Süperhidrofobik ve hidrofobik yüzeyler üzerinde sıvı damlası gaz kabarcığı ve sıvı jeti dinamiğinin incelenmesi

Öz

Bu çalışmada, hidrofobik ve süperhidrofobik yüzeylerin hidrofilik yüzeylerden farklılıkları ve bu yüzeyler üzerinde sıvı damlası, gaz kabarcığı ve sıvı jeti dinamiği incelenmiştir. Hidrofobik yüzeyler üzerinde sıvı/su damlası yüksek temas açısı ile durmasına karşılık gaz/hava kabarcığı yüzeyde yayılmaktadır. Süperhidrofobik yüzeyler için Cassie ve Wenzel olmak iki farklı durum mevcuttur. Her iki durumda da yüzeyin temas açısı yüksek olmasına karşılık Cassie durumda temas açısı histerezisi düşük Wenzel durumda ise yüksek olmaktadır. Cassie durum süperhidrofobik yüzeyler üzerindeki sıvı damlası yüzeyle çok az noktalardan temas etmesi sayesinde küçük bir dış kuvvet etkisiyle yüzeyden uzaklaştırılabilmektedir. Süperhidrofobik yüzeyler sıvı içerisine daldırıldıklarında etrafı ince bir hava filmi ile kaplanmaktadır. Bu şekildeki yüzeye alttan gönderilen hava kabarcığı yüzeydeki hava filmine nüfuz ederek kaybolmaktadır. Yüzey üzerindeki kabarcık ise yüzeyde yayılmaktadır. Süperhidrofobik yüzeyler donma/buzlanmasının önlenmesi, film/damla yoğuşmanın kontrolü, kaynamada oluşan hava kabarcık dinamiğinin kontrolü gibi birçok alanlarda uygulama alanları bulunmaktadır.

Anahtar Kelimeler

• Süperhidrofobik yüzey,Temas açısı,Temas açısı histerezisi,Sıvı jeti,Sıvı damlası,Gaz kabarcığı

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