[{"data":1,"prerenderedAt":105},["ShallowReactive",2],{"WF2y8MavJScxJXZzdtLXy2hvuQDGsac5ZwBE4iPZ5jw":3,"_apollo:default":103,"_apollo:identified":104},{"seo":4,"posts":15},{"social":5,"openGraph":11,"__typename":14},{"twitter":6,"__typename":10},{"cardType":7,"username":8,"__typename":9},"summary_large_image","dassault3ds","SEOSocialTwitter","SEOSocial",{"defaultImage":12,"__typename":13},null,"SEOOpenGraph","SEOConfig",{"nodes":16,"__typename":102},[17],{"id":18,"slug":19,"title":20,"uri":21,"excerpt":22,"locale":23,"featuredImage":26,"tableOfContents":34,"content":35,"date":36,"translations":37,"author":38,"tags":51,"globalTags":65,"brands":73,"keywords":84,"seo":90,"__typename":101},"cG9zdDozMDI1MzU=","beyond-center-flight-envelope-lbm-fluid-simulations-defense-industry","Beyond the Center of the Flight Envelope: LBM-based Fluid Simulations for the Defense Industry","/brands/simulia/beyond-center-flight-envelope-lbm-fluid-simulations-defense-industry","\u003Cp>From supersonic cavity acoustics to multi-physics drone optimization, how PowerFLOW addresses the simulation challenges unique to military aircraft — and why the extreme requirements of the defense industry make it an ideal fit for LBM.\u003C/p>\n",{"locale":24,"__typename":25},"en_US","Locale",{"node":27,"__typename":33},{"large":28,"__typename":29,"medium_large":28,"thumbnail":30,"srcSet":31,"sizes":32},"https://blog-assets.3ds.com/uploads/2026/05/cover_image-new.png","MediaItem","https://blog-assets.3ds.com/uploads/2026/05/cover_image-new-150x150.png","https://blog-assets.3ds.com/uploads/2026/05/cover_image-new-300x82.png 300w, https://blog-assets.3ds.com/uploads/2026/05/cover_image-new.png 580w","(max-width: 300px) 100vw, 300px","NodeWithFeaturedImageToMediaItemConnectionEdge",[],"\n\u003Cp>Military aircraft inhabit a different aerodynamic world from their commercial counterparts. A fighter aircraft must perform reliably at extreme angles of attack, with asymmetric external stores and internal weapons bay doors that open and close in flight. Each condition presents simulation challenges that conventional RANS-based CFD handles poorly — and that LBM-based \u003Ca href=\"https://www.3ds.com/products/simulia/powerflow\">PowerFLOW\u003C/a> is particularly well-equipped to address.\u003C/p>\n\n\n\n\u003Ch3 class=\"wp-block-heading\" id=\"h-a-wider-harder-flight-envelope\">\u003Cstrong>A Wider, Harder Flight Envelope\u003C/strong>\u003C/h3>\n\n\n\n\u003Cp>The expanded flight envelope of defense aircraft spans low subsonic to Mach 2 and beyond, at angles of attack far exceeding those of commercial operations. At high angles of attack, leading-edge vortex breakdown governs stability in ways RANS cannot reliably predict. Inlet aerodynamics at transonic and supersonic conditions involves oblique shock systems and shock-boundary-layer interactions that are strongly unsteady and sensitive to small geometric details. PowerFLOW’s inherently time-accurate solvers — covering low subsonic Mach numbers to approximately 2.0 — address these complex conditions that determine structural fatigue and flight control dynamics [1].\u003C/p>\n\n\n\n\u003Ch3 class=\"wp-block-heading\" id=\"h-appendages-external-stores-and-weapons-bay-cavity-acoustics\">\u003Cstrong>Appendages, External Stores, and Weapons Bay Cavity Acoustics\u003C/strong>\u003C/h3>\n\n\n\n\u003Cp>Combat aircraft routinely fly with pylons carrying fuel tanks, targeting pods, and weapons in asymmetric combinations that change mission to mission. The aerodynamic impact of these appendages – turbulent wakes, shock impingement and buffeting loads on neighboring surfaces – must be understood not just at cruise but through the full carriage and release envelope, including the transient loads as payloads separate. PowerFLOW’s automatic Cartesian meshing eliminates the need to manually rebuild the computational grid for each new stores configuration — a task requiring weeks of manual effort in a traditional CFD workflow — making it practical to evaluate the full range of configurations a program must certify for.\u003C/p>\n\n\n\n\u003Cfigure class=\"wp-block-image size-full\">\u003Cimg loading=\"lazy\" decoding=\"async\" width=\"891\" height=\"244\" src=\"https://blog-assets.3ds.com/uploads/2026/05/pressure_fluctuations.png\" alt=\"\" class=\"wp-image-302537\" srcset=\"https://blog-assets.3ds.com/uploads/2026/05/pressure_fluctuations.png 891w, https://blog-assets.3ds.com/uploads/2026/05/pressure_fluctuations-300x82.png 300w, https://blog-assets.3ds.com/uploads/2026/05/pressure_fluctuations-768x210.png 768w\" sizes=\"auto, (max-width: 891px) 100vw, 891px\" />\u003Cfigcaption class=\"wp-element-caption\">\u003Cstrong>Simulation of unsteady pressure fluctuations in a weapons bay cavity.\u003C/strong>\u003C/figcaption>\u003C/figure>\n\n\n\n\u003Cp>\u003C/p>\n\n\n\n\u003Cp>Weapon bay cavities are another difficult aerodynamic challenge: they become acoustic resonators when opened in flight, generating intense pressure fluctuations. PowerFLOW directly resolves the full spectral content of these fluctuations, including tonal peaks and broadband background without the acoustic analogies that RANS-based approaches require [2].\u003C/p>\n\n\n\n\u003Ch3 class=\"wp-block-heading\" id=\"h-adding-vibroacoustics-to-the-simulation-toolkit\">\u003Cstrong>Adding Vibroacoustics to the Simulation Toolkit\u003C/strong>\u003C/h3>\n\n\n\n\u003Cp>Analyzing and improving the unsteady flow characteristics of military aircraft is only one of the benefits of an LBM-based CFD tool like PowerFLOW. Understanding the impact of aerodynamic fluctuations on vibrations of electronic components and structural fatigue can be equally or even more important. PowerFLOW achieves this by coupling to another tool in the \u003Ca href=\"https://www.3ds.com/products/simulia\">SIMULIA\u003C/a> arsenal – \u003Ca href=\"https://www.3ds.com/products/simulia/wave6\">Wave6\u003C/a> for vibroacoustic analysis. Pressure fluctuations on weapon payloads, cavities, radomes etc. are transferred to Wave6 to assess the vibration loads sensitive components have to withstand throughout the entire flight envelope. In the words of one of our customers: “Reducing flight events and developing accurate environments earlier in a program leads to (…) acceleration of the airworthiness certification process and platform integration” [3].\u003C/p>\n\n\n\n\u003Ch3 class=\"wp-block-heading\" id=\"h-rotorcraft-and-rotor-drone-aerodynamics\">\u003Cstrong>Rotorcraft and Rotor-drone Aerodynamics\u003C/strong>\u003C/h3>\n\n\n\n\u003Cp>Military helicopters and rotary-wing drones present some of the most intricate unsteady aerodynamic problems in defense engineering. Blade vortex interaction (BVI) and tail rotor shake  produce  impulsive noise and vibratory loads that drive both acoustic detectability and airframe fatigue. \u003C/p>\n\n\n\n\u003Cfigure class=\"wp-block-image size-full\">\u003Cimg loading=\"lazy\" decoding=\"async\" width=\"365\" height=\"145\" src=\"https://blog-assets.3ds.com/uploads/2026/05/rotorcraft.png\" alt=\"\" class=\"wp-image-302538\" srcset=\"https://blog-assets.3ds.com/uploads/2026/05/rotorcraft.png 365w, https://blog-assets.3ds.com/uploads/2026/05/rotorcraft-300x119.png 300w\" sizes=\"auto, (max-width: 365px) 100vw, 365px\" />\u003Cfigcaption class=\"wp-element-caption\">\u003Cstrong>Rotorcraft aerodynamics are highly complex and inherently transient.\u003C/strong>\u003C/figcaption>\u003C/figure>\n\n\n\n\u003Cp>\u003C/p>\n\n\n\n\u003Cp>In multi-rotor drone configurations, equivalent inter-rotor wake interactions occur at every blade passage. These phenomena are inherently transient and spatially complex, demanding the time-accurate resolution of vortex structures over many rotor revolutions PowerFLOW can provide.\u003C/p>\n\n\n\n\u003Ch3 class=\"wp-block-heading\" id=\"h-drones-and-rapid-multi-physics-concept-optimization\">\u003Cstrong>Drones and Rapid Multi-physics Concept Optimization\u003C/strong>\u003C/h3>\n\n\n\n\u003Cp>Small tactical drones — group 1 through group 3 unmanned systems operating at low altitudes and modest speeds — present a design challenge that is less about extreme aerodynamics and more about the speed and urgency of trade-off decisions that must be made early in the concept phase. These platforms are typically developed on compressed timescales with limited budgets, yet they must simultaneously satisfy tight requirements on aerodynamic endurance, acoustic signature (critical for covert operation), structural weight, thermal management of onboard electronics, and, increasingly, radar cross-section for survivability in contested airspace. Each of these disciplines interacts with the others: a body shape that minimizes radar cross-section may increase drag and reduce range; a lightweight composite structure may reflect radar energy in undesirable directions; a propulsion system optimized for efficiency may generate a thermal plume that is detectable by infrared sensors.\u003C/p>\n\n\n\n\u003Cp>Multi-physics simulations integrated within the \u003Ca href=\"https://www.3ds.com/3dexperience/\">\u003Cstrong>3D\u003C/strong>EXPERIENCE platform \u003C/a>are particularly well-suited to this compressed, multidisciplinary concept environment. With SIMULIA’s MODSIM solutions – offering automated processes that tightly integrate geometric modeling and simulation – a new drone body variant can be set up and running within hours rather than days — enabling genuine parametric sweeps across propeller diameter, body fineness ratio, inlet placement, and control surface geometry. CFD solutions, coupled to structural analysis for weight estimation and computational electromagnetics for RCS evaluation, enable a concept-phase tool chain in which dozens of design candidates can be scored against the full mission requirement set before a single physical prototype is committed to [4]. For a small tactical drone program operating under procurement pressure, that compression of the front-end design cycle — and the confidence it provides in the selected concept — can be decisive.\u003C/p>\n\n\n\n\u003Cp>To learn how these advances are being applied in practice, join Swen Noelting’s live webinar, \u003Cstrong>“Optimizing Performance, Stability & Robustness in Defense Aviation with Advanced CFD Simulation,”\u003C/strong> on \u003Cstrong>June 2, 2026\u003C/strong>. The session will explore how Lattice-Boltzmann-based CFD supports high-speed, unsteady flow and vibration analysis across defense aircraft, drones, missiles and launch vehicles. \u003Cstrong>Register here:\u003C/strong> \u003Ca href=\"https://events.3ds.com/advanced-cfd-defense-aviation-optimization\" target=\"_blank\" rel=\"noreferrer noopener\">https://events.3ds.com/advanced-cfd-defense-aviation-optimization\u003C/a>\u003C/p>\n\n\n\n\u003Chr class=\"wp-block-separator has-alpha-channel-opacity\" />\n\n\n\n\u003Cp>[1] Noelting, S., Fares, E. et al. Validation of PowerFLOW for transonic and supersonic flow regimes. \u003Cem>AIAA Paper\u003C/em> 2016-0585.\u003C/p>\n\n\n\n\u003Cp>[2] Duda, B., Fares, E. & Noelting, S. Application of a lattice-Boltzmann method to supersonic cavity flow. \u003Cem>AIAA Paper\u003C/em> 2016-0046.\u003C/p>\n\n\n\n\u003Cp>[3] Simpson, G. et al, Flight Test Reduction via Vibroacoustic Analysis, \u003Cem>Presented at AIAA SciTech, January 2026\u003C/em>.\u003C/p>\n\n\n\n\u003Cp>[4] Dassault Systèmes (2022). \u003Cem>SIMULIA for Defense: Multiphysics simulation across the platform lifecycle.\u003C/em> White paper. Vélizy-Villacoublay: Dassault Systèmes.\u003C/p>\n\n\n\n\u003Cfigure class=\"wp-block-image\">\u003Ca href=\"https://www.3ds.com/products-services/simulia/communities/simulia-community/?_gl=1*flg7k7*_ga*MTE2NzE3NTU0OS4xNzAxODA4NTI0*_ga_DYJDKXYEZ4*MTcwMzA5Mjk1NS4xMS4xLjE3MDMwOTQ5NTEuMTQuMC4w#_ga=2.128142988.12672350.1703092955-1167175549.1701808524\" target=\"_blank\" rel=\"noreferrer noopener\">\u003Cimg decoding=\"async\" src=\"https://blog-assets.3ds.com/uploads/2023/03/simulia-communities-email-signature.jpg\" alt=\"\" />\u003C/a>\u003C/figure>\n\n\n\n\u003Cp>\u003C/p>\n\n\n\n\u003Cp>\u003Cem>Interested in the latest in simulation? Looking for advice and best practices? Want to discuss simulation with fellow users and Dassault Systèmes experts?\u003C/em> \u003Cem>The \u003C/em>\u003Ca href=\"https://www.3ds.com/products-services/simulia/communities/learning-community/#_ga=2.186231657.1161542608.1587928634-d6a834f0-fe99-11e9-a0d7-7bef9ed67a15\" target=\"_blank\" rel=\"noreferrer noopener\">\u003Cem>SIMULIA Community\u003C/em>\u003C/a>\u003Cem> is the place to find the latest resources for SIMULIA software and to collaborate with other users. The key that unlocks the door of innovative thinking and knowledge building, the SIMULIA Community provides you with the tools you need to expand your knowledge, whenever and wherever\u003C/em>.\u003C/p>\n","2026-05-21T09:00:00",[],{"node":39,"__typename":50},{"nicename":40,"description":41,"slug":40,"name":42,"firstName":43,"lastName":44,"avatar":45,"__typename":49},"katherinecorey","Katie is the Editor of the SIMULIA blog, an expert in engineering and scientific communication, and a strategic digital marketer. Katie has a BA in English and Writing from the University of Rhode Island and a MS in Technical Communication from Northeastern University. She is also a proud SIMULIA advocate, passionate about democratizing simulation for all audiences. \r\n\r\nKatie is a native Rhode Islander who lives just outside of her favorite city, Providence. She is a true New Englander and loves sharing all the cool things NE has to offer.  She enjoys a variety of hobbies including history, astronomy, science/technology, science fiction, true crime, fashion and anything associated with nature and the outdoors. She is also mom to a 6-year old budding engineer and two crazy rescue pups.","Katie Corey","Katie","Corey",{"default":46,"url":47,"__typename":48},"mm","https://blog-assets.3ds.com/uploads/2024/11/cropped-katie-96x96.png","Avatar","User","NodeWithAuthorToUserConnectionEdge",{"edges":52,"nodes":60,"__typename":64},[53],{"isPrimary":54,"node":55,"__typename":59},true,{"slug":56,"name":57,"__typename":58},"design-simulation","Design & Simulation","Taxonomy_topic","PostToTaxonomy_topicConnectionEdge",[61],{"id":62,"name":57,"uri":63,"__typename":58},"dGVybTo4NTU5","/topics/design-simulation/","PostToTaxonomy_topicConnection",{"nodes":66,"__typename":72},[67],{"id":68,"name":69,"uri":70,"__typename":71},"dGVybTo4Nzcx","Fluids","/tags/fluids/","Taxonomy_tag","PostToTaxonomy_tagConnection",{"edges":74,"nodes":81,"__typename":83},[75],{"isPrimary":54,"node":76,"__typename":80},{"slug":77,"name":78,"__typename":79},"simulia","SIMULIA","Taxonomy_brand","PostToTaxonomy_brandConnectionEdge",[82],{"name":78,"slug":77,"__typename":79},"PostToTaxonomy_brandConnection",{"nodes":85,"__typename":89},[86],{"name":87,"__typename":88},"PowerFLOW","Taxonomy_keyword","PostToTaxonomy_keywordConnection",{"title":91,"metaDesc":92,"opengraphAuthor":93,"opengraphDescription":92,"opengraphTitle":20,"opengraphUrl":94,"opengraphSiteName":95,"opengraphPublishedTime":96,"opengraphModifiedTime":97,"twitterTitle":93,"twitterDescription":93,"readingTime":98,"metaRobotsNoindex":99,"__typename":100},"Beyond the Center of Flight: Fluid Simulations for Defense Industry","Learn how PowerFLOW addresses simulation challenges unique to military aircraft, including the defense industry's extreme requirements.","","https://blog-frontoffice-contrib-prd.itvpc.3ds.com/brands/simulia/beyond-center-flight-envelope-lbm-fluid-simulations-defense-industry/","Dassault Systèmes blog","2026-05-21T09:00:00+00:00","2026-05-21T14:55:56+00:00",6,"index","PostTypeSEO","Post","RootQueryToPostConnection",{},{},1779376201244]