{"id":86,"date":"2019-11-27T15:25:03","date_gmt":"2019-11-27T15:25:03","guid":{"rendered":"http:\/\/aquifer.geology.buffalo.edu\/?p=86"},"modified":"2020-06-03T18:24:00","modified_gmt":"2020-06-03T18:24:00","slug":"darcys-law-and-radial-coordinates","status":"publish","type":"post","link":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/2019\/11\/27\/darcys-law-and-radial-coordinates\/","title":{"rendered":"Darcy\u2019s Law and Radial Coordinates"},"content":{"rendered":"\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1024\" src=\"http:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Radial_Two_models-1024x1024.jpg\" alt=\"\" class=\"wp-image-161\" srcset=\"https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Radial_Two_models-1024x1024.jpg 1024w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Radial_Two_models-150x150.jpg 150w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Radial_Two_models-300x300.jpg 300w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Radial_Two_models-768x768.jpg 768w\" sizes=\"auto, (max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><\/figure>\n\n\n\n<p>Objectives: Examine how Darcy\u2019s law changes when\ntransitioning to radial coordinates.<\/p>\n\n\n\n<p>1. When a well is being pumped in a homogenous aquifer it is a lot easier to quantify drawdown at a given distance away from the well using radial coordinates.&nbsp; This is because draw down away from the well is the same at any distance r<sub>x<\/sub> away from the well.&nbsp; As a result, when dealing with a well that is being pumped we need to modify Darcy\u2019s law from cartesian coordinates to radial coordinate (see equations below).&nbsp; In the following problem we are going to assume that well A is a pumping well that has been pumping for a long time.&nbsp; As a result, the water level is not changing with time and we can consider this a steady state problem.&nbsp; The water levels in well A and B are given in the table below.&nbsp; We are going to assume that the wells have a radius of 10 cm. Using the foldable aquifer model address the following problems.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"488\" src=\"http:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Screen-Shot-2019-11-27-at-10.24.38-AM-1024x488.png\" alt=\"\" class=\"wp-image-87\" srcset=\"https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Screen-Shot-2019-11-27-at-10.24.38-AM-1024x488.png 1024w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Screen-Shot-2019-11-27-at-10.24.38-AM-300x143.png 300w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Screen-Shot-2019-11-27-at-10.24.38-AM-768x366.png 768w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Screen-Shot-2019-11-27-at-10.24.38-AM.png 1070w\" sizes=\"auto, (max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"\"><tbody><tr><td>\n  <strong>Well <\/strong>\n  <\/td><td>\n  <strong>Water Level (m)<\/strong>\n  <\/td><\/tr><tr><td>\n  <strong>Well A<\/strong>\n  <\/td><td>\n  385\n  <\/td><\/tr><tr><td>\n  <strong>Well B<\/strong>\n  <\/td><td>\n  395\n  <\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p>A. Quantify the hydraulic gradient between well A and well\nB. &nbsp;&nbsp;<\/p>\n\n\n\n<p>B. Describe what the area term in Darcy\u2019s law represents in the problem below, considering water is flowing between well A and well B.&nbsp;&nbsp; &nbsp;<\/p>\n\n\n\n<p>C.&nbsp; Determine the\npumping rate in m<sup>3<\/sup>\/day that is necessary at well A to produce the\ndrawdown described above.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"782\" src=\"http:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2020\/06\/Radial_Pumping-Well-1024x782.png\" alt=\"\" class=\"wp-image-342\" srcset=\"https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2020\/06\/Radial_Pumping-Well-1024x782.png 1024w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2020\/06\/Radial_Pumping-Well-300x229.png 300w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2020\/06\/Radial_Pumping-Well-768x587.png 768w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2020\/06\/Radial_Pumping-Well-1536x1173.png 1536w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2020\/06\/Radial_Pumping-Well-2048x1564.png 2048w\" sizes=\"auto, (max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><\/figure>\n\n\n\n<div class=\"wp-block-file\"><a href=\"http:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2020\/06\/Radial_Pumping-Well.pdf\">Radial_Pumping Well<\/a><a href=\"http:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2020\/06\/Radial_Pumping-Well.pdf\" class=\"wp-block-file__button\" download>Download<\/a><\/div>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"616\" height=\"722\" src=\"http:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Radial_Pumping_Well_Page2.png\" alt=\"\" class=\"wp-image-134\" srcset=\"https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Radial_Pumping_Well_Page2.png 616w, https:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Radial_Pumping_Well_Page2-256x300.png 256w\" sizes=\"auto, (max-width: 616px) 100vw, 616px\" \/><\/figure>\n\n\n\n<div class=\"wp-block-file\"><a href=\"http:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Radial_Pumping_Well_Page2.pdf\">Foldable Aquifer Model Page 2<\/a><a href=\"http:\/\/aquifer.geology.buffalo.edu\/wp-content\/uploads\/2019\/11\/Radial_Pumping_Well_Page2.pdf\" class=\"wp-block-file__button\" download>Download<\/a><\/div>\n\n\n\n<figure class=\"wp-block-image\"><a href=\"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\"><img decoding=\"async\" src=\"https:\/\/i.creativecommons.org\/l\/by-nc\/4.0\/88x31.png\" alt=\"Creative Commons License\"\/><\/a><\/figure>\n\n\n\n<p><br>This work is licensed under a <a href=\"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">Creative Commons Attribution-NonCommercial 4.0 International License<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Objectives: Examine how Darcy\u2019s law changes when transitioning to radial coordinates. 1. When a well is being pumped in a homogenous aquifer it is a lot easier to quantify drawdown at a given distance away from the well using radial coordinates.&nbsp; This is because draw down away from the well is the same at any &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/aquifer.geology.buffalo.edu\/index.php\/2019\/11\/27\/darcys-law-and-radial-coordinates\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Darcy\u2019s Law and Radial Coordinates&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-86","post","type-post","status-publish","format-standard","hentry","category-darcys-law"],"_links":{"self":[{"href":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/wp-json\/wp\/v2\/posts\/86","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/wp-json\/wp\/v2\/comments?post=86"}],"version-history":[{"count":12,"href":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/wp-json\/wp\/v2\/posts\/86\/revisions"}],"predecessor-version":[{"id":343,"href":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/wp-json\/wp\/v2\/posts\/86\/revisions\/343"}],"wp:attachment":[{"href":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/wp-json\/wp\/v2\/media?parent=86"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/wp-json\/wp\/v2\/categories?post=86"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/aquifer.geology.buffalo.edu\/index.php\/wp-json\/wp\/v2\/tags?post=86"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}