{"id":557393,"date":"2024-11-05T18:17:53","date_gmt":"2024-11-05T18:17:53","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/esdu-070022011\/"},"modified":"2024-11-05T18:17:53","modified_gmt":"2024-11-05T18:17:53","slug":"esdu-070022011","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/esdu\/esdu-070022011\/","title":{"rendered":"ESDU 07002:2011"},"content":{"rendered":"<p>Viscous drag coefficient is defined in ESDU 07002 as the drag<br \/>\ncoefficient arising from all the effects of viscosity. Equations<br \/>\nand graphs are provided for predicting the viscous drag coefficient<br \/>\nof wings with sweep angles not exceeding 45\u00b0, aspect ratios not<br \/>\nexceeding 12, maximum section thickness to chord ratios within the<br \/>\nrange 0.1 to 0.2 and up to 10\u00b0 wash-in or wash-out.<\/p>\n<p>ESDU 07002 is applicable to values of lift coefficient at which<br \/>\nboth upper and lower surface boundary layers are fully attached, in<br \/>\nflow fields where shockwaves are not present. The method is<br \/>\napplicable to both straight-tapered and cranked wing planforms and<br \/>\nwhere the section geometry, including camber, either remains<br \/>\nunaltered or varies with spanwise location. Knowledge of a constant<br \/>\nchordwise location of boundary-layer transition across the span is<br \/>\nrequired. The method is based on a semi-empirical investigation<br \/>\nusing strip theory presented in ESDU 07003.<\/p>\n<p>As a means of testing the validity of the method, polars of<br \/>\npredicted and measured total drag coefficient for five wing<br \/>\ngeometries are compared. The predicted total drag coefficient was<br \/>\nobtained by adding values of inviscid trailing-vortex drag<br \/>\ncoefficient (predicted using ESDU 10022) to values of viscous drag<br \/>\ncoefficient obtained by the method of this Data Item. In most cases<br \/>\nthere is agreement to within about 10 drag counts<br \/>\n(<i>C<sub>D<\/sub><\/i> = 0.001) between the predicted data and the<br \/>\ntest data, over the ranges of lift coefficient where the boundary<br \/>\nlayers are indicated as being fully attached. The method is<br \/>\nappropriate for initial project calculations, where an agreement to<br \/>\nwithin 10 drag counts might be considered reasonable if the effects<br \/>\nof configuration changes rather than absolute values are of<br \/>\ninterest.<\/p>\n","protected":false},"excerpt":{"rendered":"<p><b>Wing viscous drag coefficient in shock-free attached flow<\/b><\/p>\n<table style=\"width: 100%\" border=\"0\" cellspacing=\"0\" cellpadding=\"0\">\n<tbody>\n<tr>\n<td>Published By<\/td>\n<td>Publication Date<\/td>\n<td>Number of Pages<\/td>\n<\/tr>\n<tr>\n<td><a href=\"https:\/\/pdfstandards.shop\/product-category\/publishers\/esdu\/\"><b>ESDU<\/b><\/a><\/td>\n<td>2011-12-01<\/td>\n<td>62<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":557402,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[2675],"product_tag":[],"class_list":{"0":"post-557393","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-esdu","8":"first","9":"instock","10":"sold-individually","11":"shipping-taxable","12":"purchasable","13":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/557393","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media\/557402"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=557393"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=557393"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=557393"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}