{"id":335,"date":"2012-08-26T08:41:05","date_gmt":"2012-08-26T08:41:05","guid":{"rendered":"\/?page_id=335"},"modified":"2020-07-09T14:59:23","modified_gmt":"2020-07-09T12:59:23","slug":"aeronautics","status":"publish","type":"page","link":"https:\/\/www.lemma-ing.com\/?page_id=335","title":{"rendered":"Aeronautics applications"},"content":{"rendered":"<p style=\"text-align: justify;\">Since its creation LEMMA has been addressing the aeronautics industry by providing numerical solutions using its Fluid Structure Interaction capabilities, the intelligent mesh and optimal design algorithms.<\/p>\n<div><div class=\"su-accordion su-u-trim\"><\/div>\n<div class=\"su-spoiler su-spoiler-style-fancy su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\" data-anchor-in-url=\"no\"><div class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Intelligent mesh<\/div><div class=\"su-spoiler-content su-u-clearfix su-u-trim\">\n<ul>\n<li><strong>Turbopump application<span style=\"color: #000000;\">&nbsp;<\/span><\/strong><\/li>\n<\/ul>\n<div style=\"text-align: justify;\"><span style=\"color: #000000;\">With the new mesh technology based on edge swapping, no need to remesh during the simulation or to handle complex mesh movements. Fast and accurate, dedicated to all your rotating geometries !<\/span><\/div>\n<div>\n<p style=\"text-align: center;\"><iframe loading=\"lazy\" src=\"https:\/\/www.youtube-nocookie.com\/embed\/Q1SEhu-hTj0\" allow=\"accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen=\"\" width=\"560\" height=\"315\" frameborder=\"0\"><\/iframe><\/p>\n<ul>\n<li>&nbsp;<span style=\"color: #000000;\"><strong>Sonic bang prediction &amp; reduction<\/strong>&nbsp;: <strong>goal oriented steady meshing<\/strong><\/span><\/li>\n<\/ul>\n<div style=\"text-align: justify;\"><span style=\"color: #000000;\">While flying at supersonic speed, aerodynamic pressure perturbations produced by the aircraft in the close vicinity will propagate through the atmosphere down to the ground, leading to a sonic-boom. One of the challenges to be overcome to ensure the economical viability of a future supersonic civil transport is certainly the capability to fly supersonically overland. This capability will require that the aircraft generates an &#8220;acceptable&#8221; sonic boom, meaning a sonic boom which produces, at ground level, no (or sufficiently reduced) annoyance to humans and animals. The accurate modelling and prediction of the ground sonic boom signature is therefore a key-point for the design of a new civil transport supersonic aircraft and its future certification.&nbsp;<\/span><\/div>\n<div style=\"text-align: center;\"><iframe loading=\"lazy\" src=\"https:\/\/www.youtube-nocookie.com\/embed\/hW8-0pkECHg\" allowfullscreen=\"allowfullscreen\" width=\"560\" height=\"315\" frameborder=\"0\"><\/iframe><\/div>\n<\/div>\n<div style=\"text-align: center;\"><\/div>\n<div class=\"su-row\">\n<div class=\"su-column su-column-size-1-2\"><div class=\"su-column-inner su-u-clearfix su-u-trim\">\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-mesh-shock.png\" width=\"350\"><\/p>\n<p><center><strong>3D shock around a supersonic fighter jet.<\/strong><\/center><\/p>\n<\/div><\/div>\n<div class=\"su-column su-column-size-1-2\"><div class=\"su-column-inner su-u-clearfix su-u-trim\">\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-mesh-anisotropic.png\" width=\"350\"><\/p>\n<p><center><strong>3D anisotropic mesh.<\/strong><\/center><\/p>\n<\/div><\/div>\n<\/div>\n<div class=\"su-row\">\n<div class=\"su-column su-column-size-1-2\"><div class=\"su-column-inner su-u-clearfix su-u-trim\">\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-mesh-workflow.png\" width=\"500\"><\/p>\n<p><center><strong>Simulation workflow.<\/strong><\/center><\/p>\n<\/div><\/div>\n<div class=\"su-column su-column-size-1-2\"><div class=\"su-column-inner su-u-clearfix su-u-trim\">\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-mesh-pressure.png\" width=\"400\"><\/p>\n<p><center><strong>CFD-experiment pressure results comparison.<\/strong><\/center><\/p>\n<\/div><\/div>\n<\/div>\n<ul>\n<li><strong>High-Fidelity prediction of wing-tip vortices by adjoint mesh adaptation<\/strong><\/li>\n<\/ul>\n<div style=\"text-align: justify;\">In this example, we study the accurate prediction of wing tip vortices at large distance in the wake for transsonic flow conditions. The jet is flying at transonic cruise speed with Mach number 0.8 and an angle of attack of 3 degrees. The computational domain is a <strong>cylinder of radius 250 m and of length 700 m<\/strong>. The adjoint-based adaptation is based on the vorticity functional.<\/div>\n<div>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-mesh-falcon.png\" width=\"550\"><\/p>\n<p><center><strong>Left : pressure calculated in the wake. Right : anisotropic mesh adaptation.<\/strong><\/center><\/p>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-mesh-falcon-top.png\" width=\"450\"><\/p>\n<p><center><strong>Adjoint based anisotropic mesh generation.<\/strong><\/center><\/p>\n<ul>\n<li><strong>Automatic boundary layer generation<\/strong><\/li>\n<\/ul>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-mesh-falcon-layer.png\" width=\"550\"><\/p>\n<p><center><strong>Falcon jet with structured boundary layer mesh.<\/strong><\/center><\/p>\n<p class=\"thescrollup\"><a href=\"#top\"><img decoding=\"async\" src=\"https:\/\/www.lemma-ing.com\/wp-content\/plugins\/scrollup\/arrow.png\" alt=\"&#9660; Sommet\" title=\"&#9660; Sommet\" \/><\/a><\/p>\n<\/div><\/div>\n<\/div>\n<div class=\"su-spoiler su-spoiler-style-fancy su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\" data-anchor-in-url=\"no\"><div class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Fluid structure interaction &amp; aeroelasticity<\/div><div class=\"su-spoiler-content su-u-clearfix su-u-trim\">\n<p>The aims of the first study presented here were<\/p>\n<ul>\n<li>to predict the deformed shaped of AGARD wing, under supersonic flow,<\/li>\n<li>to provide an optimal shape to reduce sonic boom, coupled with aeroelasticity simulations.<\/li>\n<\/ul>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-fluid-wing.png\" width=\"450\"><\/p>\n<p><center><strong>3D deformed wing. Colored contours : mach number.<\/strong><\/center><\/p>\n<p>The second study presented below consists in predicting reverse thrust effects on induced forced vibrations caused by unsteady flow and&nbsp;large eddies detachments.<\/p>\n<div class=\"su-row\">\n<div class=\"su-column su-column-size-1-2\"><div class=\"su-column-inner su-u-clearfix su-u-trim\">\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-fluid-thrust.png\" width=\"380\"><\/p>\n<p><center><strong>Reverse thrust : a picture.<\/strong><\/center><\/p>\n<\/div><\/div>\n<div class=\"su-column su-column-size-1-2\"><div class=\"su-column-inner su-u-clearfix su-u-trim\">\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-fluid-geometry.png\" width=\"380\"><\/p>\n<p><center><strong>Reverse thrust : geometry and flow path.<\/strong><\/center><\/p>\n<\/div><\/div>\n<\/div>\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-fluid-flow.png\" width=\"380\"><\/p>\n<p><center><strong>Reverse thrust : snapshot of transient flow pattern.<\/strong><\/center><\/p>\n<p class=\"thescrollup\"><a href=\"#top\"><img decoding=\"async\" src=\"https:\/\/www.lemma-ing.com\/wp-content\/plugins\/scrollup\/arrow.png\" alt=\"&#9660; Sommet\" title=\"&#9660; Sommet\" \/><\/a><\/p>\n<\/div><\/div>\n<div class=\"su-spoiler su-spoiler-style-fancy su-spoiler-icon-plus su-spoiler-closed\" data-scroll-offset=\"0\" data-anchor-in-url=\"no\"><div class=\"su-spoiler-title\" tabindex=\"0\" role=\"button\"><span class=\"su-spoiler-icon\"><\/span>Shape optimisation<\/div><div class=\"su-spoiler-content su-u-clearfix su-u-trim\">\n<p>LEMMA can also provide powerfull shape optimization tools, based on adjoint optimization technic. Other numerical methods based on genetic and response surface algorithms, coupled to FFD (Free Form Deformation) shape deformation have also been developed.<\/p>\n<div class=\"su-row\">\n<div class=\"su-column su-column-size-1-2\"><div class=\"su-column-inner su-u-clearfix su-u-trim\">\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-shape-naca.png\" width=\"380\"><\/p>\n<p><center><strong>2D shape optimization of a NACA for drag reduction.<\/strong><\/center><\/p>\n<\/div><\/div>\n<div class=\"su-column su-column-size-1-2\"><div class=\"su-column-inner su-u-clearfix su-u-trim\">\n<p><img decoding=\"async\" class=\"aligncenter\" src=\"\/wp-content\/uploads\/Aero-shape-submarine.png\" width=\"380\"><\/p>\n<p><center><strong>3D shape optimization of aircraft engine pylons. Overpressure is considerably reduced by shape optimization.<\/strong><\/center><\/p>\n<\/div><\/div>\n<\/div>\n<\/div><\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Since its creation LEMMA has been addressing the aeronautics industry by providing numerical solutions using its Fluid Structure Interaction capabilities, the intelligent mesh and optimal design algorithms.<\/p>\n","protected":false},"author":229,"featured_media":0,"parent":66,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"full-width.php","meta":{"footnotes":""},"class_list":["post-335","page","type-page","status-publish","hentry"],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.lemma-ing.com\/index.php?rest_route=\/wp\/v2\/pages\/335","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lemma-ing.com\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.lemma-ing.com\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.lemma-ing.com\/index.php?rest_route=\/wp\/v2\/users\/229"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lemma-ing.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=335"}],"version-history":[{"count":172,"href":"https:\/\/www.lemma-ing.com\/index.php?rest_route=\/wp\/v2\/pages\/335\/revisions"}],"predecessor-version":[{"id":2766,"href":"https:\/\/www.lemma-ing.com\/index.php?rest_route=\/wp\/v2\/pages\/335\/revisions\/2766"}],"up":[{"embeddable":true,"href":"https:\/\/www.lemma-ing.com\/index.php?rest_route=\/wp\/v2\/pages\/66"}],"wp:attachment":[{"href":"https:\/\/www.lemma-ing.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=335"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}