Recent content by FNMwacki

I'm sorry, I've edited some portions of previous posts but not others. I should have just left it alone and added another post. For surface areas i have: 16.125 inch diameter is a 1.344 ft diameter, .67 ft radius 23.375 inch height is a 1.95 ft height 1.42 sqft = ∏*(.67)^2...

I included it at 210 degrees because the water is not boiling but the evaporation loss is still there, this more or less told me the minimum i need to fire the element just to maintain 210F. (this is higher than the percent needed to boil when not including that radiation from the surface, i...

Generally people shoot for between 1gal and 1.25gal per hour boil off...so my assumptions are: 10 gallons heating volume 15.5 gallons heating vessel capacity 5500 watts from electric element 3.41 BTU/watt 23.375 inches keg height 16.125 inches keg diameter This gives me: 1.418 sqft for surface...

The keg is 23.375 inches high and 16.125 inches in diameter...thanks for your input, i kind of thought that was the case (that the boiling loss is or was close to the evaporation loss). edit: I also should mention that i scale the side surface area of the keg to the amount of water I'm heating...

That is exactly my next step (actually monitor losses while boiling), I just know that I live in a very dry climate that also effects the rate of boil off...my goal was to find a generic formula that might work for other ambient temps and humidity as a basis. Thanks all for your input!

Of course i don't NEED it :) I just like solving problems and getting as close as I can...and i totally understand this is a very compicated problem, I'm just looking for some guidelines to be as close as i can. Like I said, I'm brewing beer, people did it for thousands of years before...

Hi all, I'm a homebrewer and I'm trying to find the boil off rate in gal/hour when using an electric heating element in my kettle. If I'm using a 5500Watt heating element at 100%, I'm inputting about 312 BTU/min...Using this site and the table for the losses due to evaporation and radiation...

Ya, thanks for the input, but i already know the expectation should not exist... Or you could see Wiki as Mark pointed out...

Ok, thanks again for the help. Looking back now I probably could have been more clear what I was doing in the original post...

You are correct, f(x; 0, 1) = 1/(pi * (1 + x^2)) is my PDF, but i am trying to prove the Expectation of this pdf, so ∫ x*f(x)dx from -∞ to ∞ I pull out the 1/pi, use U substitution for (1+x^2), so i have (1/pi)*∫ x/(2xu) du, where du=2xdx => dx=du/2x then i call pull out the 2 from the...

Thanks again for the response, but I'm not sure I follow the point you are trying to make here... If the integrals diverge, and knowing Cauchy Distribution is symmetric, we can use the reflection property and also say it is 2*(infinity - 0)...

PS - Thanks for the "Helpful symbols" ;)

Thanks for the response, I see your point, but even evaluating as such I would get (∞ -0) + (0 - ∞) = (∞ - ∞) which is still undefined...

Is it sufficient to state that both these limits (at positive and Neg infinity) = infinity and that (infinity - infinity) is not defined??

I've evaluated the integral of my problem to be (ln(x^2 + 1)/2*pi), and need to evaluate this at infinity and negative infinity...not sure where to proceed from here to evaluate these limits. Actually i need to prove that it doesn't exist (I am proving the first moment of the Cauchy...