and now decided to post it here to get your feedback. It is all written in python using the Django web framework. You can access it from here powerhull.azurewebsites.net
Because it is hosted on Microsoft's cloud free tier service, sometimes accessing the website might take a bit. Current features include:
- Bare hull resistance prediction
- Appendage resistance estimation (rudders, shafts, struts, trim-tabs)
- Air drag estimation
- Adding resistance margin
- Setting overall propulsion efficiency and transmission loss for estimating total required power
- User registration for storing/retrieving parameters
- Metric/Imperial units
- Saving results locally in csv format (Excel compatible)

Currently implemented methods:
- Original Savitsky method including whisker spray resistance, lift and drag from trim tabs, porpoising stability assesment
- Modified Savitsky with the Blount & Fox M-Factor for hump-speed region
- Mercier & Savitsky for pre-planing speeds
- VTT Series
- Series 62

I hope you can find this work useful and maybe comment here with some feedback regarding improvements and future additions.

Link does not work :\

Since there was no interest for over a month a decided to shut down the web-site. There was some cost involved with the database used by the app and with no users and feedback there was no point on continuing. The code is still there so maybe I will try to make a stand-alone windows application for anyone interested.

It is not easy (I don't know how to do it) to give an opinion about a web page and what is exposed in it, when it is not possible to access it. And @captncoop had already warned you but you, inexplicably, ignored him. Well, you know better than anyone what you're interested in doing or not doing.

TANSL said:

It is not easy (I don't know how to do it) to give an opinion about a web page and what is exposed in it, when it is not possible to access it. And @captncoop had already warned you but you, inexplicably, ignored him. Well, you know better than anyone what you're interested in doing or not doing.

Click to expand...

Hosting a web based application requires a server running Python (if written in Python) or Microsoft's IIS (if written in C#), plus a database to store users and the data they are producing. Providers such as Microsoft Azure or Amazon have a "development" tier that allows the developers to host their web based app for free but with great limitations. One of those is that the server is idle when users do not access it. This means that the first user that attempts to access may wait up to 2-3 min in order the server to start up. Another limitation is storage which is effectively deleted every time the server goes in idle mode. This is to limit the resources of the cloud server for free tier users. Keeping a project in a paid tier has a cost that I am not willing to cover for a project that was actually an attempt to learn Python and maybe provide something useful for the community here. I kept it online for about a month in Azure's free tier which was not very practical for the end user and paid for the database to store the data. Unfortunately I had no feedback from anyone over this period and so I decided to terminate it. If someone has in mind an alternative provider to host it I will try again. Otherwise when I get some free time I may transfer all the code to a desktop based app which has no provider cost for any of you to try and maybe comment.

It is very kind of you to give all that complete explanation, which I do not understand, fortunately, at all. But perhaps all of this explains, in part, why no one has responded to your request for feedback. Try it again and in another way, if you really want to share something with the rest of the world, not just for a month, but forever. Please be patient with us because in this forum you always get answers, even if it is late.

TANSL said:

It is very kind of you to give all that complete explanation, which I do not understand, fortunately, at all. But perhaps all of this explains, in part, why no one has responded to your request for feedback. Try it again and in another way, if you really want to share something with the rest of the world, not just for a month, but forever. Please be patient with us because in this forum you always get answers, even if it is late.

Click to expand...

I never implied that I was expecting something from this forum that I did not get. I tried to explained to you that the choice of using the free tier of the cloud provider proved to be impractical both for me and the end users due to several limitations. Although I liked the idea of a web based app, I am moving the code to a desktop based to avoid these limitations. If you can suggest an alternative provider for hosting a python web based application that has no limitations to no commercial projects I am happy to re-try.

I'm sorry I can't help you on these issues because of websites, hosts, servers, etc, I don't know anything either.

vkstratis said:

I never implied that I was expecting something from this forum that I did not get. I tried to explained to you that the choice of using the free tier of the cloud provider proved to be impractical both for me and the end users due to several limitations. Although I liked the idea of a web based app, I am moving the code to a desktop based to avoid these limitations. If you can suggest an alternative provider for hosting a python web based application that has no limitations to no commercial projects I am happy to re-try.

Click to expand...

raspberry Pi can host website for free (well, cost of pi)