Questions tagged [mass-transfer]
The mass-transfer tag has no usage guidance.
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what is effect of temperature on dew point?
I read that relative humidity changes with change in temperature though there can be constant humidity. So, if RH is changing then dew point should get increase with increase in temperature?
https://...
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Notation on Continuity Eqn Derivation
Was reviewing some notes on fluid dynamics, and the notes go as follows (conservation of mass for a qubic CV),
$$\frac{dm_{out}}{dt} = \rho u (dydz)_{x+dx} + \rho v (dxdz)_{y+dy} + (similarly,forZ) = \...
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How is the relationship between Entrance Length and Reynold’s number proven?
For laminar flow in a pipe or annulus of diameter $D$, there is a region from the circle of entry where velocity profile slowly develops until it is fully developed and no longer changes with the ...
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Under what conditions is grinding unnecessary for liquid-solid leaching in mineral processing?
I am a chemical engineering student and I am having trouble understanding a passage in a separation process textbook I am reading. The passage is about the preparing solids for leaching, such as ...
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Why do we consider the normal component of velocity in a flux and not the original direction of velocity?
Below is the equation of convective flux of an arbitrary property that is carried by particles. When particles move they carry their property along with them. Given a fixed surface in space, in order ...
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How to create a mechanical equivalent to dropping object onto steel floor
(I was informed on the Physics board that this is an Engineering question, therefore they closed it there, and I moved it here)
First, I have next to zero formal physics training... I opted for all ...
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How to calculate heat and mass transfer rates from an enclosed box?
I'd like to know if it's possible to calculate the heat and mass transfer rates from a small volume to the environment.
Let's assume there is a box with a small opening at the top. The air inside the ...
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Slow integration of system ODE under specific conditions in adsorption problem
I am trying to solve the system of ODEs below. I am applying the finite differences to z, so I get a system of ODE that I can solve with a solver like ode45.
The problem is that under the conditions ...
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Solving a linear mass balance equation in the form of Ax = 0 with variables in vector x
I have been tasked with solving a series of linear equations in the form of Ax = b, where b is the zero vector. Specifically, I have a matrix E which is 4x7 and a column vector r which is 7x1, as ...
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When teaching separation processes, which one should be introduced first? Distillation or absorption?
I am preparing a basic course on Separation Processes (5th semester, BSc Chemical Engineering). I can see that many well-known textbooks (e.g. Seader & Henley, Wankat) start by teaching in detail ...
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Does a tank of liquid nitrogen increase in total internal energy after emptying?
Suppose there's a 10 liter perfectly-insulated sealed tank of saturated liquid nitrogen at 4 bar. Therefore the fluid has properties,
$\rho=740 \,\frac{\text{kg}}{\text{m}^3}$,
$m=7.4 \,\text{kg}$,
$\...
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Modelling gas desorption from a still solution (e.g. a beer)
The common way to model or estimate gas (e.g. CO2) desorption rate from a liquid solution is by using an equation similar to this one
$J_{CO_2} = -k_L a(H·C^G_{CO_2} - C^L_{CO_2})$
where $J_{CO_2}$ ...
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Adsorption - what models are used for dry scrubbing?
For scrubbing with activated carbon, air is generally brought through a dry adsorption media, where the contaminant is adsorbed onto the media.
I would like to know what mathematical model is used ...
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