{"id":497,"date":"2018-05-08T21:24:38","date_gmt":"2018-05-08T21:24:38","guid":{"rendered":"https:\/\/learn.hydrologystudio.com\/studio-express\/?post_type=ht_kb&#038;p=497"},"modified":"2022-01-28T17:07:06","modified_gmt":"2022-01-28T17:07:06","slug":"open-channels-pipes","status":"publish","type":"ht_kb","link":"https:\/\/learn.hydrologystudio.com\/studio-express\/knowledge-base\/open-channels-pipes\/","title":{"rendered":"Open Channels &#038; Pipes"},"content":{"rendered":"<p>Studio Express computes various parameters for a variety of channel and pipe shapes. In all cases, steady flow is assumed and thus normal depth is assumed. Manning\u2019s equation is used exclusively. When a known Q is specified it solves for the depth using an iterative procedure.<\/p>\n<p><strong>Manning&#8217;s Equation<\/strong><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-344\" src=\"https:\/\/learn.hydrologystudio.com\/culvert-studio\/wp-content\/uploads\/sites\/4\/2017\/10\/EqMannings.jpg\" alt=\"\" width=\"173\" height=\"60\" \/><\/p>\n<p>Where:<\/p>\n<p>Q = flow rate in cfs (cms)<br \/>\nn = roughness coefficient<br \/>\nA = cross-sectional area in sqft (sqm)<br \/>\nR = hydraulic radius = A \/ WP<br \/>\nS = channel slope in ft\/ft (m\/m)<br \/>\nKm = 1.49 (1.0)<\/p>\n<p><strong>Composite Manning\u2019s n<\/strong><br \/>\nWith user-defined sections that have varying n values, Studio Express uses the following Horton-Einstein equation to first compute a composite roughness coefficient. Then it employs Manning\u2019s equation as described above.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-311\" src=\"https:\/\/learn.hydrologystudio.com\/culvert-studio\/wp-content\/uploads\/sites\/4\/2017\/10\/EqCompNv.jpg\" alt=\"\" width=\"179\" height=\"131\" \/><\/p>\n<p>Where:<br \/>\nnc = composite n-value<br \/>\nPi = wetted perimeter of subdivision i<br \/>\nni = n-value for subdivision i<br \/>\np = total wetted perimeter of channel<\/p>\n<p><strong>Critical Depth<\/strong><br \/>\nYc, or critical depth is computed using the following equation along with an iterative procedure:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-345\" src=\"https:\/\/learn.hydrologystudio.com\/culvert-studio\/wp-content\/uploads\/sites\/4\/2017\/10\/EqCriticalDepth.jpg\" alt=\"\" width=\"120\" height=\"80\" \/><\/p>\n<p>Where:<\/p>\n<p>Q = flow rate<br \/>\nA = cross-sectional area<br \/>\nT = top width<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-349\" src=\"https:\/\/learn.hydrologystudio.com\/culvert-studio\/wp-content\/uploads\/sites\/4\/2017\/10\/TrapezoidalChannel-1.jpg\" alt=\"\" width=\"860\" height=\"391\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Studio Express computes various parameters for a variety of channel and pipe shapes. In all cases, steady flow is assumed and thus normal depth is assumed. Manning\u2019s equation is used exclusively. When a known Q is specified it solves for the depth using an iterative procedure. Manning&#8217;s Equation Where: Q&#8230;<\/p>\n","protected":false},"author":1,"comment_status":"closed","ping_status":"closed","template":"","format":"standard","meta":{"footnotes":""},"ht-kb-category":[31],"ht-kb-tag":[],"class_list":["post-497","ht_kb","type-ht_kb","status-publish","format-standard","hentry","ht_kb_category-computational-methods"],"_links":{"self":[{"href":"https:\/\/learn.hydrologystudio.com\/studio-express\/wp-json\/wp\/v2\/ht-kb\/497","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/learn.hydrologystudio.com\/studio-express\/wp-json\/wp\/v2\/ht-kb"}],"about":[{"href":"https:\/\/learn.hydrologystudio.com\/studio-express\/wp-json\/wp\/v2\/types\/ht_kb"}],"author":[{"embeddable":true,"href":"https:\/\/learn.hydrologystudio.com\/studio-express\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/learn.hydrologystudio.com\/studio-express\/wp-json\/wp\/v2\/comments?post=497"}],"version-history":[{"count":3,"href":"https:\/\/learn.hydrologystudio.com\/studio-express\/wp-json\/wp\/v2\/ht-kb\/497\/revisions"}],"predecessor-version":[{"id":851,"href":"https:\/\/learn.hydrologystudio.com\/studio-express\/wp-json\/wp\/v2\/ht-kb\/497\/revisions\/851"}],"wp:attachment":[{"href":"https:\/\/learn.hydrologystudio.com\/studio-express\/wp-json\/wp\/v2\/media?parent=497"}],"wp:term":[{"taxonomy":"ht_kb_category","embeddable":true,"href":"https:\/\/learn.hydrologystudio.com\/studio-express\/wp-json\/wp\/v2\/ht-kb-category?post=497"},{"taxonomy":"ht_kb_tag","embeddable":true,"href":"https:\/\/learn.hydrologystudio.com\/studio-express\/wp-json\/wp\/v2\/ht-kb-tag?post=497"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}