r/ChemicalEngineering • u/25thMohammed • 2d ago
Student Mass Transfer
Just started my 3rd year in ChE, and Mass Transfer is on the schedule this semester.
For anyone who’s survived it: any tips, trickiest topics to watch out for?
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u/Background-Friend410 2d ago
"Survived", we really need to stop with this terminology lol, it's another course and it's challenging, if you made it this far you"ll be fine. Good luck
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u/25thMohammed 2d ago
Thanks, I hope so. I just meant that so far we've been drowned in dozens of correlations and empirical equations to estimate many things.
Should I actually be trying to understand/memorize every detail behind these correlations, or is knowing when and how to apply them usually enough?
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u/NanoWarrior26 2d ago
You will not use 90+% of the things you are learning at any point once you graduate.
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u/ForeverLeading1142 2d ago
Just be ready for your wrists to break from solving and paracetamol for the headache of the different constants, which you need to practice a whole lot for. But also, its fun. We chem engs have Stockholm syndrome.
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u/Traveller9536 2d ago
Very similar to heat transfer
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u/RevolutionEasy1975 2d ago
I didn’t know people took heat and mass transfer separate tbh
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u/Traveller9536 2d ago
My school went on the quarter system, so our classes are only 10 weeks long. It was probably split up because of that
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u/al_mc_y 1d ago
For me the light bulb moment in Transport Phenomena was the realisation that all the equations for heat and mass transfer are essentially the same. I felt like i was being taught separate and possibly unrelated things (more to remember). But when it finally struck me that while the preferred symbols change and even co-ordinate systems - the equations are largely the same. Choose the most appropriate coordinate system for your application and plug it in to that version of the heat or mass transfer equations and you're off to the races.
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u/DasaniMessiah Batch Chemical Plants/10 years experience 2d ago
Just remember things naturally flow from a higher concentration to a lower concentration. Also separation is typically very expensive. Even more so the closer boiling points are. Don’t even get me started on azeotropes.
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u/Strategic_Science 1d ago
Understand the equations instead of memorizing. If you relate one solid real life concept to each equation in mass transfer, you've already learned 50% of the stuff. Remember the assumptions, and exceptions. Make a habit of using the equations to solve questions- this way your concepts will be strong.
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u/YesICanMakeMeth PhD - Computational Materials Engineering 2d ago
Wasn't drastically different than heat xfer, IMO. Might slay you if you are one of those people that find moles confusing.
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u/25thMohammed 2d ago
Well, Heat Transfer also on my schedule this semester.
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u/YesICanMakeMeth PhD - Computational Materials Engineering 2d ago
Hmm, I can't remember if that was the case for me or not. There's nothing forcing them to be sequential but I thought they were for me.
The hard part for most people is identifying the boundary conditions. From there, it's typically a routine calculus/differential equation problem. If you're really worried just get the textbook and start flipping through some examples. Brush up on calculus if you struggled.
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u/derioderio PhD 2010/Semiconductor 2d ago
When I was an undergrad we did fluid dynamics in one semester, and heat+mass transfer in another semester. Where I went to grad school though, I TA'ed their undergraduate class that taught momentum, heat, and mass transfer all in a one semester class. And their textbook was Bird, Stewart, and Lightfoot for an undergrad class. That was pretty brutal for the students.
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u/YesICanMakeMeth PhD - Computational Materials Engineering 2d ago
I did grad school at the same university as undergrad and undergrad was partitioned as you describe while the grad school transfer class covered all three. I believe that was our grad school textbook - the professor had had one of them on his committee LOL.
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u/derioderio PhD 2010/Semiconductor 2d ago
BSL is a great textbook for reference, or for a grad level class. For my grad class we used Deen's Analysis of Transport Phenomena, and I thought it was a really good textbook. I liked it because it covered techniques that you generally don't see as an undergrad that I have found to be useful:
- Fourier transform method of solving separable PDEs
- Similarity transforms
- Regular and singular perturbation methods
- Thin film equations and lubrication flow
- A more formalized and general approach to tensor and vector based calculus, including the very useful index notation method
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u/Turbulent_End_6887 2d ago
Think about the effect of NIL on college football. That is causing Mass Transfer. Go from football players to something considerably smaller--molecules.
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u/Ecstatic_Chain_9488 1d ago
Navier-Stokes,Bernoulli, Fick, and Stefan are the only flow daddies you’ll ever need.
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u/Derrickmb 2d ago
They’re only going to teach you 1D math. Also the example of concentration coming in from the surface of a pipe as fluid is flowing is a good example to memorize. Also works for calculating heat loss or gain along a length of pipe
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u/r2o_abile Pulp & Paper / 4 YOE 1d ago
Solve questions so you can understand how to think and what to apply what you learn.
IMO, not much different from Heat Transfer if you understand the difference between amount and mass.
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u/w_it_taker 1d ago
Only tip is office hours. It's wild to me how often this is underutilized. Give your best shot on the homework and then bring it in to go over it one on one with the prof or the TA depending on your school. This was a cheat code for me to make it through engineering school and now I'm happily employed.
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u/Acceptable-Caramel69 1d ago
Lowk treat it like heat transfer because boundary layer theory is everywhere
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u/Afraid_Bake3940 15h ago
Don't be afraid, just go for it. It's the most important subject. Better if you know how to solve the problems manually.
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u/Total_Argument_9729 2d ago
Don’t expect to understand it. That’s all I can say. I’m a senior and mass transfer was the only thing I was like “fuck I don’t know what this is”. I mean I could solve some of the problems but I never really understood it at its core.
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u/Atonement-JSFT Pulp and Paper Process Control 2d ago
In - Out + Generation = Accumulation