Hydrogeology 101: Dupuit-Forchheimer equation
HTML-код
- Опубликовано: 15 окт 2024
- This video is about the Dupuit-Forchheimer equation which describes steady state flow to wells in unconfined aquifers. We will illustrate this equation with a practical example of a hypothetical well pumping in an irrigated area of the Kabul Basin, Afghanistan. We will derive the radius of influence of the well based on recharge rates estimated by the USGS 2010 study on the Kabul Basin. Then we will see the impact on the radius of influence if the irrigated area becomes urbanised and how this may affect our wellfield sustainability.
Link to Excel template on Google Drive: bit.ly/3utgp28
Please download to your computer and work on a copy.
Key references:
Mack, T.J. et al 2010, Conceptual model of water resources in the Kabul Basin, Afghanistan: U.S. Geological Survey Scientific Investigations Report 2009-5262, 240 p. Available online at pubs.usgs.gov/s...
E.G Böckh, 1971, Report on the Groundwater Resources of the City of Kabul
Dupuit, J. (1863). Etudes Théoriques et Pratiques sur le mouvement des Eaux dans les canaux découverts et à travers les terrains perméables (Second ed.). Paris: Dunod.
Forchheimer, P. (1886). "Über die Ergiebigkeit von Brunnen-Anlagen und Sickerschlitzen". Z. Architekt. Ing.-Ver. Hannover. 32: 539-563.
#Dupuit-Forchheimer #groundwaterrecharge #effectsof urbanisation
Great video. You explained the concepts much better than my professor could. Can you also share the excel template you used for Dupuit's example, similar to the one you shared for Thiem's equation?
Thanks for the reminder! Here is the link to Excel template on Google Drive: bit.ly/3utgp28
@@GeosearchInternational Thank you so much!
welcome! all the best, Andreas
Andreas, thank you very much for great explanation and visualisation! Practical cases and Excel program are also great!
Hi @Oleg Li, Glad you found them useful! All the best, Andreas
Thank you, sir, I am currently struggling to understand my professor on groundwater hydraulics and your videos really helps me understand his lecture more. kind regards from the UK. I am currently doing my Masters in Hydrogeology with not much background on Mechanics. Your videos motivate me to learn more.
You are most welcome Maria! I also did my MSc Hydrogeology in the UK at UCL many years ago & I was privileged to have a great teacher - Glyn Jones. He told me once that what is most important is not to be able to derive equations, but to know when to use them and what their limitations are. I think that is the secret to becoming a good hydrogeologist. You need to learn how to visualise groundwater flow - especially understand the water balance - and then know which tools to use. For visualisation we have so many new tools nowadays, not just complex modelling software. I'm especially interested in Excel because it is widely available - check out my other videos.
In 2013 I started teaching hydrogeology in Afghanistan, and it is the most difficult job I have ever done. Much harder than being a consultant to EU/WB/ADB... some people can visualise things using equations (maybe your prof?), but many - like myself - need to see it in 3D. It all depends on how your mind works, and that is another fascinating topic!
I wish you all the best with your studies & if you have any questions about my videos I will try to answer them. All the best, Andreas
@@GeosearchInternational Yes, my professor does explain hydraulics by deriving equations as he use to be a mathematician. I am also a visual learner like yourself so I particularly like seeing hydrogeology in 3D. p.s. I am doing mine at the University of Birmingham. Thank you Andreas, I will let you know if I have any questions.
Hi Maria, Good luck with your course & be patient. It takes many years to become good in hydrogeology & actually you never stop learning. All the best, Andreas
Thanks for this! I can't understand most of the technical details, but I'm grateful for a lot of the perspective you provided. One segment of intrigue I have now is I'm wondering what you meant by "young water"? I had been under the impression that all water was created at the same time. I'd love if you could shed some light on this. Thanks!
You're very welcome! The water we drink today is the same water the dinosaurs drank so it is not really young as the water cycle is a continuous process that has been going on for millions of years. For hydrogeologists "young groundwater" just means that it has been recharged not so long ago. e.g., if we find tritium (3H) in the groundwater, it must have been recharged from precipitation contaminated by the atomic explosions in the 1950s/early 1960s. Have a look at: pubs.usgs.gov/fs/FS-134-99/ All the best, Andreas
@@GeosearchInternational You answered so quickly, thank you! This information is greatly appreciated. (And super interesting!)
Welcome! All the best, Andreas
Thanks, got my homework done
You are welcome Xogen, All the best, Andreas
Thank you sir!
You are welcome!
congratulations u went tru all the vids
Welcome! All the best, Andreas
Thanks
You're welcome!
You're welcome!
Those decimal commas and points...
... and your point is?
@@GeosearchInternational You used commas as decimal and thousand separators, found it a bit confusing (with the 1km value). Didn't want to be overly critical as the channel is truly excellent.
Hi Nikola, you raise a very important point which is the confusion about commas and points. In most of the English-speaking world points are used for the decimal separators and commas for the thousands. This is what I have been using in the videos, though it may be better to go for a space between the thousands. So instead of r0 = 1,071m it should be 1 071m. The problem is that unless you use a hard space, it can split the number over two lines. I actually started my first two years of school using the non-anglophone system (commas instead of points for the decimal separator). Will try to stop the confusion in future videos. Thanks again & all the best, Andreas