أرسل هذا في رسالة قصيرة: Visualization of counter-rotating streamwise vortices in a rectangular channel with one-sided wavy surface

  ______     ___      ______    _____     ______  
 /_   _//   / _ \\   /_____//  |  ___||  /_   _// 
 `-| |,-   | / \ ||  `____ `   | ||__    `-| |,-  
   | ||    | \_/ ||  /___//    | ||__      | ||   
   |_||     \___//   `__ `     |_____||    |_||   
   `-`'     `---`    /_//      `-----`     `-`'   
                     `-`