Çarpan Eş Eksenli Bir Hava Jetinde Debi Oranının Akış Karakteristikleri Üzerine Etkisinin Deneysel Olarak İncelenmesi

Year 2018, Volume: 8 Issue: 2, 239 - 248, 31.07.2018

Burak Markal

https://doi.org/10.17714/gumusfenbil.340800

Abstract

Bu çalışmada, dairesel ve halkasal
eş eksenli akış pasajlarına sahip bir lüleden çıkarak dairesel bir plaka
üzerine çarpan jetin hidrodinamik karakteristikleri deneysel olarak
incelenmiştir. Deneyler üç farklı Reynolds sayısında (Re = 6688, 9364 ve 12039),
beş farklı debi oranında (Q* = 0, 0.2, 0.5, 0.8 ve 1.0) ve tek bir boyutsuz
lüle-plaka uzaklığında (H* = 0.8) gerçekleştirilmiştir. Belirtilen çalışma
parametreleri için boyutsuz basınç katsayısının (C_P) çarpma plakası
üzerinde merkez hattı boyunca dağılımı elde edilmiştir. İncelenen tüm Reynolds
sayılarında, Q* = 0, 0.2 ve 0.5 değerleri için durma noktası çarpma plakası
merkezinde oluşmakta ve ilgili noktaya ait basınç değerleri artan Q* ile
azalmaktadır. Q* = 0.8 ve 1.0 ise birbirine benzer davranış göstermekte olup,
bu şartlar altında çoklu durma noktaları oluşmaktadır.  

Keywords

Basınç dağılımı, Debi oranı, Eş eksenli çarpan jet

Experimental Investigation of the Effect of Flow Rate Ratio on the Flow Characteristics in a Co-axial Impinging Air Jet

Abstract

In this study, hydrodynamic characteristics of a
jet issuing from a nozzle with concentric circular and annular flow passages are
investigated experimentally. Experiments are conducted for different Reynolds
number (Re = 6688, 9364 and 12039) and flow rate ratio (Q* = 0, 0.2, 0.5, 0.8 and
1.0) at a constant dimensionless nozzle-to-plate distance (H* = 0.8). For the
relevant test parameters, the distribution of the dimensionless pressure
coefficient (C_P) through the centerline of the impingement plate is
obtained. For all the Reynolds numbers and the values of Q* = 0, 0.2 and 0.5,
the stagnation point formed at the center of the impingement plate, and the
relevant pressure values for this point decreases with increasing Q*. On the
contrary, Q* = 0.8 and 1.0 shows similar behaviors (for each other) in which
multiple stagnation points occur.           

Keywords

Pressure distribution, Flow rate ratio, Co-axial impinging jet

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