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Hello, Ive been confused sometimes about the feedwater exits. Is its enthalpy always equal to the sat. Liq of the extracted steam? When using the pump method, i noticed it is not, assuming the given state when both extracted and feedwater mixed

Great video Dr. Mantufel! Thank you!

I have written out the solution myself, but when I tried to post the Drive link here CZcams keeps shadowbanning this comment. For now I will just leave my explanation of how I got equation of the line and how to express r as a function of Z. The part about getting r(z) might confuse some people. It certainly confused me at first. I did not use the method explained in this video. My approach was slightly different. What I had done as seen on my solution, is that I drew a 2D projection view of the Y and Z axes as shown in the question's diagram. The outer edge of the cone (highlighted in green on my solution) was considered to be a line within the set coordinate system and the equation for this line was determined. We can see that the green line is going down (as you go from left to right) therefore its gradient is negative. We can also see that the line intercepts the vertical axis (in this case the Z axis) at h, therefore the y-intercept is h. It intercepts the horizontal axis at "a" and therefore the gradient of the line can be determined. It is rise over run and since we know that the lengths of "h" and "a" are the "rise" and the "run" respectively, the gradient of the line is -h/a. The full equation of the line is Z=-h/a*y+h The trick now is understanding that Z is our variable that we need to integrate with respect to, as our infinitesimal element has a dZ in it. That immediately gives us a clue that we have to somehow somewhere integrate with respect to Z. We also need to be cognizant of the fact that the quantity "r" which is the radius of the infinitesimal element, is a CHANGING quantity. It's not a constant as the infinitesimal element (the small quarter cone slice indicated on the diagram) can be placed anywhere in the whole quarter cone so the r value can be higher or lower. This tells us that "r" is a VARIABLE and therefore we cannot treat it as a constant (generally you can pull constants outside the integral when solving but you can never do that with variables). We will have to integrate with respect to "r" either directly or indirectly. As previously mentioned, we have a dZ as our infinitesimal element's height, so immediately this tells us that we have to find some way to represent the quantity r as a function of Z. Once we do that, the hardest part of the problem is solved. If you look at the 2D sketch I drew, "r" in that 2D sketch would essentially be horizontal lines that start from the Z axis and end at the actual line (determined by the equation above). The LENGTH of those horizontal lines (r) is given by the y value of the green line. This would essentially mean that the "r" quantity can be expressed as equivalent to y in the function of the straight line. Essentially all that means is that you take the equation above, and you make y the subject of the formula and then you can simply call "y" r(z) because that function now describes the length of r as it changes with respect to Z or the Z axis (so as the infinitesimal element moves up and down). Finally that would leave us with r(z) = a[1-(z/h)] And this equation does satisfy the common sense checks outlined in this video. When Z=h then r must be 0. When Z=0 then r must be a. From there the question is pretty easy but expressing r as a function of Z allows us to integrate r (which is a CHANGING quantity) indirectly with respect to Z. Generally that's how you're supposed broadly think when doing applied maths problems like this.

This make this realistic than i was thought in class. Thanks man

Thank you very much.

Can this equation work for the center of mass

Thank you so much Manteufel! You were my thermodynamics professor in college and your lectures are great. Had to brush up on this chart and this really helped.

I seriously cannot commend you enough. Clear and concise. I wish I had found you at the start of the semester. Thank you.

Great video, thanks very much. Seriously, this video should appear higher on the recommended list.

Where can i get the excel sheets for the calculation? Thank you

You're a legend man

Thank you very much sir

i have a problem right after adding the add-ins thermodynamic where it brings me to the VBA windows and the ThisWorkbook.VBProject.HelpFile = ThisWorkbook.Path & "\ThermoTablesHelp.chm" is in yellow. what can i do ?

I got full credit for this in transport phenomena 2. It still makes me angry that peter is a tubby boy whose wife is angry at him and hes teaching our class. Peter should stop lecturing about what we know from undergraduate and start teaching the students he has today. If peter were smart with words he would stop calling the equations animals. When peter talks about the power of words, i think about calculating the power in kcals stored in his body fat. Peter sweats when he takes a lot of steps. Maybe peter should build an excel spreadsheet to track his daily caloric intake.

you lack an explanation: "because we have more nitrogen" why? you dont explain why we have "more" nitrogen. "then we need to fix the nitrogen" I wonder what your class avg is? probably one of those teachers that have to use a bell curve to prevent the class from failing. P.S. if you are one of those teachers who implements a curve in the class because class performance is poor, newsflash is not because your students are dumb. Its because you teach poorly.

hi, thanks for the nice video. can you send me the add in?

Thanks 😊, Really helped

Why would air heat up in uniform fashion when the delta T with the refrigerant varies so much? Doesn't make sense.

How can 2 to 3 is constant pressure when we add the heat? Shouldnt it be the reverse where pressure increae with the increae of heat?

love you

Thank you, Dr.Manteufel. First I was your student back in UTSA and learned Heat Transfer. Now, I am teaching Heat transfer at North Park University Chicago, IL.

Thank you so much professor

THANK YOUUUUU !!!! Litteraly discovering the software the evening before my exam Your saving my ass (maybe)

Well illustrated and to the point. It was difficult to find a good review of both y and x bar. Going in to take my FE next week and needed this refresher. Thank you

Many thanks! Good info.

Thank you (^^)/

You explained it so well!! Thank you!!!

super useful

33:01 Re= G(D)/miu

Do PVT have to equal zxy respectively? Or they can be anyone? I tried PVT as xyz, and I ended up getting R/V x R/P after partial differentiating

why - i mean wh y the 3 is negative

thank you sir

Why is air temperature increasing lineary? This is not what I learnt about T-A (temperature-area) diagram

How we calculate x4 ?

goat

هل من مصل على النبي محمد صل الله عليه وسلم وبارك الصلاة الإبراهيمية

When i did this question i had to multiply the given mass by 9.81 to get the weight and that was how i got correct answers but your process was right otherwise but could be a different question type so idk

friction for turbulent is not 0.316Re^0.25 BUT 0.316/Re^0.25, correct it???????

Are the reaction moments in these 2 hinges negligible in real-life? Or is it just the conditions given in the problem?

very helpful, thank you so much!

Live long

💖

@Randall Manteufel, at 30:38, shouldnt we have O2 in the product? considering that we have EXCESS AIR

❤

What about finding temperature Ty?