{"id":3237,"date":"2014-06-07T12:07:54","date_gmt":"2014-06-07T11:07:54","guid":{"rendered":"https:\/\/www.ultraflux.net\/mesure-ecoulement-surface-libre-2\/"},"modified":"2023-03-23T09:20:26","modified_gmt":"2023-03-23T08:20:26","slug":"free-surface-flow-rate-measurement","status":"publish","type":"page","link":"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/","title":{"rendered":"Free surface flow rate measurement"},"content":{"rendered":"<ul class=\"gallery\"><li class=\"active image-1\"><p><img width=\"1000\" height=\"1000\" src=\"https:\/\/www.ultraflux.net\/wp-content\/uploads\/2014\/06\/Pont-Austerlitz-sonde-1000x1000.jpg\" class=\"attachment-large size-large\" alt=\"\" decoding=\"async\" loading=\"lazy\" srcset=\"https:\/\/www.ultraflux.net\/wp-content\/uploads\/2014\/06\/Pont-Austerlitz-sonde-1000x1000.jpg 1000w, https:\/\/www.ultraflux.net\/wp-content\/uploads\/2014\/06\/Pont-Austerlitz-sonde-1000x1000-150x150.jpg 150w, https:\/\/www.ultraflux.net\/wp-content\/uploads\/2014\/06\/Pont-Austerlitz-sonde-1000x1000-300x300.jpg 300w\" sizes=\"(max-width: 1000px) 100vw, 1000px\" \/><\/p><\/li><\/ul><nav id=\"gallery-nav\"><ul class=\"gallery-nav\"><li class=\"active image-1\"><p><\/p><\/li><\/ul><\/nav>\n<div class=\"block_enhanced\"><p>\nFree surface flow rate measurements are found using a combination of <strong>level measurements<\/strong>, <strong>speed measurements<\/strong> and <strong>channel shape<\/strong>. The flow rate is therefore obtained by combining the flow rates in each part of the wetted section.<\/p>\n<\/div>\n<div class=\"block\"><div class=\"title\">Composition of a measuring point<\/div><div class=\"text\"><div class=\"text-container\"><p>\nA measuring point consists of:<\/p>\n<ul>\n<li>1 converter,<\/li>\n<li>1-2 level sensors,<\/li>\n<li>1-8 speed measurement chords.<\/li>\n<\/ul>\n<p>The amount and position of the probes depends on:<\/p>\n<ul>\n<li>the height of the structure,<\/li>\n<li>the tide range,<\/li>\n<li>the specific features upstream and downstream of the site in question,<\/li>\n<li>the required precision.<\/li>\n<\/ul>\n<p>\n<\/div><\/div><\/div>\n<div class=\"block\"><div class=\"title\">Diagram illustrating the measurement principle<\/div><div class=\"text\"><div class=\"text-container\"><p>\n<img decoding=\"async\" class=\"\" src=\"https:\/\/www.ultraflux.net\/wp-content\/themes\/ufx\/img\/debitmetres-rivieres.png\" alt=\"\" \/><\/p>\n<\/div><\/div><\/div>\n<div class=\"block\"><div class=\"title\">Advantages of ultrasound transit time measurements<\/div><div class=\"text\"><div class=\"text-container\"><\/p>\n<p>Ultrasound measurements present several advantages for this type of application:<\/p>\n<ul>\n<li><strong>reliable process<\/strong> unaffected by the nature of the fluid and its temperature,<\/li>\n<li>highly <strong>dynamic measurements<\/strong>: good results at both low and high water levels,<\/li>\n<li>takes into account <strong>different velocity profiles<\/strong> (up to 8 chords),<\/li>\n<li>takes into account the <strong>entire section<\/strong> of the structure,<\/li>\n<li><strong>defines the section precisely<\/strong> using 20 points incorporating left and right width\/height,<\/li>\n<li>can be used to take measurements in <strong>very wide structures<\/strong> (200 m).<\/li>\n<\/ul>\n<p>\n<\/div><\/div><\/div>\n<div class=\"block_enhanced\"><p>\n<span style=\"font-size: 13px;\">This measurement principle can also be applied to <strong>partially filled pipes<\/strong>.<\/span><\/p>\n<\/div>\n<div class=\"block_enhanced\"><p>\n<span style=\"font-size: 13px;\"><em>Discover our <a title=\"Flowmeters \u2013 free surface flows\" href=\"https:\/\/www.ultraflux.net\/en\/products\/flowmeters-free-surface-flows\/\" target=\"_blank\" rel=\"noopener\">flow meters for channels and rivers<\/a>.<\/em><\/span><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":3,"featured_media":0,"parent":5588,"menu_order":10,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v21.1 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Free surface flow rate measurement | Ultraflux - flow meters<\/title>\n<meta name=\"description\" content=\"Discover ultrasonic free surface flow rate measurement (for rivers, channels or partially filled pipes). Find the best flow meter for your application.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Free surface flow rate measurement | Ultraflux - flow meters\" \/>\n<meta property=\"og:description\" content=\"Discover ultrasonic free surface flow rate measurement (for rivers, channels or partially filled pipes). Find the best flow meter for your application.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/\" \/>\n<meta property=\"og:site_name\" content=\"Ultraflux - Expert in flow meters\" \/>\n<meta property=\"article:modified_time\" content=\"2023-03-23T08:20:26+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.ultraflux.net\/wp-content\/themes\/ufx\/img\/debitmetres-rivieres.png\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/\",\"url\":\"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/\",\"name\":\"Free surface flow rate measurement | Ultraflux - flow meters\",\"isPartOf\":{\"@id\":\"https:\/\/www.ultraflux.net\/#website\"},\"datePublished\":\"2014-06-07T11:07:54+00:00\",\"dateModified\":\"2023-03-23T08:20:26+00:00\",\"description\":\"Discover ultrasonic free surface flow rate measurement (for rivers, channels or partially filled pipes). Find the best flow meter for your application.\",\"breadcrumb\":{\"@id\":\"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.ultraflux.net\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Expertise\",\"item\":\"https:\/\/www.ultraflux.net\/en\/expertise\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Free surface flow rate measurement\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.ultraflux.net\/#website\",\"url\":\"https:\/\/www.ultraflux.net\/\",\"name\":\"Ultraflux - Expert en d\u00e9bitm\u00e8tres\",\"description\":\"Ultrasonic flow meters and detectors\",\"publisher\":{\"@id\":\"https:\/\/www.ultraflux.net\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.ultraflux.net\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\/\/www.ultraflux.net\/#organization\",\"name\":\"Ultraflux\",\"url\":\"https:\/\/www.ultraflux.net\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.ultraflux.net\/#\/schema\/logo\/image\/\",\"url\":\"https:\/\/www.ultraflux.net\/wp-content\/uploads\/2015\/08\/UltrafluxLogoTypoPantone-e1439281649737.jpg\",\"contentUrl\":\"https:\/\/www.ultraflux.net\/wp-content\/uploads\/2015\/08\/UltrafluxLogoTypoPantone-e1439281649737.jpg\",\"width\":410,\"height\":77,\"caption\":\"Ultraflux\"},\"image\":{\"@id\":\"https:\/\/www.ultraflux.net\/#\/schema\/logo\/image\/\"},\"sameAs\":[\"https:\/\/www.linkedin.com\/company\/ultraflux?trk=company_logo\",\"https:\/\/www.youtube.com\/channel\/UC_VX6jlhzMxIMcx4B2e238A\"]}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Free surface flow rate measurement | Ultraflux - flow meters","description":"Discover ultrasonic free surface flow rate measurement (for rivers, channels or partially filled pipes). Find the best flow meter for your application.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/","og_locale":"en_US","og_type":"article","og_title":"Free surface flow rate measurement | Ultraflux - flow meters","og_description":"Discover ultrasonic free surface flow rate measurement (for rivers, channels or partially filled pipes). Find the best flow meter for your application.","og_url":"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/","og_site_name":"Ultraflux - Expert in flow meters","article_modified_time":"2023-03-23T08:20:26+00:00","og_image":[{"url":"https:\/\/www.ultraflux.net\/wp-content\/themes\/ufx\/img\/debitmetres-rivieres.png"}],"twitter_misc":{"Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/","url":"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/","name":"Free surface flow rate measurement | Ultraflux - flow meters","isPartOf":{"@id":"https:\/\/www.ultraflux.net\/#website"},"datePublished":"2014-06-07T11:07:54+00:00","dateModified":"2023-03-23T08:20:26+00:00","description":"Discover ultrasonic free surface flow rate measurement (for rivers, channels or partially filled pipes). Find the best flow meter for your application.","breadcrumb":{"@id":"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.ultraflux.net\/en\/expertise\/free-surface-flow-rate-measurement\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.ultraflux.net\/"},{"@type":"ListItem","position":2,"name":"Expertise","item":"https:\/\/www.ultraflux.net\/en\/expertise\/"},{"@type":"ListItem","position":3,"name":"Free surface flow rate measurement"}]},{"@type":"WebSite","@id":"https:\/\/www.ultraflux.net\/#website","url":"https:\/\/www.ultraflux.net\/","name":"Ultraflux - Expert en d\u00e9bitm\u00e8tres","description":"Ultrasonic flow meters and detectors","publisher":{"@id":"https:\/\/www.ultraflux.net\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.ultraflux.net\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/www.ultraflux.net\/#organization","name":"Ultraflux","url":"https:\/\/www.ultraflux.net\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.ultraflux.net\/#\/schema\/logo\/image\/","url":"https:\/\/www.ultraflux.net\/wp-content\/uploads\/2015\/08\/UltrafluxLogoTypoPantone-e1439281649737.jpg","contentUrl":"https:\/\/www.ultraflux.net\/wp-content\/uploads\/2015\/08\/UltrafluxLogoTypoPantone-e1439281649737.jpg","width":410,"height":77,"caption":"Ultraflux"},"image":{"@id":"https:\/\/www.ultraflux.net\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.linkedin.com\/company\/ultraflux?trk=company_logo","https:\/\/www.youtube.com\/channel\/UC_VX6jlhzMxIMcx4B2e238A"]}]}},"_links":{"self":[{"href":"https:\/\/www.ultraflux.net\/en\/wp-json\/wp\/v2\/pages\/3237"}],"collection":[{"href":"https:\/\/www.ultraflux.net\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.ultraflux.net\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.ultraflux.net\/en\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ultraflux.net\/en\/wp-json\/wp\/v2\/comments?post=3237"}],"version-history":[{"count":1,"href":"https:\/\/www.ultraflux.net\/en\/wp-json\/wp\/v2\/pages\/3237\/revisions"}],"predecessor-version":[{"id":11501,"href":"https:\/\/www.ultraflux.net\/en\/wp-json\/wp\/v2\/pages\/3237\/revisions\/11501"}],"up":[{"embeddable":true,"href":"https:\/\/www.ultraflux.net\/en\/wp-json\/wp\/v2\/pages\/5588"}],"wp:attachment":[{"href":"https:\/\/www.ultraflux.net\/en\/wp-json\/wp\/v2\/media?parent=3237"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}