Відео

Thank you for your kind words, it is greatly appreciated!

Yes, a cylinder can be generated through a similar means using the 3D shapes; we can look at producing a video tutorial on this for sure.

Yes, you are right, that was my mistake, thank you for noticing it and letting me know. I hope the overall idea still made sense. Thank you for your kind words and for watching!

Yes, the bubble column is a closed system, as are most bioreactors due to the cultivation duration. The schematics are just basic however, in more detailed ones you would find small relief vents, usually at the top to allow the air to escape, preventing an increase in pressure within the vessel. I hope this clears things up, and thanks for watching!

Yes, you are correct, some of the algebraic manipulations could have been done earlier; however, often, I find simplifying steps too quickly can be confusing for students who are just learning, but you are definitely right it could be done earlier! Thank you for watching it's much appreciated!

​@@TheChemEngStudent I recently retired from 21 years of higher education physics teaching and research. Although the research is theoretical and is continuing just as before... My PhD is in EEE, but I now find myself learning Chemical Engineering as part of the diverse skillset required for my new career managing employees who design heat exchangers and reactors. You videos have been far more helpful than the textbooks!

@@stevenverrall4527 Thank you for your very kind words, it is greatly appreciated! I am truly honoured that a distinguished highly experienced academic is finding value in my work. Full respect for learning Chemical Engineering, one of my specialisms is in Heat Transfer and heat exchanger design and optimisation. If you have any particular topic requests please just let me know and I can create a video.

This really depends on your background and what elements you find most difficult. I would say either taking additional mathematics courses/classes at university or seeking some tuition services. If you would like to get in touch with me, I can look at scheduling some support sessions as I also offer mentorship to some students if this would be of interest to you?

Thank you very much for your kind words and for subscribing, it is greatly appreciated! I'm glad you find the channel helpful, and if you ever need any additional information/advice, please don't hesitate to reach out!

Thank you for your kind words, its much appreciated! I understand your question as at the time I had the same one. This pressure drop as it is on a per meter basis is telling us the pressure/force the pump will push the fluid forward by every meter (the pump head would tell us how many meters this would be valid for). This relationship allows us to specify a distance to model around giving us the pressure drop from point 1 to point 2. There are lots of other correlations, this was the one I used in my design based on the information I had. I hope this helps and thanks for watching!

We can express this as kg/kmol which allows us to keep the same value since the conversion from g to kg would cancel the conversion of mol to kmol. I hope this helps, thanks for watching!

The value of 104 is the heat loss provided in the question description. The 4.2 is the conversion from kcal to kj and the 1/3600 is the conversion of hours to seconds. Thanks for watching and I hope this helps!

I have a Scottish accent

@@TheChemEngStudent yup i thought so, cuz its definitely not american nor aussie. and accentts like canadian, south african and new zealander tend to be clear and not too distinct like welsh, scottish and irish!

@@9LimaAlpha7 It is a distinct accent, to be more specific I have an Edinburgh Scottish accent. I hope it isn't too difficult to understand!

@@TheChemEngStudent no not at all, in fact its quite charming! i have lived in england for a few years and ive aquired a british accent (not as a native, but very fluent) hence, i dont struggle to understand different accents

We can certainly look at putting something together, great recommendation! You are definatley on to something, once you understand physics you have a different perspective on the world, and this would certainly benefit everyones pockets!

Thank you for your kind words Sir! Much appreciated!

We can make this assumption when we consider the overall balance that is to say that both n2 and n4 can be grouped to represent the "top product" leaving the entire system. This is only applicable for the overall, this wouldn't apply to the individual unit operations balance. I hope that makes sense and thank you for watching!

Thank you for watching, yes you are correct in that there is essentially a quasi-state occurring where the value would tend towards zero, however for ease of explanation for these tutorials we don't want to over confuse as in my experience as a lecturer, as soon as you enter the realm of quasi-systems all is lost. But you are absolutely correct and thank you very much for commenting on this!

As it is Non-Newtonian you need to identify a suitable model that you can extract the reliable physical properties from. Then we need to know the flow regime using Reynolds, identify the suitable shear stress formula. One to potentially use is... gamma = (4.Q/pi.r^3). The actual equations however will vary depending on the model used i.e. Bingham, Herschel-Bulkley, Cross, etc. I hope this helps, and thanks for watching!

@@TheChemEngStudent Any book reference that you recommend related to this subject ? Thank you

@@josegabrielhernandezaguirr5267 There are a lot of great books on this, I have attached a copy of our course descriptor which gives you a list of the books used for making this content. I hope this helps. If you need anything else please just get in touch! www.chemengstudent.com/wp-content/uploads/2024/06/Fluid-Dynamics-Mechanics-Course-Descriptor.pdf

We are currently updating the library and hope to have it fully up and running in the coming months. I will comment the link when its ready!

@@TheChemEngStudent thank you !

That's a really interesting question! The key linkage here is in the use of Grashof number as the Rayleigh number is equal to multiplication of Prandtl and Grashof. Prandtl explains the thermal diffusivity whereas Grashof explains the buoyancy and viscosity. These combined can then be approximated to Nusselt number which explains the heat transfer effects. There are numerous correlations based on flow type, and geometric confinement. I hope this helps, thank you for watching!

Thank you for your kind words, much appreciated!

Thank you for your kind words, much appreciated!

Thank you for your very kind words, it is greatly appreciated! Glad you found the video helpful!

Yes since we have a binary mixture the data is inherantly known; if there was more than two species then this might not be valid; however in this case you are correct! A good book I have used in the past is "Process Modelling & Simulation in Chemical, Biochemical & Environmental Engineering", this is a link for your reference. Thank you for watching and I hope this helps! amzn.to/3XOLTC1

Absolutely correct! Thank you very much for watching and commenting, it is much appreciated!

Thank you for your kind words, much appreciated.

I'm sorry you feel that way, however I am not sure I understand what you mean. As I am sure you are aware the nomenclature for carrying out these balances can vary, and so this is my preferred method. In regard to the temperature points I don't fully know why you mean as following the systematic process it does make sense. I would ask you to please reframe from derogative statements on this channel. If you would like to discuss things further, please do send me an email and I would be happy to speak further on this.

@@TheChemEngStudent In What temperature is your ΔΗrxn. It is a simple question. Your systematic process is just copy paste.

The number of knowns can be extracted directly from the question, however, as this is a binary system we can use this to our advantage since if we know the mole fraction of species A then we know the mole fraction of species B would be 1- A. I hope this helps, and thanks for watching!

Thank you for your kind words! In the second example, with the overall balance there is three knowns, it might be because it has been written as "2 balances, n2 = n4" this means 2 balances and 1 relationship between the top products i.e. a total of 3 knowns. I hope this helps, and thanks again for watching!

Thank you for your kind words, much appreciated, wishing you all the best for your PhD!

Thank you for your kind words, much appreciated!

Thank you for watching and for your feedback, much appreciated!

Thank you for your kind words! Typically within the design stage we can decide upon the reflux ratio prior to the design. If our target values aren't met then we can revise. It's usually best to go for a reflux of 1 as an initial guess, unless you have other information based on product quaility/purity. I hope this helps!

Thank you for watching, and for your kind words, much appreciated!

Thanks for watching! Much appreciated!

Thank you for your feedback, I understand what you are referring to, however in this case the X term is indicative of biomass weight and not as a concentration. A similar empirical equation can be used to deduce the relative concentration, but in this case, it is simply the weight of biomass. But certainly, if you would like to discuss further, please do get in touch. Thanks again for watching, much appreciated!

Thank you for your kind words and for subscribing, much appreciated! Yes, Umax can be determined experimentally since you will monitor the growth periodically, you can deduce at which point the maximum growth rate occurs. Bioreactors typically don't run in continuous systems given there is a prolonged period required, unless the organisms are pre-cultivated beforehand to the design would be the same. Some variation occurs when using heterotrophic systems such as fermenters. This point really depends upon what variables/factors you intend on varying to establish if there are correlations between say nutrient concentration and growth rate. These would need to be carried out experimentally. Typically, from my experience different organisms will respond differently to nutrient starvation or surplus and so it is highly dependent upon the organism as well. I will be releasing more videos soon on other types of bioreactors so we can add in continuous systems for you certainly! I hope I have answered all your questions.

Thank you for your comment. In Grashoff No. there is no density term if the kinematic viscosity is used which shouldn't be represented by Mu thank you for spotting this, in this particular version it should be upsilon for the kinematic viscosity. Much appreciated for your feedback!

Yes the Rho(b) is the density of the bed.