density to ABW and ABV calculator

Distillation methods and improvements.

Moderator: Site Moderator

Post Reply
spencoid
Novice
Posts: 64
Joined: Fri Jun 30, 2017 7:26 pm

density to ABW and ABV calculator

Post by spencoid »

Not totally sure if this works but I wanted to have a handy calculator to convert density to ABW and ABV so i can do a quick accurate check of my distillate. Would like others to check it and see if it seems right.

I have been making very high strength vodka and gin and have been flavoring with pepper and other strong stuff. The result is that the potency is not apparent so I wanted a really accurate check on proof.

My refractometer is useless at high proof and the float hydrometer seems accurate but is a bit of a bitch to get it to not stick etc. The calculator is written in perl TKX so the exe is quite a large file but the script that drives it is small. Some day I am going to get a Raspberry Pi tablet and a book on Perl for Raspberry which will allow me to make all sorts of cool things for my still but i am waiting for two crowd funded items for this. Too old to learn to write smart phone apps. Hopefully i will be able to run my still from the tablet with touch screen and a huge variety of options graphics utilities all in one place.

I bought some 100 ml volumetric flasks which should make measuring density easy.

Anyway here is the calculator. I zipped it in hopes of being able to attach it.

BTW, i am maing some really good gin and vapor infused vodkas and even my (very critical) friends think some of it is actually drinkable :)
spencoid
Novice
Posts: 64
Joined: Fri Jun 30, 2017 7:26 pm

Re: density to ABW and ABV calculator

Post by spencoid »

next improvement is to add temperature correction. i have read a lot online about how to do this and it gets a little complicated. i am thinking of just correcting the final ABV using lookup tables made from charts i can find online. a few questions: if i ony really want correct ABV do i need to correct the ABW or density first or can i just use the correction tables for ABV over temperature? i can not find any formula for correcting density of ethanol / water mixtures over temperature nor can i find them for ABW, just ABV. I do understand that this is not a simple problem and that the various official tables were not trivial to calculate.

Anyone know of a formula that is good enough or does it make more sense to just copy the tables? It is not that big of a deal to enter a huge table into my program as an array. However there is still the question as to whether this table for correction of alcoholometers can be used to correct the ABV that i get from converting density to ABV and not correcting the density first.
spencoid
Novice
Posts: 64
Joined: Fri Jun 30, 2017 7:26 pm

Re: density to ABW and ABV calculator

Post by spencoid »

i found the information i need in an old Bureau of Standards document and have made a lookup table for temps from 10 to 40C. i found other references in chemical engineering handbooks and the table i made agrees with them accurately. now i just need to add the table to my program do a lookup and interpolate to the nearest tenth of a percent ABW.
hpby98
Site Donor
Site Donor
Posts: 314
Joined: Thu Jun 01, 2017 3:38 pm
Location: New Zealand

Re: density to ABW and ABV calculator

Post by hpby98 »

Hey. Nothing looks to be attached to your original post.

I’d be interested to see how it’s going
spencoid
Novice
Posts: 64
Joined: Fri Jun 30, 2017 7:26 pm

Re: density to ABW and ABV calculator

Post by spencoid »

the exe is pretty big because it is written in perl and was made into an exe with perlapp which make large files since the perl interpreter needs to be in the mix. so i think it must have exceeded some limit ans the attachment did not really happen. here is a link on my web server http://www.spencerserolls.com/density-to-percent.zip" onclick="window.open(this.href);return false;" rel="nofollow i hope to find time to add temperature correction in a day or two. have written the table, just need to figure out how to reference it and interpolate the values. also want to add output of proof which is just a division by two so that should be easy :)
also will add a tare for the volumetric flask and also an option to enter grams of a 100 ml flask (or other size) so you can just weigh the flask enter the value and get ABW ABV an proof corrected for temperature. will eventually make the settings sticky so you just have to enter weight and temp.
spencoid
Novice
Posts: 64
Joined: Fri Jun 30, 2017 7:26 pm

Re: density to ABW and ABV calculator

Post by spencoid »

i think i have my density to ABW ABV calculator working. it now displays proof as well just for completeness. i have tested it with a bunch of values comparing to available tables from the US Bureau of Standards and it seems right. I am not great at math (used to be when i used it a lot) so my algorithms have been derived experimentally but i do think i got it right. i would like to see if others think the program is working. if it is really working correctly, i will add a bunch of other features to make it a more useful program. i would like to sell it for a very reasonable price so i am going to cripple the test version a little making it work only with some values.

anyone interested in trying it?
Post Reply