En \u00e9t\u00e9 la temp\u00e9rature ext\u00e9rieure et bien plus \u00e9lev\u00e9e que la temp\u00e9rature en sous-sol. Cela g\u00e9n\u00e8re des courants d’air avec dans certaines conditions de l’air frais qui sort de la cavit\u00e9.<\/p>\n
Pour en savoir plus sur les courants d\u2019air<\/a>.<\/span><\/span><\/p>\n Cet air \u00e9tant de temp\u00e9rature diff\u00e9rente qu’\u00e0 l’ext\u00e9rieure, l’id\u00e9e et de la d\u00e9tecter avec une cam\u00e9ra thermique. Attention ! La cam\u00e9ra thermique ne permet cependant pas de \u00ab voir \u00bb l\u2019air froid, mais seulement les objets refroidis par cet air. En effet, la densit\u00e9 de l\u2019air est trop faible pour \u00eatre observable directement. Plus la temp\u00e9rature ext\u00e9rieure est chaude, plus le contrast thermique avec l’air souterrain froid sera important. Ceci est \u00e0 privil\u00e9gier pour de bonnes images.<\/p>\n Des cam\u00e9ras thermiques \u00e0 un prix tr\u00e8s abordable, comme en particulier la FLIR ONE ou la SEEK CompactPRO, sont aujourd\u2019hui commercialis\u00e9es. Ces cam\u00e9ras se connectent sur le port USB de t\u00e9l\u00e9phones portables Andro\u00efd ou iOS. La cam\u00e9ra FLIR ONE a \u00e9t\u00e9 test\u00e9e avec succ\u00e8s. Ses points faibles sont la calibration et l’autonomie. Pour l’autonomie, il suffit de connecter la cam\u00e9ra \u00e0 une powerbank externe.<\/p>\nngg_shortcode_1_placeholder\n Les r\u00e9sultats obtenus sont fantastiques permettant une d\u00e9tectation facile des cavit\u00e9s qui ont un courant d’air sortant. La difficult\u00e9 principale concerne la calibration et l’\u00e9chelle de temp\u00e9rature, afin de mettre en \u00e9vidence les temp\u00e9ratures anormales provenant des cavit\u00e9s. Quelques images prisent aux Grottes aux F\u00e9es de Vallorbe et sur le lapiaz du Folliu. Les rivi\u00e8res d’air froid sont clairement visibles.<\/p>\n ngg_shortcode_2_placeholder En \u00e9t\u00e9 la temp\u00e9rature ext\u00e9rieure et bien plus \u00e9lev\u00e9e que la temp\u00e9rature en sous-sol. Cela g\u00e9n\u00e8re des courants d’air avec […]<\/p>\n","protected":false},"author":1,"featured_media":5169,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ngg_post_thumbnail":0,"footnotes":""},"categories":[53,80,2],"tags":[],"class_list":["post-5139","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-speleologie-technique","category-technique-speleologie","category-technique"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=\/wp\/v2\/posts\/5139","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=5139"}],"version-history":[{"count":3,"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=\/wp\/v2\/posts\/5139\/revisions"}],"predecessor-version":[{"id":5191,"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=\/wp\/v2\/posts\/5139\/revisions\/5191"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=\/wp\/v2\/media\/5169"}],"wp:attachment":[{"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5139"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5139"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.techt.ch\/mdemierre\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5139"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nngg_shortcode_0_placeholder<\/p>\n
\nUn outils suppl\u00e9mentaire pour la prospection !
\nPour en savoir plus sur la FLIR ONE<\/a><\/span> et la SEEK Compact PRO<\/a><\/span><\/span>.<\/p>\nngg_shortcode_3_placeholder\n","protected":false},"excerpt":{"rendered":"