{"id":26884,"date":"2019-08-12T14:42:49","date_gmt":"2019-08-12T18:42:49","guid":{"rendered":"http:\/\/www.dodgegarage.com\/news-api\/?p=26884"},"modified":"2024-03-25T11:24:18","modified_gmt":"2024-03-25T15:24:18","slug":"out-of-thin-air","status":"publish","type":"post","link":"https:\/\/test.api.dodgegarage.com\/news\/showcase\/2019\/08\/out-of-thin-air.html","title":{"rendered":"Out of Thin Air"},"content":{"rendered":"\n

An inside look into FCA US LLC\u2019s\nAero-Acoustic Wind Tunnel<\/strong><\/p>\n\n\n\n

With only\nfour full-scale, dedicated, automotive wind tunnels in the United States (and\ntwo more under construction), the Aero-Acoustic Wind Tunnel at FCA US LLC\nHeadquarters in Auburn Hills, Michigan, and the scary smart aerodynamicists who\nuse it are the go-to resources for testing FCA US vehicles, including race\nvehicles.<\/p>\n\n\n\n

How It Began<\/strong><\/p>\n\n\n\n

Chrysler\nCorporation began talks on building the first reduced-scale wind tunnel in\n1927. Words tuned into action and a 1\/10 scale wind tunnel was built and\ntesting began. This would be one of the first dedicated automotive wind tunnels\nin the world.<\/p>\n\n\n\n

\"\"<\/figure><\/div>\n\n\n\n

By 1930, testing had led to the application, and the 1934 Chrysler and De Soto Air Flow vehicles were born. Coupe and Sedan models were available. These cars were among the first production vehicles to utilize wind tunnels and aerodynamics prior to entering the marketplace.<\/p>\n\n\n\n

\"dodge<\/figure>\n\n\n\n

Ebbs, Flows and the Aero-Evolution<\/strong><\/p>\n\n\n\n

The Great\nDepression took its toll on the \u201cAir Flow\u201d models, and Chrysler Corporation\nstopped production in 1937. The fascination with aerodynamics resurfaced in the\nmarketplace in the 1950s with styling effects like tail fins.<\/p>\n\n\n\n

In the\n1960s, when Chrysler Corp. was deep into stock car racing, the public really\ngot a taste of aerodynamics and its effects on speed and handling. Chrysler\nCorp. took 30+ years of learning to the track with the Dodge Charger Daytona\nand Plymouth Superbird. Both vehicles experienced extensive wind tunnel\ndevelopment and track testing. The combination proved to be the perfect recipe\nfor success with an 80% win rate in 1970.<\/p>\n\n\n\n

By 1973,\nconflict with the Middle East resulted in a U.S. oil embargo, which made\naerodynamics a key consideration for the FCA US vehicles. This time, they used\ntheir techniques to develop low-drag and fuel-efficient daily drivers.<\/p>\n\n\n\n

Now in the 21st<\/sup> century, FCA US continues to be among the leaders in the industry in aerodynamics with the development of racing, performance and production vehicles.<\/p>\n\n\n\n

\"dodge<\/figure>\n\n\n\n

Production Vehicle Testing<\/strong><\/p>\n\n\n\n

When it\ncomes to the wind tunnel testing of production vehicles, fuel efficiency is the\nprimary goal. FCA US aerodynamicists report aerodynamic drag in terms of the\ndrag area. This is the drag coefficient multiplied by the frontal area of the\nvehicle. The drag coefficient is the vehicle\u2019s non-dimensional shape\nefficiency. The scale factor is the frontal area. The drag area relates\ndirectly to the horsepower required to overcome aerodynamic drag and is the\nprimary consideration for improving highway fuel economy.<\/p>\n\n\n\n

\"overhead<\/figure>\n\n\n\n
\"model<\/figure><\/div>\n\n\n\n

Aerodynamics\ntesting and analysis begins several years before the start of production, \u201cWe\nwork concurrently with our Product Design Office to ensure FCA US products are\nbeautiful and efficient,\u201d said Greg Fadler, Manager of Aerodynamics Engineering\nand Wind Tunnel Operations.<\/p>\n\n\n\n

That begs\nthe question: If the model isn\u2019t in production, how can it be put into the\nwind tunnel for testing?<\/p>\n\n\n\n

\"model<\/figure><\/div>\n\n\n\n

There are\nactually two wind tunnels at the FCA US facility. One is full-scale, and one is\n3\/8 scale for early testing. 3\/8 scale clay models of all new vehicle designs\nare created and refined in the wind tunnel. These small clay models are\nextremely detailed \u2013 complete with 3D printed engines, transmissions, exhausts,\nbelly pans and suspensions. They are as close to their real vehicle counterparts\nas possible.<\/p>\n\n\n\n

\"dodge<\/figure><\/div>\n\n\n\n

\u201cWe test and\nrefine the small-scale model almost until we go to production,\u201d said Fadler,\n\u201cWe also build full-scale models and optimize them later in the process.\nFinally, we test the early production models to validate all of our previous\nwork. Two of our recent achievements are the 2019 Ram 1500 and the 2018 Jeep\u00ae<\/sub>\nWrangler. We improved the aerodynamic drag of both new models by 9% over the\nvehicles they replaced. That\u2019s huge in our world, considering that a typical\nprogram improvement of 3% to 5% is considered good.\u201d<\/p>\n\n\n\n

Performance Vehicle Testing<\/strong><\/p>\n\n\n\n

Optimization\nof aerodynamics is different for regular production, performance and racing\nvehicles.<\/p>\n\n\n\n

Regular\nproduction vehicles strive for maximum fuel efficiency and are speed limited so\nhigh-speed performance development is simplified.<\/p>\n\n\n\n

The main\ngoal for race vehicles is maximum speed. Therefore, the focus is the optimum\nbalance between downforce and drag to achieve the best possible elapsed times.\nOf course, predictable handling and high-speed stability are enablers to this\ngoal. While still important in most forms of racing, drag coefficient and fuel\neconomy are usually secondary considerations to maximum performance on a race\nvehicle. Aerodynamic efficiency is the lift-to-drag ratio (or downforce-to-drag\nratio). Optimization of this term is specific to each race track. The range of\nL\/D values are predetermined so the racecar can be set up for minimum lap times\nat each race track and the current weather conditions. In similar terms,\nincreasing downforce improves the speeds through corners, which is critical in\nmost forms of motorsports.<\/p>\n\n\n\n

SRT\u00ae<\/sup> models\nstrike a different balance between efficiency and performance than regular\nproduction and race vehicles. SRT products must still achieve the best possible\nfuel economy while delivering excellent handling and high-speed stability\nthroughout their operational envelope.<\/p>\n\n\n\n

For each\nvehicle type, regular production, SRT and race vehicles, wind tunnel testing allows\nthe FCA US Aero Team to measure drag, lift, side forces, rolling, pitching and\nyawing moments. Optimization of these six aero parameters is specific to each\nvehicle type and application.<\/p>\n\n\n\n

The FCA US\nfull-scale wind tunnel utilizes two boundary layer control systems, a suction\nslot and tangential blowing slot. These two features work in harmony to\nminimize the boundary layer thickness under the vehicle. The boundary layer is\nthe thin region between full-speed flow and non-moving flow at the floor. The thinner\nthe boundary layer, the better the wind tunnel simulates the real world. The\nfull-scale wind tunnel\u2019s nozzle size is a large 300 square-feet, which is large\nfor an open-jet, automotive wind tunnel. The tunnel can also test vehicles in\n+\/-180 degrees of yaw, allowing it to produce winds on the vehicle from every\npossible angle, including backwards! The wind tunnel\u2019s weigh-beam balance\nsystem is accurate to within +\/-0.01%.<\/p>\n\n\n\n

Ultimately, the goals of the FCA US Aero engineers, facilities and testing are obvious. They are all focused to deliver excellent results for production, performance and racing vehicles.<\/p>\n\n\n\n

\"funny<\/figure>\n","protected":false},"excerpt":{"rendered":"

An inside look into FCA US LLC\u2019s Aero-Acoustic Wind Tunnel With only four full-scale, dedicated, automotive wind tunnels in the United States (and two more under construction), the Aero-Acoustic Wind Tunnel at FCA US LLC Headquarters in Auburn Hills, Michigan, and the scary smart aerodynamicists who use it are the go-to resources for testing FCA US vehicles, including race vehicles. How It Began Chrysler Corporation began talks on building the first reduced-scale wind tunnel in 1927. Words tuned into action and a 1\/10 scale wind tunnel was built and testing […]<\/p>\n","protected":false},"author":27,"featured_media":27133,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[638],"tags":[],"class_list":["post-26884","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-showcase"],"acf":[],"custom_fields":{"post_thumbnail_image":"https:\/\/test.api.dodgegarage.com\/news\/wp-content\/uploads\/2019\/08\/feature-9.jpg","icon_selection":"article","external_link":"","featured_article":[],"upload_background_image":""},"_links":{"self":[{"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/posts\/26884"}],"collection":[{"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/users\/27"}],"replies":[{"embeddable":true,"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/comments?post=26884"}],"version-history":[{"count":7,"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/posts\/26884\/revisions"}],"predecessor-version":[{"id":27146,"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/posts\/26884\/revisions\/27146"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/media\/27133"}],"wp:attachment":[{"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/media?parent=26884"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/categories?post=26884"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/test.api.dodgegarage.com\/news\/wp-json\/wp\/v2\/tags?post=26884"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}