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[jsr363-experts] Re: Request for clarification on Unit commensurability

  • From: Werner Keil < >
  • To: " " < >
  • Subject: [jsr363-experts] Re: Request for clarification on Unit commensurability
  • Date: Tue, 16 Dec 2014 15:00:11 +0100

Actually it's very easy to run all of the underlying page through Google
Translate:
https://translate.google.de/translate?sl=de&tl=en&js=y&prev=_t&hl=de&ie=UTF-8&u=http%3A%2F%2Fwww.dagego.de%2Finfo_grundlagen_waermeuebertragung.html%23Groessen&edit-text=

It explains, the only constant (3600) is the factor to calculate seconds to
hours. Actually something Quantity can handle by itself via
Quantities.getQuantity(60, SECOND).to(HOUR) ;-D

I may revisit the code if I have time (probably not before Christmas) but I
hope it helps you understand which quantities they used.

Werner

On Tue, Dec 16, 2014 at 2:51 PM, Werner Keil 
< >
 wrote:
>
> Maybe this helps you:
> http://www.energysavingtrust.org.uk/content/our-calculations
> It refers to a "W/m2K" which goes alongside a sentence and further
> formulas in the Dagego sample
> >Interessant ist auch die Frage, um wie viel Kelvin die Temperatur in
> einer Stunde in einem 1000L Speicher steigt, wenn man >nur 9,5 KW zur
> Verfügung hat. Dafür ist es nötig, die Formel umzustellen nach:
> Translated:
> "How many K per hour does the temperature rise in a 1000 l boiler if you
> have 9.5 KW to heat?"
>
> Another simple calculation:
> http://www.endmemo.com/physics/heatengine.php
> based on Carnot's work, it  contains some "constant" 1, which as of now,
> we could not deal with either.
>
> Quantity.subtract(Quantity) exists, so as a workaround we do have
> AbstractQuantity.ONE.subtract(someQuantity);
>
>
>
> Werner
>
>
> On Tue, Dec 16, 2014 at 1:51 PM, Martin Desruisseaux <
>  >
>  wrote:
>>
>>  Le 16/12/14 21:39, Werner Keil a écrit :
>>
>> We don't make money from this, but I don't think the company that does (
>http://www.dagego.de/) got this totally wrong.
>>
>> I do not said that they are wrong. I said that I'm pretty sure that the
>> Boltzmann constant (or something equivalent) is hidden somewhere in their
>> equations. They may have managed to rewrite their equations in such a way
>> that the numerical value of their constant become 1, and consequently
>> omitted it. This may be bright. But a numerical value of 1 does not mean a
>> dimensionless quantity: we can have 1 second, 1 metre, 1 kWh, etc. So the
>> fact that we can omit a multiplication in the computation of a
>> *numerical* value does not mean that we can omit that multiplication in
>> the computation of the *unit* of that value.
>>
>>     Martin
>>
>>


[jsr363-experts] Request for clarification on Unit commensurability

Martin Desruisseaux 12/15/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Werner Keil 12/15/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Martin Desruisseaux 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Werner Keil 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Martin Desruisseaux 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Werner Keil 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Werner Keil 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Martin Desruisseaux 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Werner Keil 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Werner Keil 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Martin Desruisseaux 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Werner Keil 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Martin Desruisseaux 12/16/2014

[jsr363-experts] Re: Request for clarification on Unit commensurability

Werner Keil 12/16/2014
 
 
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