{"id":5883,"date":"2020-03-10T09:00:14","date_gmt":"2020-03-10T08:00:14","guid":{"rendered":"https:\/\/www.presticebdt.com\/?p=5883"},"modified":"2023-09-24T13:21:00","modified_gmt":"2023-09-24T11:21:00","slug":"3-must-component-for-wind-tunnel-design","status":"publish","type":"post","link":"https:\/\/www.presticebdt.com\/el\/3-must-component-for-wind-tunnel-design\/","title":{"rendered":"\u039a\u03b1\u03c4\u03b1\u03bd\u03cc\u03b7\u03c3\u03b7 \u03c4\u03bf\u03c5 \u03c3\u03c7\u03b5\u03b4\u03b9\u03b1\u03c3\u03bc\u03bf\u03cd \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2 | 3 \u03b1\u03c0\u03b1\u03c1\u03b1\u03af\u03c4\u03b7\u03c4\u03b1 \u03c3\u03c5\u03c3\u03c4\u03b1\u03c4\u03b9\u03ba\u03ac"},"content":{"rendered":"<section  class='av_textblock_section av-k4odsn2t-022461ea4f00186a837ce1192d07fe83'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><h1 style=\"text-align: center;\">\u039a\u03b1\u03c4\u03b1\u03bd\u03cc\u03b7\u03c3\u03b7 \u03c4\u03bf\u03c5 \u03c3\u03c7\u03b5\u03b4\u03b9\u03b1\u03c3\u03bc\u03bf\u03cd \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2<strong><br \/>\n<\/strong><\/h1>\n<h2 style=\"text-align: center;\">\u0391\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1 \u03ba\u03bb\u03b5\u03b9\u03c3\u03c4\u03bf\u03cd \u03ba\u03c5\u03ba\u03bb\u03ce\u03bc\u03b1\u03c4\u03bf\u03c2: \u03b8\u03ac\u03bb\u03b1\u03bc\u03bf\u03c2 \u03ba\u03b1\u03b8\u03af\u03b6\u03b7\u03c3\u03b7\u03c2, \u03c3\u03c5\u03b3\u03ba\u03bb\u03af\u03bd\u03bf\u03c5\u03c3\u03b1 \u03ba\u03b1\u03b9 \u03ad\u03bb\u03b9\u03ba\u03b1<\/h2>\n<h3><\/h3>\n<div id=\"attachment_5892\" style=\"width: 480px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.presticebdt.com\/wp-content\/uploads\/2020\/03\/7.jpg\"><img decoding=\"async\" aria-describedby=\"caption-attachment-5892\" class=\"wp-image-5892 size-full\" src=\"https:\/\/www.presticebdt.com\/wp-content\/uploads\/2020\/03\/7.jpg\" alt=\"\u03a3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1 \u03b1\u03bd\u03ad\u03bc\u03bf\u03c5 \u03ba\u03bb\u03b5\u03b9\u03c3\u03c4\u03bf\u03cd \u03ba\u03c5\u03ba\u03bb\u03ce\u03bc\u03b1\u03c4\u03bf\u03c2 \" width=\"470\" height=\"250\" title=\"\" srcset=\"https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/7-300x160.jpg?lossy=2&amp;strip=1&amp;webp=1 300w, https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/7.jpg?lossy=2&amp;strip=1&amp;webp=1 470w\" sizes=\"(max-width: 470px) 100vw, 470px\" \/><\/a><p id=\"caption-attachment-5892\" class=\"wp-caption-text\">Closed circuit wind tunnel of Ferrari<\/p><\/div>\n<p>\u0391\u03c5\u03c4\u03cc \u03b5\u03af\u03bd\u03b1\u03b9 \u03c4\u03bf \u03b4\u03b5\u03cd\u03c4\u03b5\u03c1\u03bf \u03bc\u03ac\u03b8\u03b7\u03bc\u03ac \u03bc\u03b1\u03c2 \u03c3\u03c7\u03b5\u03c4\u03b9\u03ba\u03ac \u03bc\u03b5 \u03c4\u03bf \u03c3\u03c7\u03b5\u03b4\u03b9\u03b1\u03c3\u03bc\u03cc \u03ba\u03b1\u03b9 \u03c4\u03b7 \u03b4\u03b9\u03b1\u03c3\u03c4\u03b1\u03c3\u03b9\u03bf\u03bb\u03cc\u03b3\u03b7\u03c3\u03b7 \u03c4\u03b7\u03c2 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2. \u0391\u03bd \u03c7\u03ac\u03c3\u03b1\u03c4\u03b5 \u03c4\u03bf \u03c0\u03c1\u03ce\u03c4\u03bf \u03bc\u03ad\u03c1\u03bf\u03c2, \u03bc\u03c0\u03bf\u03c1\u03b5\u03af\u03c4\u03b5 \u03bd\u03b1 \u03c4\u03bf \u03c0\u03ac\u03c1\u03b5\u03c4\u03b5 <a href=\"https:\/\/www.presticebdt.com\/el\/the-design-of-a-closed-circuit-wind-tunnel\/\">\u03b5\u03b4\u03ce<\/a>.<\/p>\n<h3>\u03a3\u03c7\u03b5\u03b4\u03b9\u03b1\u03c3\u03bc\u03cc\u03c2 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2 \u03ba\u03bb\u03b5\u03b9\u03c3\u03c4\u03bf\u03cd \u03ba\u03c5\u03ba\u03bb\u03ce\u03bc\u03b1\u03c4\u03bf\u03c2: \u03bf \u03b8\u03ac\u03bb\u03b1\u03bc\u03bf\u03c2 \u03ba\u03b1\u03b8\u03af\u03b6\u03b7\u03c3\u03b7\u03c2.<\/h3>\n<p>\u03a3\u03b5 \u03b1\u03c5\u03c4\u03cc \u03c4\u03bf \u03c4\u03bc\u03ae\u03bc\u03b1 \u03bf \u03b1\u03ad\u03c1\u03b1\u03c2 \u03c7\u03b5\u03b9\u03c1\u03b1\u03b3\u03c9\u03b3\u03b5\u03af\u03c4\u03b1\u03b9 \u03b5\u03c0\u03b5\u03b9\u03b4\u03ae \u03c0\u03c1\u03ad\u03c0\u03b5\u03b9 \u03bd\u03b1 \u03b4\u03b9\u03b1\u03c3\u03c0\u03ac\u03c3\u03c9 \u03c4\u03b7\u03bd \u03c4\u03cd\u03c1\u03b2\u03b7, <strong>\u03b9\u03c3\u03b9\u03ce\u03c3\u03c4\u03b5 \u03c4\u03b7 \u03c1\u03bf\u03ae<\/strong> (\u03b5\u03c5\u03b8\u03c5\u03b3\u03c1\u03b1\u03bc\u03bc\u03af\u03c3\u03c4\u03b5 \u03c4\u03bf \u03bc\u03b5 \u03c4\u03bf\u03bd \u03ac\u03be\u03bf\u03bd\u03b1 \u03c4\u03b7\u03c2 \u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2), \u03ce\u03c3\u03c4\u03b5 \u03bd\u03b1 \u03c0\u03b1\u03c1\u03bf\u03c5\u03c3\u03b9\u03ac\u03b6\u03b5\u03c4\u03b1\u03b9 \u03bf\u03bc\u03bf\u03b9\u03bf\u03b3\u03b5\u03bd\u03ae\u03c2 \u03ba\u03b1\u03b9 \u03bf\u03bc\u03bf\u03b9\u03cc\u03bc\u03bf\u03c1\u03c6\u03b7 \u03c1\u03bf\u03ae \u03c3\u03c4\u03bf \u03b8\u03ac\u03bb\u03b1\u03bc\u03bf \u03b4\u03bf\u03ba\u03b9\u03bc\u03ae\u03c2.<\/p>\n<div id=\"attachment_5896\" style=\"width: 336px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.presticebdt.com\/wp-content\/uploads\/2020\/03\/18.jpg\"><img decoding=\"async\" aria-describedby=\"caption-attachment-5896\" class=\"wp-image-5896\" src=\"https:\/\/www.presticebdt.com\/wp-content\/uploads\/2020\/03\/18.jpg\" alt=\"\u039a\u03ad\u03bb\u03c5\u03c6\u03bf\u03c2 \u03bc\u03b5\u03bb\u03b9\u03bf\u03cd \u03c3\u03b5 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ad\u03c2 \u03c3\u03b5 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\" width=\"326\" height=\"247\" title=\"\" srcset=\"https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/18-300x227.jpg?lossy=2&amp;strip=1&amp;webp=1 300w, https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/18.jpg?lossy=2&amp;strip=1&amp;webp=1 508w\" sizes=\"(max-width: 326px) 100vw, 326px\" \/><\/a><p id=\"caption-attachment-5896\" class=\"wp-caption-text\">\u03a0\u03b1\u03c1\u03ac\u03b4\u03b5\u03b9\u03b3\u03bc\u03b1 \u03ba\u03b7\u03c1\u03ae\u03b8\u03c1\u03b1\u03c2 \u03c3\u03b5 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ae \u03c3\u03b5 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1.<\/p><\/div>\n<p>\u03a4\u03bf <strong>\u03bf \u03b8\u03ac\u03bb\u03b1\u03bc\u03bf\u03c2 \u03ba\u03b1\u03b8\u03af\u03b6\u03b7\u03c3\u03b7\u03c2 \u03b1\u03c0\u03bf\u03c4\u03b5\u03bb\u03b5\u03af\u03c4\u03b1\u03b9 \u03b1\u03c0\u03cc \u03bc\u03b9\u03b1 \u03ba\u03b7\u03c1\u03ae\u03b8\u03c1\u03b1<\/strong> (\u03ba\u03c5\u03ba\u03bb\u03b9\u03ba\u03ae\u03c2 \u03ae \u03b5\u03be\u03b1\u03b3\u03c9\u03bd\u03b9\u03ba\u03ae\u03c2 \u03b4\u03b9\u03b1\u03c4\u03bf\u03bc\u03ae\u03c2) \u03c0\u03bf\u03c5 \u03c3\u03b1\u03c2 \u03b5\u03c0\u03b9\u03c4\u03c1\u03ad\u03c0\u03bf\u03c5\u03bd \u03bd\u03b1 \u03b9\u03c3\u03b9\u03ce\u03c3\u03b5\u03c4\u03b5 \u03c4\u03bf \u03c1\u03b5\u03cd\u03bc\u03b1 \u03c4\u03cc\u03c3\u03bf \u03c3\u03c4\u03bf \u03bf\u03c1\u03b9\u03b6\u03cc\u03bd\u03c4\u03b9\u03bf \u03cc\u03c3\u03bf \u03ba\u03b1\u03b9 \u03c3\u03c4\u03bf \u03ba\u03b1\u03c4\u03b1\u03ba\u03cc\u03c1\u03c5\u03c6\u03bf \u03b5\u03c0\u03af\u03c0\u03b5\u03b4\u03bf.<\/p>\n<p>\u0388\u03bd\u03b1 \u03ac\u03bb\u03bb\u03bf \u03b1\u03c0\u03bf\u03c4\u03ad\u03bb\u03b5\u03c3\u03bc\u03b1 \u03c4\u03b7\u03c2 \u03ba\u03b7\u03c1\u03ae\u03b8\u03c1\u03b1\u03c2 \u03b5\u03af\u03bd\u03b1\u03b9 \u03b1\u03c5\u03c4\u03cc \u03c4\u03b7\u03c2 <strong>\u03bc\u03b5\u03c1\u03b9\u03ba\u03cc \u03c3\u03c0\u03ac\u03c3\u03b9\u03bc\u03bf \u03c4\u03b7\u03c2 \u03c4\u03cd\u03c1\u03b2\u03b7\u03c2<\/strong> \u03c4\u03b7\u03c2 \u03c1\u03bf\u03ae\u03c2 \u03b1\u03bd\u03ac\u03bb\u03bf\u03b3\u03b1 \u03bc\u03b5 \u03c4\u03b7 \u03c4\u03ac\u03be\u03b7 \u03bc\u03b5\u03b3\u03ad\u03b8\u03bf\u03c5\u03c2 \u03c4\u03b7\u03c2 \u03b4\u03b9\u03b1\u03bc\u03ad\u03c4\u03c1\u03bf\u03c5 \u03c4\u03c9\u03bd \u03c4\u03bc\u03b7\u03bc\u03ac\u03c4\u03c9\u03bd.<\/p>\n<h3>\u0393\u03b9\u03b1\u03c4\u03af \u03bf\u03b9 \u03ba\u03b7\u03c1\u03ae\u03b8\u03c1\u03b5\u03c2 \u03b5\u03af\u03bd\u03b1\u03b9 \u03c3\u03b7\u03bc\u03b1\u03bd\u03c4\u03b9\u03ba\u03ad\u03c2 \u03c3\u03c4\u03b7\u03bd \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1;<\/h3>\n<p>\u039f \u03b9\u03c3\u03b9\u03c9\u03c4\u03ae\u03c2 \u03c1\u03bf\u03ae\u03c2 \u03c4\u03cd\u03c0\u03bf\u03c5 \u03ba\u03c5\u03c8\u03ad\u03bb\u03b7\u03c2 \u03b1\u03c0\u03bf\u03c4\u03b5\u03bb\u03b5\u03af\u03c4\u03b1\u03b9 \u03b1\u03c0\u03cc <strong>\u03bc\u03b9\u03b1 \u03c3\u03b5\u03b9\u03c1\u03ac \u03c3\u03c9\u03bb\u03ae\u03bd\u03c9\u03bd \u03bc\u03b9\u03ba\u03c1\u03ae\u03c2 \u03b4\u03b9\u03b1\u03bc\u03ad\u03c4\u03c1\u03bf\u03c5<\/strong> (generally between 5 and 7 mm) and about fifteen centimeters long. These tubes are arranged coaxially to the duct in which they are located (generally in the area of \u200b\u200bthe tunnel where the speeds are as low as possible to minimize pressure drops) and are glued to each other to form structures, generally hexagonal (similar to honeycombs, hence the name), which cover the entire area of \u200b\u200bthe section where they are placed.<\/p>\n<h4>\u0391\u03c2 \u03c3\u03c7\u03b5\u03b4\u03b9\u03ac\u03c3\u03bf\u03c5\u03bc\u03b5 \u03ba\u03b7\u03c1\u03ae\u03b8\u03c1\u03b1 \u03b3\u03b9\u03b1 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ad\u03c2 \u03c3\u03b5 \u03b1\u03b5\u03c1\u03bf\u03b4\u03c5\u03bd\u03b1\u03bc\u03b9\u03ba\u03ae \u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1.<\/h4>\n<p>\u0395\u03bd\u03b4\u03b5\u03b9\u03ba\u03c4\u03b9\u03ba\u03ac \u03b1\u03bd\u03b1\u03c6\u03ad\u03c1\u03b5\u03c4\u03b1\u03b9 \u03cc\u03c4\u03b9, \u03c3\u03b5 \u03ad\u03bd\u03b1<strong> \u03b3\u03ba\u03b1\u03bb\u03b5\u03c1\u03af \u03bc\u03b5 \u03c4\u03bc\u03ae\u03bc\u03b1 \u03cc\u03c0\u03bf\u03c5 \u03c4\u03bf 3,6 x 0,9<\/strong> \u03bc\u03b5\u03c4\u03c1\u03b7\u03c4\u03ae \u03ba\u03b7\u03c1\u03ae\u03b8\u03c1\u03b1 \u03b5\u03af\u03bd\u03b1\u03b9 \u03c0\u03b1\u03c1\u03bf\u03cd\u03c3\u03b1, \u03ba\u03ac\u03c4\u03b9 \u03c3\u03b1\u03bd <strong>78.000 \u03c3\u03c9\u03bb\u03ae\u03bd\u03b5\u03c2 \u03b4\u03b9\u03b1\u03bc\u03ad\u03c4\u03c1\u03bf\u03c5 7 mm<\/strong> \u03c4\u03b1\u03ba\u03c4\u03bf\u03c0\u03bf\u03b9\u03bf\u03cd\u03bd\u03c4\u03b1\u03b9. \u0397 \u03b4\u03bf\u03c5\u03bb\u03b5\u03b9\u03ac \u03c4\u03c9\u03bd \u03ba\u03c5\u03c8\u03b5\u03bb\u03ce\u03bd \u03b5\u03af\u03bd\u03b1\u03b9 \u03bd\u03b1 \u03b5\u03be\u03b1\u03bb\u03b5\u03af\u03c8\u03bf\u03c5\u03bd \u03c4\u03b9\u03c2 \u03c3\u03c5\u03bd\u03b9\u03c3\u03c4\u03ce\u03c3\u03b5\u03c2 \u03c4\u03b7\u03c2 \u03c4\u03b1\u03c7\u03cd\u03c4\u03b7\u03c4\u03b1\u03c2 \u03c4\u03b7\u03c2 \u03c1\u03bf\u03ae\u03c2 \u03ba\u03ac\u03b8\u03b5\u03c4\u03b1 \u03c3\u03c4\u03b1 \u03c4\u03bf\u03b9\u03c7\u03ce\u03bc\u03b1\u03c4\u03b1 \u03ba\u03b1\u03b9 \u03bd\u03b1 \u03ba\u03b1\u03c4\u03b5\u03c5\u03b8\u03cd\u03bd\u03bf\u03c5\u03bd \u03c4\u03b7 \u03c1\u03bf\u03ae \u03bc\u03cc\u03bd\u03bf \u03ba\u03b1\u03b9 \u03cc\u03c3\u03bf \u03c4\u03bf \u03b4\u03c5\u03bd\u03b1\u03c4\u03cc\u03bd \u03c0\u03b5\u03c1\u03b9\u03c3\u03c3\u03cc\u03c4\u03b5\u03c1\u03bf \u03c0\u03c1\u03bf\u03c2 \u03c4\u03b7\u03bd \u03ba\u03b1\u03c4\u03b5\u03cd\u03b8\u03c5\u03bd\u03c3\u03b7 \u03c4\u03bf\u03c5 \u03ac\u03be\u03bf\u03bd\u03b1 \u03c4\u03bf\u03c5 \u03b1\u03b3\u03c9\u03b3\u03bf\u03cd. \u0393\u03b5\u03bd\u03b9\u03ba\u03ac, \u03bf\u03b9 \u03ba\u03c5\u03c8\u03ad\u03bb\u03b5\u03c2 \u03ae \u03bf\u03b9 \u03ba\u03b7\u03c1\u03ae\u03b8\u03c1\u03b5\u03c2 \u03c4\u03bf\u03c0\u03bf\u03b8\u03b5\u03c4\u03bf\u03cd\u03bd\u03c4\u03b1\u03b9<strong> \u03bb\u03af\u03b3\u03bf \u03c0\u03c1\u03b9\u03bd \u03b1\u03c0\u03cc \u03c4\u03b7\u03bd \u03ad\u03bd\u03b1\u03c1\u03be\u03b7 \u03c4\u03b7\u03c2 \u03c3\u03cd\u03b3\u03ba\u03bb\u03b9\u03c3\u03b7\u03c2 \u03ba\u03b1\u03b9 \u03b5\u03c0\u03bf\u03bc\u03ad\u03bd\u03c9\u03c2 \u03bb\u03af\u03b3\u03bf \u03c0\u03c1\u03b9\u03bd \u03b1\u03c0\u03cc \u03c4\u03bf \u03b8\u03ac\u03bb\u03b1\u03bc\u03bf \u03b4\u03bf\u03ba\u03b9\u03bc\u03ce\u03bd<\/strong>.<\/p>\n<p style=\"text-align: center;\">\\(\\begin{align} \\frac{u_{ex}\u2019}{u_{en}\u2019}=\\frac{1}{1+k}^{\\frac{n}{2}} \\end{align}\\)<\/p>\n<p>\u0394\u03b5\u03b4\u03bf\u03bc\u03ad\u03bd\u03bf\u03c5 \u03cc\u03c4\u03b9 \u03c4\u03bf \u03bc\u03ad\u03b3\u03b5\u03b8\u03bf\u03c2 \u03c4\u03c9\u03bd \u03c3\u03c4\u03c1\u03bf\u03b2\u03af\u03bb\u03c9\u03bd \u03b5\u03be\u03b1\u03ba\u03bf\u03bb\u03bf\u03c5\u03b8\u03b5\u03af \u03bd\u03b1 \u03c0\u03b1\u03c1\u03b1\u03bc\u03ad\u03bd\u03b5\u03b9 \u03c3\u03b7\u03bc\u03b1\u03bd\u03c4\u03b9\u03ba\u03cc, \u03c0\u03c1\u03ad\u03c0\u03b5\u03b9 \u03bd\u03b1 \u03c4\u03bf\u03c5\u03c2 \u03c7\u03c4\u03c5\u03c0\u03ae\u03c3\u03c9 \u03bf\u03c1\u03b9\u03c3\u03c4\u03b9\u03ba\u03ac \u03bc\u03b5 \u03c4\u03b7 \u03c7\u03c1\u03ae\u03c3\u03b7 \u03b5\u03bd\u03cc\u03c2 \u03ae \u03c0\u03b5\u03c1\u03b9\u03c3\u03c3\u03cc\u03c4\u03b5\u03c1\u03c9\u03bd \u03b4\u03b9\u03ba\u03c4\u03cd\u03c9\u03bd \u03c3\u03c4\u03b1 \u03bf\u03c0\u03bf\u03af\u03b1 \u03b7 \u03c1\u03bf\u03ae \u03c5\u03c6\u03af\u03c3\u03c4\u03b1\u03c4\u03b1\u03b9 \u03bc\u03b9\u03b1 <strong>\u03b4\u03c1\u03b1\u03c3\u03c4\u03b9\u03ba\u03ae \u03c3\u03cd\u03bd\u03b8\u03bb\u03b9\u03c8\u03b7 \u03ba\u03b1\u03b9 \u03b7 \u03ba\u03bb\u03af\u03bc\u03b1\u03ba\u03b1 \u03c4\u03cd\u03c1\u03b2\u03b7\u03c2 \u03c0\u03c1\u03bf\u03c6\u03b1\u03bd\u03ce\u03c2 \u03bc\u03b5\u03b9\u03ce\u03bd\u03b5\u03c4\u03b1\u03b9<\/strong>.<\/p>\n<p>Considering the Dryden &amp; Schubauer relationship:<\/p>\n<p>\u03a0\u03bf\u03cd:<\/p>\n<p>\\( u_{ex}&#8217;\u00a0 \\):<strong> \u03b4\u03b9\u03b1\u03ba\u03c5\u03bc\u03ac\u03bd\u03c3\u03b5\u03b9\u03c2 \u03ba\u03b1\u03c4\u03ac \u03c4\u03b7\u03bd \u03ad\u03be\u03bf\u03b4\u03bf \u03b1\u03c0\u03cc \u03c4\u03bf \u03b4\u03af\u03ba\u03c4\u03c5\u03bf<br \/>\n<\/strong><\/p>\n<p>\\( u_{en}' \\): \u03c0\u03bb\u03ad\u03b3\u03bc\u03b1<strong> \u03b4\u03b9\u03b1\u03ba\u03c5\u03bc\u03ac\u03bd\u03c3\u03b5\u03b9\u03c2 \u03b5\u03b9\u03c3\u03c1\u03bf\u03ce\u03bd<\/strong><\/p>\n<p>\\( k \\): \u03c0\u03bb\u03ad\u03b3\u03bc\u03b1 <strong>\u03b1\u03c0\u03cc\u03b4\u03bf\u03c3\u03b7 \u03c0\u03bf\u03c5 \u03ba\u03b1\u03b8\u03bf\u03c1\u03af\u03b6\u03b5\u03c4\u03b1\u03b9 \u03b1\u03c0\u03cc \u03c4\u03bf\u03bd \u03ba\u03b1\u03c4\u03b1\u03c3\u03ba\u03b5\u03c5\u03b1\u03c3\u03c4\u03ae<\/strong>r<\/p>\n<p>\\( n \\): <strong>\u03b1\u03c1\u03b9\u03b8\u03bc\u03cc\u03c2 \u03c0\u03bb\u03b5\u03b3\u03bc\u03ac\u03c4\u03c9\u03bd<br \/>\n<\/strong><\/p>\n<h5><a href=\"https:\/\/www.presticebdt.com\/wp-content\/uploads\/2020\/03\/4.jpg\"><img decoding=\"async\" class=\"aligncenter wp-image-5890\" src=\"https:\/\/www.presticebdt.com\/wp-content\/uploads\/2020\/03\/4.jpg\" alt=\"\u03a3\u03c7\u03b5\u03b4\u03b9\u03b1\u03c3\u03bc\u03cc\u03c2 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2 \u03c4\u03bc\u03ae\u03bc\u03b1\u03c4\u03bf\u03c2 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ae\u03c2\" width=\"590\" height=\"332\" title=\"\" srcset=\"https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/4.jpg?size=118x66&amp;lossy=2&amp;strip=1&amp;webp=1 118w, https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/4.jpg?size=236x133&amp;lossy=2&amp;strip=1&amp;webp=1 236w, https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/4-300x169.jpg?lossy=2&amp;strip=1&amp;webp=1 300w, https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/4.jpg?size=354x199&amp;lossy=2&amp;strip=1&amp;webp=1 354w, https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/4.jpg?lossy=2&amp;strip=1&amp;webp=1 480w\" sizes=\"(max-width: 590px) 100vw, 590px\" \/><\/a><\/h5>\n<h5>\u039a\u03c5\u03c8\u03ad\u03bb\u03b5\u03c2 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2: \u03b9\u03c3\u03b9\u03c9\u03c4\u03ae\u03c2 \u03c1\u03bf\u03ae\u03c2.<\/h5>\n<p>\u03a4\u03b1 \u03b4\u03af\u03c7\u03c4\u03c5\u03b1 \u03ad\u03c7\u03bf\u03c5\u03bd \u03c9\u03c2 \u03b1\u03c0\u03bf\u03c3\u03c4\u03bf\u03bb\u03ae<strong> \u03c3\u03c0\u03ac\u03c3\u03b9\u03bc\u03bf \u03b4\u03bf\u03bc\u03ce\u03bd \u03c3\u03c4\u03c1\u03bf\u03b2\u03b9\u03bb\u03b9\u03c3\u03bc\u03bf\u03cd \u03bc\u03b5\u03b3\u03ac\u03bb\u03b7\u03c2 \u03ba\u03bb\u03af\u03bc\u03b1\u03ba\u03b1\u03c2<\/strong> \u03ba\u03b1\u03b9 \u03c4\u03b7 \u03bc\u03b5\u03c4\u03b1\u03c4\u03c1\u03bf\u03c0\u03ae \u03c4\u03bf\u03c5\u03c2 \u03c3\u03b5 \u03bc\u03b9\u03ba\u03c1\u03cc\u03c4\u03b5\u03c1\u03b5\u03c2 \u03ba\u03b1\u03b9 \u03c0\u03b9\u03bf \u03bf\u03bc\u03bf\u03b9\u03cc\u03bc\u03bf\u03c1\u03c6\u03b5\u03c2 \u03c3\u03c4\u03c1\u03bf\u03b2\u03b9\u03bb\u03b9\u03b6\u03cc\u03bc\u03b5\u03bd\u03b5\u03c2 \u03b4\u03bf\u03bc\u03ad\u03c2, \u03ba\u03b1\u03b8\u03b9\u03c3\u03c4\u03ce\u03bd\u03c4\u03b1\u03c2 \u03ad\u03c4\u03c3\u03b9 \u03c4\u03bf <strong>\u03c0\u03b9\u03bf \u03bf\u03bc\u03bf\u03b9\u03cc\u03bc\u03bf\u03c1\u03c6\u03bf \u03c0\u03c1\u03bf\u03c6\u03af\u03bb \u03c4\u03b1\u03c7\u03cd\u03c4\u03b7\u03c4\u03b1\u03c2<\/strong>. \u03a4\u03b1 \u03b4\u03af\u03ba\u03c4\u03c5\u03b1, \u03c9\u03c3\u03c4\u03cc\u03c3\u03bf, \u03ad\u03c7\u03bf\u03c5\u03bd, \u03cc\u03c0\u03c9\u03c2 \u03ad\u03c7\u03b5\u03b9 \u03ae\u03b4\u03b7 \u03b1\u03bd\u03b1\u03c6\u03b5\u03c1\u03b8\u03b5\u03af, \u03c4\u03bf \u03b5\u03bb\u03ac\u03c4\u03c4\u03c9\u03bc\u03b1 \u03c4\u03b7\u03c2 \u03b5\u03ba\u03c4\u03c1\u03bf\u03c0\u03ae\u03c2 \u03c4\u03b7\u03c2 \u03ba\u03cd\u03c1\u03b9\u03b1\u03c2 \u03ba\u03b1\u03c4\u03b5\u03cd\u03b8\u03c5\u03bd\u03c3\u03b7\u03c2 \u03c4\u03b7\u03c2 \u03c1\u03bf\u03ae\u03c2, \u03b5\u03af\u03bd\u03b1\u03b9 \u03b5\u03c0\u03bf\u03bc\u03ad\u03bd\u03c9\u03c2 \u03b1\u03c0\u03b1\u03c1\u03b1\u03af\u03c4\u03b7\u03c4\u03bf \u03bd\u03b1 \u03c4\u03bf\u03c0\u03bf\u03b8\u03b5\u03c4\u03b7\u03b8\u03bf\u03cd\u03bd \u03b3\u03cd\u03c1\u03c9 \u03b1\u03c0\u03cc \u03c3\u03c4\u03bf\u03b9\u03c7\u03b5\u03af\u03b1 (\u03c4\u03b9\u03c2 \u03ba\u03b7\u03c1\u03ae\u03b8\u03c1\u03b5\u03c2) \u03b9\u03ba\u03b1\u03bd\u03ac \u03bd\u03b1 \"<strong>\u03af\u03c3\u03b9\u03c9\u03bc\u03b1<\/strong>\" \u03b7 \u03c1\u03bf\u03ae. \u03a0\u03c1\u03cc\u03ba\u03b5\u03b9\u03c4\u03b1\u03b9 \u03b3\u03b9\u03b1 \u03b5\u03be\u03b1\u03c1\u03c4\u03ae\u03bc\u03b1\u03c4\u03b1 \u03c0\u03bf\u03c5 \u03c4\u03b5\u03af\u03bd\u03bf\u03c5\u03bd \u03bd\u03b1 \u03bb\u03b5\u03c1\u03ce\u03bd\u03bf\u03bd\u03c4\u03b1\u03b9 \u03ba\u03b1\u03b9 \u03b5\u03c0\u03bf\u03bc\u03ad\u03bd\u03c9\u03c2, \u03cc\u03c0\u03c9\u03c2 \u03ba\u03b1\u03b9 \u03bf\u03b9 \u03ba\u03b7\u03c1\u03ae\u03b8\u03c1\u03b5\u03c2, \u03c7\u03c1\u03b5\u03b9\u03ac\u03b6\u03bf\u03bd\u03c4\u03b1\u03b9 \u03c3\u03c5\u03c7\u03bd\u03ae \u03c3\u03c5\u03bd\u03c4\u03ae\u03c1\u03b7\u03c3\u03b7. \u039c\u03c0\u03bf\u03c1\u03b5\u03af\u03c4\u03b5 \u03bd\u03b1 \u03b2\u03c1\u03b5\u03af\u03c4\u03b5 \u03c0\u03b5\u03c1\u03b9\u03c3\u03c3\u03cc\u03c4\u03b5\u03c1\u03b5\u03c2 \u03c0\u03bb\u03b7\u03c1\u03bf\u03c6\u03bf\u03c1\u03af\u03b5\u03c2 \u03c3\u03c7\u03b5\u03c4\u03b9\u03ba\u03ac \u03bc\u03b5 \u03c4\u03b9\u03c2 \u03ba\u03c5\u03c8\u03ad\u03bb\u03b5\u03c2 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2 \u03c3\u03c4\u03bf <a href=\"https:\/\/en.wikipedia.org\/wiki\/Flow_straightener\" rel=\"nofollow noopener\" target=\"_blank\">Wiki<\/a>.<\/p>\n<h4>\u0397 \u03c1\u03bf\u03ae \u03c0\u03c1\u03ad\u03c0\u03b5\u03b9 \u03bd\u03b1 \u03b5\u03c0\u03b9\u03c4\u03b1\u03c7\u03c5\u03bd\u03b8\u03b5\u03af: \u03c4\u03bf \u03c3\u03c5\u03b3\u03ba\u03bb\u03af\u03bd\u03bf\u03bd \u03c4\u03bc\u03ae\u03bc\u03b1 \u03c3\u03b5 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ad\u03c2 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2.<\/h4>\n<p>\u03a4\u03bf \u03c4\u03b5\u03bb\u03b5\u03c5\u03c4\u03b1\u03af\u03bf \u03c4\u03bc\u03ae\u03bc\u03b1 \u03c0\u03c1\u03b9\u03bd \u03b1\u03c0\u03cc \u03c4\u03bf \u03b8\u03ac\u03bb\u03b1\u03bc\u03bf \u03b4\u03bf\u03ba\u03b9\u03bc\u03ce\u03bd \u03b5\u03af\u03bd\u03b1\u03b9 \u03bf \u03c3\u03c5\u03b3\u03ba\u03bb\u03af\u03bd\u03bf\u03bd\u03c4\u03b1\u03c2 \u03c0\u03bf\u03c5 \u03ad\u03c7\u03b5\u03b9 \u03c9\u03c2 \u03ba\u03cd\u03c1\u03b9\u03bf \u03ba\u03b1\u03b8\u03ae\u03ba\u03bf\u03bd \u03c4\u03b7\u03bd \u03b5\u03c0\u03b9\u03c4\u03ac\u03c7\u03c5\u03bd\u03c3\u03b7 \u03c4\u03bf\u03c5 \u03c1\u03b5\u03cd\u03bc\u03b1\u03c4\u03bf\u03c2.<\/p>\n<p>\u03a4\u03bf \u03c3\u03c5\u03b3\u03ba\u03bb\u03af\u03bd\u03bf\u03bd \u03c7\u03c1\u03b7\u03c3\u03b9\u03bc\u03bf\u03c0\u03bf\u03b9\u03b5\u03af\u03c4\u03b1\u03b9 \u03b3\u03b9\u03b1 \u03bd\u03b1 \u03bc\u03b5\u03b9\u03c9\u03b8\u03b5\u03af 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\u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2, \u03b5\u03af\u03bd\u03b1\u03b9 \u03b1\u03c0\u03b1\u03c1\u03b1\u03af\u03c4\u03b7\u03c4\u03bf \u03bd\u03b1 \u03b5\u03b9\u03c3\u03b1\u03c7\u03b8\u03b5\u03af \u03bc\u03b9\u03b1 \u03bf\u03c1\u03b9\u03c3\u03bc\u03ad\u03bd\u03b7<strong> \u03c0\u03bf\u03c3\u03cc\u03c4\u03b7\u03c4\u03b1 \u03b5\u03bd\u03ad\u03c1\u03b3\u03b5\u03b9\u03b1\u03c2<\/strong> \u03c3\u03c4\u03bf \u03c5\u03b3\u03c1\u03cc \u03ba\u03ac\u03b8\u03b5 \u03b4\u03b5\u03c5\u03c4\u03b5\u03c1\u03cc\u03bb\u03b5\u03c0\u03c4\u03bf. \u0395\u03c0\u03bf\u03bc\u03ad\u03bd\u03c9\u03c2, \u03b5\u03af\u03bd\u03b1\u03b9 \u03b1\u03c0\u03b1\u03c1\u03b1\u03af\u03c4\u03b7\u03c4\u03bf \u03bd\u03b1 \u03b5\u03be\u03bf\u03c0\u03bb\u03b9\u03c3\u03c4\u03b5\u03af \u03b7 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1 \u03bc\u03b5 \u03ad\u03bd\u03b1\u03bd \u03b1\u03bd\u03b5\u03bc\u03b9\u03c3\u03c4\u03ae\u03c1\u03b1 \u03c0\u03bf\u03c5 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\u03b5\u03af\u03bd\u03b1\u03b9 \u03bf\u03bc\u03bf\u03b1\u03be\u03bf\u03bd\u03b9\u03ba\u03cc\u03c2 \u03bc\u03b5 \u03c4\u03bf\u03bd \u03b1\u03bd\u03b5\u03bc\u03b9\u03c3\u03c4\u03ae\u03c1\u03b1 \u03ae \u03bc\u03c0\u03bf\u03c1\u03b5\u03af \u03bd\u03b1 \u03b5\u03af\u03bd\u03b1\u03b9 \u03b5\u03be\u03c9\u03c4\u03b5\u03c1\u03b9\u03ba\u03cc\u03c2.<\/p>\n<p><a href=\"https:\/\/www.presticebdt.com\/wp-content\/uploads\/2020\/03\/14.jpg\"><img decoding=\"async\" class=\"aligncenter wp-image-5895\" src=\"https:\/\/www.presticebdt.com\/wp-content\/uploads\/2020\/03\/14.jpg\" alt=\"\u03c0\u03c1\u03bf\u03c0\u03ad\u03bb\u03b1 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2\" width=\"475\" height=\"384\" title=\"\" srcset=\"https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/14-300x243.jpg?lossy=2&amp;strip=1&amp;webp=1 300w, https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/14-495x400.jpg?lossy=2&amp;strip=1&amp;webp=1 495w, https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/14-705x571.jpg?lossy=2&amp;strip=1&amp;webp=1 705w, https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/14-768x622.jpg?lossy=2&amp;strip=1&amp;webp=1 768w, https:\/\/b3469057.smushcdn.com\/3469057\/wp-content\/uploads\/2020\/03\/14.jpg?lossy=2&amp;strip=1&amp;webp=1 845w\" sizes=\"(max-width: 475px) 100vw, 475px\" \/><\/a><\/p>\n<h4>\u0397 \u03c0\u03c1\u03bf\u03c0\u03ad\u03bb\u03b1 \u03c4\u03b7\u03c2 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2.<\/h4>\n<p>\u0397 \u03c0\u03b5\u03c1\u03af\u03c0\u03c4\u03c9\u03c3\u03b7 \u03c4\u03bf\u03c5 <strong>\u03bf \u03b5\u03be\u03c9\u03c4\u03b5\u03c1\u03b9\u03ba\u03cc\u03c2 \u03ba\u03b9\u03bd\u03b7\u03c4\u03ae\u03c1\u03b1\u03c2 \u03b5\u03af\u03bd\u03b1\u03b9 \u03bf \u03ba\u03b1\u03bb\u03cd\u03c4\u03b5\u03c1\u03bf\u03c2, \u03b4\u03b9\u03cc\u03c4\u03b9 \u03b5\u03af\u03bd\u03b1\u03b9 \u03c0\u03b5\u03c1\u03b9\u03c3\u03c3\u03cc\u03c4\u03b5\u03c1\u03bf \u03b8\u03c9\u03c1\u03b1\u03ba\u03b9\u03c3\u03bc\u03ad\u03bd\u03bf\u03c2 \u03ba\u03b1\u03b9 \u03b5\u03c0\u03bf\u03bc\u03ad\u03bd\u03c9\u03c2 \u03c0\u03c1\u03bf\u03ba\u03b1\u03bb\u03b5\u03af \u03bb\u03b9\u03b3\u03cc\u03c4\u03b5\u03c1\u03b5\u03c2 \u03b4\u03b9\u03b1\u03c4\u03b1\u03c1\u03b1\u03c7\u03ad\u03c2 \u03c3\u03c4\u03bf \u03c5\u03b3\u03c1\u03cc<\/strong> (\u03b1\u03c0\u03cc \u03b1\u03ba\u03bf\u03c5\u03c3\u03c4\u03b9\u03ba\u03ae \u03ac\u03c0\u03bf\u03c8\u03b7) \u03bc\u03b5 \u03c4\u03bf \u03bd\u03b1 \u03c4\u03bf \u03b8\u03b5\u03c1\u03bc\u03b1\u03af\u03bd\u03b5\u03b9 \u03b1\u03ba\u03cc\u03bc\u03b7 \u03bb\u03b9\u03b3\u03cc\u03c4\u03b5\u03c1\u03bf. \u039f \u03b1\u03bd\u03b5\u03bc\u03b9\u03c3\u03c4\u03ae\u03c1\u03b1\u03c2 \u03ae \u03bf\u03b9 \u03b1\u03bd\u03b5\u03bc\u03b9\u03c3\u03c4\u03ae\u03c1\u03b5\u03c2 \u03b1\u03c0\u03bf\u03c4\u03b5\u03bb\u03bf\u03cd\u03bd\u03c4\u03b1\u03b9 \u03b1\u03c0\u03cc \u03ad\u03bd\u03b1\u03bd \u03ae \u03bc\u03b9\u03b1 \u03c3\u03b5\u03b9\u03c1\u03ac \u03bf\u03bc\u03bf\u03b1\u03be\u03bf\u03bd\u03b9\u03ba\u03ce\u03bd \u03ae \u03c0\u03bb\u03b5\u03c5\u03c1\u03b9\u03ba\u03ce\u03bd \u03b5\u03bb\u03af\u03ba\u03c9\u03bd- \u03c3\u03c4\u03b9\u03c2 \u03c5\u03c0\u03b5\u03c1\u03b7\u03c7\u03b7\u03c4\u03b9\u03ba\u03ad\u03c2 \u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b5\u03c2 \u03bf\u03b9 \u03ad\u03bb\u03b9\u03ba\u03b5\u03c2 \u03b5\u03af\u03bd\u03b1\u03b9 \u03c0\u03c1\u03b1\u03b3\u03bc\u03b1\u03c4\u03b9\u03ba\u03bf\u03af \u03b1\u03be\u03bf\u03bd\u03b9\u03ba\u03bf\u03af \u03ae \u03c6\u03c5\u03b3\u03bf\u03ba\u03b5\u03bd\u03c4\u03c1\u03b9\u03ba\u03bf\u03af \u03c3\u03c5\u03bc\u03c0\u03b9\u03b5\u03c3\u03c4\u03ad\u03c2- \u03ad\u03c7\u03bf\u03c5\u03bd \u03c9\u03c2 \u03ba\u03cd\u03c1\u03b9\u03bf \u03ba\u03b1\u03b8\u03ae\u03ba\u03bf\u03bd \u03bd\u03b1<strong> \u03bc\u03b5\u03c4\u03b1\u03c6\u03bf\u03c1\u03ac \u03c4\u03b7\u03c2 \u03ba\u03b9\u03bd\u03b7\u03c4\u03b9\u03ba\u03ae\u03c2 \u03b5\u03bd\u03ad\u03c1\u03b3\u03b5\u03b9\u03b1\u03c2 \u03c0\u03bf\u03c5 \u03c0\u03b1\u03c1\u03ad\u03c7\u03b5\u03c4\u03b1\u03b9 \u03b1\u03c0\u03cc \u03c4\u03bf\u03bd \u03ba\u03b9\u03bd\u03b7\u03c4\u03ae\u03c1\u03b1 \u03c3\u03c4\u03bf \u03c1\u03b5\u03c5\u03c3\u03c4\u03cc \u03bc\u03b5 \u03c4\u03b7 \u03bc\u03bf\u03c1\u03c6\u03ae \u03b5\u03bd\u03ad\u03c1\u03b3\u03b5\u03b9\u03b1\u03c2 \u03c0\u03af\u03b5\u03c3\u03b7\u03c2<\/strong>. \u0398\u03b1 \u03c0\u03c1\u03ad\u03c0\u03b5\u03b9 \u03bd\u03b1 \u03c3\u03b7\u03bc\u03b5\u03b9\u03c9\u03b8\u03b5\u03af \u03cc\u03c4\u03b9, \u03b1\u03bd\u03c4\u03af\u03b8\u03b5\u03c4\u03b1 \u03bc\u03b5 \u03c4\u03b7\u03bd \u03ba\u03bf\u03b9\u03bd\u03ae \u03c0\u03b5\u03c0\u03bf\u03af\u03b8\u03b7\u03c3\u03b7, \u03bf \u03b1\u03bd\u03b5\u03bc\u03b9\u03c3\u03c4\u03ae\u03c1\u03b1\u03c2 \u03ae \u03bf \u03c3\u03c5\u03bc\u03c0\u03b9\u03b5\u03c3\u03c4\u03ae\u03c2 \u03c0\u03b1\u03c1\u03ad\u03c7\u03b5\u03b9 \u03ad\u03bd\u03b1 \u03ac\u03bb\u03bc\u03b1 \u03c0\u03af\u03b5\u03c3\u03b7\u03c2 \u03ba\u03b1\u03b9 \u039f\u03a7\u0399 \u03ad\u03bd\u03b1 \u03ac\u03bb\u03bc\u03b1 \u03c4\u03b1\u03c7\u03cd\u03c4\u03b7\u03c4\u03b1\u03c2. \u0397 \u03bc\u03b5\u03c4\u03b1\u03c6\u03bf\u03c1\u03ac \u03b2\u03ad\u03b2\u03b1\u03b9\u03b1 \u03b4\u03b5\u03bd \u03b5\u03af\u03bd\u03b1\u03b9 \u03bf\u03cd\u03c4\u03b5 \u03b1\u03b4\u03b9\u03b1\u03b2\u03b1\u03c4\u03b9\u03ba\u03ae \u03bf\u03cd\u03c4\u03b5 \u03b9\u03c3\u03b5\u03bd\u03c4\u03c1\u03bf\u03c0\u03b9\u03ba\u03ae \u03ba\u03b1\u03b9 \u03b1\u03c5\u03c4\u03cc \u03c3\u03b7\u03bc\u03b1\u03af\u03bd\u03b5\u03b9 \u03cc\u03c4\u03b9 \u03ad\u03bd\u03b1 \u03bc\u03ad\u03c1\u03bf\u03c2 \u03c4\u03b7\u03c2 \u03ba\u03b9\u03bd\u03b7\u03c4\u03b9\u03ba\u03ae\u03c2 \u03b5\u03bd\u03ad\u03c1\u03b3\u03b5\u03b9\u03b1\u03c2 \u03c7\u03ac\u03bd\u03b5\u03c4\u03b1\u03b9 \u03c3\u03b5 \u03b8\u03b5\u03c1\u03bc\u03cc\u03c4\u03b7\u03c4\u03b1.<\/p>\n<h4>\u03a0\u03c1\u03bf\u03c0\u03ad\u03bb\u03b1 \u03ba\u03b1\u03b9 \u03b1\u03bd\u03b5\u03bc\u03b9\u03c3\u03c4\u03ae\u03c1\u03b5\u03c2 \u03b3\u03b9\u03b1 \u03c4\u03bf \u03c3\u03c7\u03b5\u03b4\u03b9\u03b1\u03c3\u03bc\u03cc \u03c4\u03b7\u03c2 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1\u03c2.<\/h4>\n<p>\u039f \u03b1\u03bd\u03b5\u03bc\u03b9\u03c3\u03c4\u03ae\u03c1\u03b1\u03c2 \u03b5\u03af\u03bd\u03b1\u03b9 <strong>\u03c4\u03bf\u03c0\u03bf\u03b8\u03b5\u03c4\u03b5\u03af\u03c4\u03b1\u03b9 \u03ba\u03b1\u03c4\u03ac\u03bd\u03c4\u03b7 \u03c4\u03bf\u03c5 \u03b8\u03b1\u03bb\u03ac\u03bc\u03bf\u03c5 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ce\u03bd \u03c3\u03b5 \u03c0\u03b5\u03c1\u03b9\u03bf\u03c7\u03ae \u03bc\u03b5 \u03c5\u03c8\u03b7\u03bb\u03ae \u03b4\u03b9\u03b1\u03c4\u03bf\u03bc\u03ae \u03b3\u03b9\u03b1 \u03bd\u03b1 \u03bc\u03b5\u03b9\u03c9\u03b8\u03b5\u03af \u03b7 \u03b1\u03c0\u03b1\u03b9\u03c4\u03bf\u03cd\u03bc\u03b5\u03bd\u03b7 \u03b9\u03c3\u03c7\u03cd\u03c2 \u03c4\u03c1\u03bf\u03c6\u03bf\u03b4\u03bf\u03c3\u03af\u03b1\u03c2<\/strong>. \u03a0\u03c1\u03ad\u03c0\u03b5\u03b9 \u03b5\u03c0\u03af\u03c3\u03b7\u03c2 \u03bd\u03b1 \u03c4\u03bf\u03c0\u03bf\u03b8\u03b5\u03c4\u03b5\u03af\u03c4\u03b1\u03b9<strong> \u03cc\u03c3\u03bf \u03c4\u03bf \u03b4\u03c5\u03bd\u03b1\u03c4\u03cc\u03bd \u03c0\u03b9\u03bf \u03bc\u03b1\u03ba\u03c1\u03b9\u03ac \u03b1\u03c0\u03cc \u03c4\u03b7\u03bd \u03b5\u03af\u03c3\u03bf\u03b4\u03bf \u03c4\u03bf\u03c5 \u03b8\u03b1\u03bb\u03ac\u03bc\u03bf\u03c5 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ce\u03bd<\/strong> \u03b1\u03bd\u03ac\u03bb\u03bf\u03b3\u03b1 \u03bc\u03b5 \u03c4\u03b7 \u03b4\u03b9\u03b1\u03b4\u03c1\u03bf\u03bc\u03ae \u03c0\u03bf\u03c5 \u03c0\u03c1\u03ad\u03c0\u03b5\u03b9 \u03bd\u03b1 \u03b4\u03b9\u03b1\u03bd\u03cd\u03c3\u03b5\u03b9 \u03c4\u03bf \u03c5\u03b3\u03c1\u03cc, \u03bf\u03c0\u03cc\u03c4\u03b5 \u03c4\u03bf \u03b9\u03b4\u03b1\u03bd\u03b9\u03ba\u03cc \u03b8\u03b1 \u03ae\u03c4\u03b1\u03bd \u03bd\u03b1 \u03c4\u03bf\u03c0\u03bf\u03b8\u03b5\u03c4\u03b7\u03b8\u03b5\u03af \u03b1\u03ba\u03c1\u03b9\u03b2\u03ce\u03c2 \u03c0\u03af\u03c3\u03c9 \u03b1\u03c0\u03cc \u03c4\u03bf \u03bc\u03bf\u03bd\u03c4\u03ad\u03bb\u03bf. \u03a9\u03c3\u03c4\u03cc\u03c3\u03bf, \u03b1\u03c5\u03c4\u03ae \u03b7 \u03bb\u03cd\u03c3\u03b7 \u03b5\u03af\u03bd\u03b1\u03b9 \u03b4\u03c5\u03c3\u03bc\u03b5\u03bd\u03ae\u03c2, \u03b4\u03b9\u03cc\u03c4\u03b9 \u03c3\u03c4\u03bf \u03c4\u03ad\u03bb\u03bf\u03c2 \u03c4\u03bf\u03c5 \u03b8\u03b1\u03bb\u03ac\u03bc\u03bf\u03c5 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ce\u03bd \u03b7 \u03c4\u03b1\u03c7\u03cd\u03c4\u03b7\u03c4\u03b1 \u03b5\u03af\u03bd\u03b1\u03b9 \u03bc\u03ad\u03b3\u03b9\u03c3\u03c4\u03b7 \u03b3\u03b9\u03b1 \u03b4\u03cd\u03bf \u03ba\u03c5\u03c1\u03af\u03c9\u03c2 \u03bb\u03cc\u03b3\u03bf\u03c5\u03c2: 1) \u03c3\u03c4\u03bf \u03b8\u03ac\u03bb\u03b1\u03bc\u03bf \u03b4\u03bf\u03ba\u03b9\u03bc\u03ce\u03bd \u03bf \u03c3\u03c4\u03cc\u03c7\u03bf\u03c2 \u03b5\u03af\u03bd\u03b1\u03b9 \u03c0\u03ac\u03bd\u03c4\u03b1 \u03bd\u03b1 <strong>\u03ad\u03c7\u03bf\u03c5\u03bd \u03c4\u03b7 \u03bc\u03ad\u03b3\u03b9\u03c3\u03c4\u03b7 \u03c4\u03b1\u03c7\u03cd\u03c4\u03b7\u03c4\u03b1<\/strong>; 2) at the end of the test chamber the boundary layer is thicker than the central area of \u200b\u200bthe test chamber, and this causes a decrease in the effective section seen by the fluid. <strong>\u0391\u03c5\u03c4\u03cc \u03c3\u03b7\u03bc\u03b1\u03af\u03bd\u03b5\u03b9 \u03cc\u03c4\u03b9 \u03b7 \u03c4\u03b1\u03c7\u03cd\u03c4\u03b7\u03c4\u03b1 \u03b5\u03af\u03bd\u03b1\u03b9 \u03b1\u03ba\u03cc\u03bc\u03b7 \u03c5\u03c8\u03b7\u03bb\u03cc\u03c4\u03b5\u03c1\u03b7 \u03b1\u03c0\u03cc \u03cc,\u03c4\u03b9 \u03c3\u03c4\u03b7\u03bd \u03b1\u03c1\u03c7\u03ae \u03c4\u03bf\u03c5 \u03b8\u03b1\u03bb\u03ac\u03bc\u03bf\u03c5 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ce\u03bd.<\/strong>\u03bf \u03b1\u03bd\u03b5\u03bc\u03b9\u03c3\u03c4\u03ae\u03c1\u03b1\u03c2 \u03c4\u03bf\u03c0\u03bf\u03b8\u03b5\u03c4\u03b5\u03af\u03c4\u03b1\u03b9 \u03b5\u03c0\u03bf\u03bc\u03ad\u03bd\u03c9\u03c2 \u03c3\u03c4\u03bf \u03ac\u03ba\u03c1\u03bf \u03c4\u03b7\u03c2 \u03b5\u03ba\u03c4\u03c1\u03bf\u03c0\u03ae\u03c2, \u03cc\u03c0\u03bf\u03c5 \u03b7 \u03c4\u03bf\u03c0\u03b9\u03ba\u03ae \u03c4\u03b1\u03c7\u03cd\u03c4\u03b7\u03c4\u03b1 \u03b5\u03af\u03bd\u03b1\u03b9 \u03c7\u03b1\u03bc\u03b7\u03bb\u03cc\u03c4\u03b5\u03c1\u03b7.<\/p>\n<p>\u0393\u03b9\u03b1 \u03bd\u03b1 \u03b1\u03c0\u03bf\u03c4\u03c1\u03ad\u03c8\u03c9 \u03c4\u03b7\u03bd \u03c0\u03b5\u03c1\u03b9\u03c3\u03c4\u03c1\u03bf\u03c6\u03ae \u03c4\u03b7\u03c2 \u03c1\u03bf\u03ae\u03c2 \u03bc\u03b5\u03c4\u03ac \u03c4\u03b7\u03bd \u03ad\u03bb\u03b9\u03ba\u03b1, \u03ad\u03c7\u03c9 \u03b5\u03c0\u03af\u03c3\u03b7\u03c2<strong> \u03b5\u03b9\u03c3\u03b1\u03b3\u03c9\u03b3\u03ae \u03bb\u03b5\u03c0\u03af\u03b4\u03c9\u03bd \u03c3\u03c4\u03ac\u03c4\u03b7 \u03b3\u03b9\u03b1 \u03c4\u03b7\u03bd \u03b5\u03c5\u03b8\u03c5\u03b3\u03c1\u03ac\u03bc\u03bc\u03b9\u03c3\u03b7 \u03c4\u03bf\u03c5 \u03c1\u03b5\u03cd\u03bc\u03b1\u03c4\u03bf\u03c2<\/strong>.<\/p>\n<p>\u0397 \u03b8\u03ad\u03c3\u03b7 \u03c4\u03b7\u03c2 \u03ad\u03bb\u03b9\u03ba\u03b1\u03c2 \u03c5\u03c0\u03b1\u03b3\u03bf\u03c1\u03b5\u03cd\u03b5\u03c4\u03b1\u03b9 \u03b1\u03c0\u03cc \u03c4\u03b9\u03c2 \u03b5\u03c0\u03b9\u03b4\u03cc\u03c3\u03b5\u03b9\u03c2 \u03ba\u03b1\u03b9 \u03c4\u03bf \u03ba\u03cc\u03c3\u03c4\u03bf\u03c2.<\/p>\n<p>\u039f \u03ba\u03b1\u03bb\u03cd\u03c4\u03b5\u03c1\u03bf\u03c2 \u03c3\u03c5\u03bc\u03b2\u03b9\u03b2\u03b1\u03c3\u03bc\u03cc\u03c2 \u03bc\u03b5\u03c4\u03b1\u03be\u03cd \u03c4\u03b7\u03c2 \u03c4\u03b1\u03c7\u03cd\u03c4\u03b7\u03c4\u03b1\u03c2 \u03c1\u03bf\u03ae\u03c2 \u03b5\u03b9\u03c3\u03cc\u03b4\u03bf\u03c5 \u03ba\u03b1\u03b9 \u03c4\u03b7\u03c2 \u03c4\u03cd\u03c1\u03b2\u03b7\u03c2 \u03c4\u03b7\u03c2 \u03c1\u03bf\u03ae\u03c2 \u03b5\u03af\u03bd\u03b1\u03b9 \u03b7 \u03c4\u03bf\u03c0\u03bf\u03b8\u03ad\u03c4\u03b7\u03c3\u03b7 \u03c4\u03b7\u03c2 \u03ad\u03bb\u03b9\u03ba\u03b1\u03c2 \u03bc\u03b5\u03c4\u03ac \u03c4\u03b7 \u03b4\u03b5\u03cd\u03c4\u03b5\u03c1\u03b7 \u03b3\u03c9\u03bd\u03af\u03b1.<\/p>\n<h3>\u0395\u03c0\u03b5\u03be\u03b5\u03c1\u03b3\u03b1\u03c3\u03af\u03b1 \u03bf\u03c1\u03b9\u03b1\u03ba\u03bf\u03cd \u03c3\u03c4\u03c1\u03ce\u03bc\u03b1\u03c4\u03bf\u03c2 \u03b3\u03b9\u03b1 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ad\u03c2 \u03c3\u03b5 \u03b1\u03b5\u03c1\u03bf\u03b4\u03c5\u03bd\u03b1\u03bc\u03b9\u03ba\u03ae \u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b1 \u03b1\u03c5\u03c4\u03bf\u03ba\u03b9\u03bd\u03ae\u03c4\u03c9\u03bd.<\/h3>\n<p><strong>\u0393\u03b9\u03b1 \u03b1\u03b5\u03c1\u03bf\u03c3\u03ae\u03c1\u03b1\u03b3\u03b3\u03b5\u03c2 \u03b1\u03c5\u03c4\u03bf\u03ba\u03b9\u03bd\u03ae\u03c4\u03c9\u03bd:<\/strong><\/p>\n<p>\u0391\u03c0\u03cc \u03c4\u03b7 \u03c3\u03cd\u03b3\u03ba\u03bb\u03b9\u03c3\u03b7, \u03bc\u03cc\u03bb\u03b9\u03c2 \u03b7 \u03c1\u03bf\u03ae \u03b9\u03c3\u03b9\u03ce\u03c3\u03b5\u03b9 \u03ba\u03b1\u03b9 \u03b7 \u03c4\u03cd\u03c1\u03b2\u03b7 \u03bc\u03b5\u03b9\u03c9\u03b8\u03b5\u03af, \u03c4\u03bf \u03bf\u03c1\u03b9\u03b1\u03ba\u03cc \u03c3\u03c4\u03c1\u03ce\u03bc\u03b1 \u03c3\u03c4\u03bf \u03ba\u03ac\u03c4\u03c9 \u03c4\u03bf\u03af\u03c7\u03c9\u03bc\u03b1 \u03b3\u03b5\u03bd\u03bd\u03b9\u03ad\u03c4\u03b1\u03b9 \u03be\u03b1\u03bd\u03ac \u03c0\u03c1\u03b9\u03bd \u03b5\u03b9\u03c3\u03ad\u03bb\u03b8\u03b5\u03b9 \u03c3\u03c4\u03bf \u03c4\u03bc\u03ae\u03bc\u03b1 \u03b4\u03bf\u03ba\u03b9\u03bc\u03ae\u03c2.<\/p>\n<p>\u0393\u03b9\u03b1 \u03bd\u03b1 \u03b1\u03c0\u03bf\u03c6\u03b5\u03c5\u03c7\u03b8\u03b5\u03af \u03b1\u03c5\u03c4\u03cc \u03c4\u03bf \u03c6\u03b1\u03b9\u03bd\u03cc\u03bc\u03b5\u03bd\u03bf, \u03c7\u03c1\u03b7\u03c3\u03b9\u03bc\u03bf\u03c0\u03bf\u03b9\u03bf\u03cd\u03bd\u03c4\u03b1\u03b9 \u03b4\u03cd\u03bf \u03c3\u03c4\u03c1\u03b1\u03c4\u03b7\u03b3\u03b9\u03ba\u03ad\u03c2:<\/p>\n<p>&#8211;<strong> \u0391\u03bd\u03b1\u03c1\u03c1\u03cc\u03c6\u03b7\u03c3\u03b7 \u03c4\u03bf\u03c5 \u03bf\u03c1\u03b9\u03b1\u03ba\u03bf\u03cd \u03c3\u03c4\u03c1\u03ce\u03bc\u03b1\u03c4\u03bf\u03c2 \u03b1\u03bd\u03ac\u03bd\u03c4\u03b7 \u03c4\u03bf\u03c5 \u03bc\u03bf\u03bd\u03c4\u03ad\u03bb\u03bf\u03c5 \u03bc\u03ad\u03c3\u03c9 \u03bc\u03b9\u03b1\u03c2 \u03c3\u03b5\u03b9\u03c1\u03ac\u03c2 \u03bc\u03b9\u03ba\u03c1\u03ce\u03bd \u03bf\u03c0\u03ce\u03bd<\/strong>.<\/p>\n<p>&#8211; <strong>\u039a\u03b9\u03bd\u03bf\u03cd\u03bc\u03b5\u03bd\u03b7 \u03b6\u03ce\u03bd\u03b7:<\/strong> \u03b4\u03b9\u03ac\u03b4\u03c1\u03bf\u03bc\u03bf \u03c0\u03bf\u03c5 \u03c3\u03b1\u03c2 \u03b5\u03c0\u03b9\u03c4\u03c1\u03ad\u03c0\u03b5\u03b9 \u03bd\u03b1 \u03b1\u03bb\u03bb\u03ac\u03be\u03b5\u03c4\u03b5 \u03c4\u03b7\u03bd \u03bf\u03c1\u03b9\u03b1\u03ba\u03ae \u03c3\u03c5\u03bd\u03b8\u03ae\u03ba\u03b7 \u03c4\u03b7\u03c2 \u03bc\u03b7\u03b4\u03b5\u03bd\u03b9\u03ba\u03ae\u03c2 \u03c4\u03b1\u03c7\u03cd\u03c4\u03b7\u03c4\u03b1\u03c2 \u03c3\u03c4\u03bf\u03bd \u03c4\u03bf\u03af\u03c7\u03bf, \u03b7 \u03bf\u03c0\u03bf\u03af\u03b1 \u03ad\u03c7\u03b5\u03b9 \u03c9\u03c2 \u03b1\u03c0\u03bf\u03c4\u03ad\u03bb\u03b5\u03c3\u03bc\u03b1 \u03bd\u03b1 \u03bc\u03b7\u03bd \u03c3\u03c7\u03b7\u03bc\u03b1\u03c4\u03af\u03b6\u03b5\u03c4\u03b1\u03b9 \u03bf\u03c1\u03b9\u03b1\u03ba\u03cc \u03c3\u03c4\u03c1\u03ce\u03bc\u03b1.<\/p>\n<\/div><\/section>","protected":false},"excerpt":{"rendered":"<p>Let&#8217;s continue the analysis of closed circuit wind tunnel design. We talk about settling chamber, convergent and the requirements of the wind tunnel propeller.<\/p>","protected":false},"author":1,"featured_media":5890,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[33],"tags":[46,45,39,36],"_links":{"self":[{"href":"https:\/\/www.presticebdt.com\/el\/wp-json\/wp\/v2\/posts\/5883"}],"collection":[{"href":"https:\/\/www.presticebdt.com\/el\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.presticebdt.com\/el\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.presticebdt.com\/el\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.presticebdt.com\/el\/wp-json\/wp\/v2\/comments?post=5883"}],"version-history":[{"count":0,"href":"https:\/\/www.presticebdt.com\/el\/wp-json\/wp\/v2\/posts\/5883\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.presticebdt.com\/el\/wp-json\/wp\/v2\/media\/5890"}],"wp:attachment":[{"href":"https:\/\/www.presticebdt.com\/el\/wp-json\/wp\/v2\/media?parent=5883"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.presticebdt.com\/el\/wp-json\/wp\/v2\/categories?post=5883"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.presticebdt.com\/el\/wp-json\/wp\/v2\/tags?post=5883"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}