Experımental Investigation of Heat Transfer Characteristics in Unconfined and Confıned Impinging Jet Arrays with 45° Inclined Secondary Jets

Haluk Keleş; Yücel Özmen

Article Details

Experımental Investigation of Heat Transfer Characteristics in Unconfined and Confıned Impinging Jet Arrays with 45° Inclined Secondary Jets

Authors:

Haluk Keleş | Yücel Özmen

Publisher:

Cukurova University

Main Topics:

Makine Mühendisliği (Diğer)

Journal:

Çukurova Üniversitesi Mühendislik Fakültesi Dergisi Vol.39 Issue 4, pp.923-937

Document Type:

Article

Publication Date:

12/2024

Document Language:

Turkish

Document ID (Org No.):

2001335471

pISSN:

2757-9255

Keywords:

Abstract:

 In this study, the heat transfer effects at the impingement surface in unconfined and confined impinging array jet flows with 45 inclined secondary jets are experimentally investigated. In the unconfined and confined jet flow fields, temperature distributions were obtained with a thermal camera along the center axis of the impingement plate for 20000 and 30000 values of the Reynolds number and 0,5, 1, 3 and 6 values of the nozzle-to-plateinter-plate spacing. From the obtained temperature distributions, the effect of Reynolds number, nozzle-to-plateinter-plate spacing and the presence of a confinement plate on the Nusselt distributions on the impingement plate were investigated. In both unconfined and confined cases, the Nusselt values on the impingement plate increase with increasing Reynolds number and decrease with increasing nozzle-to-plateinter-plate spacing. At the stagnation point on the impingement plate in the direction of the axis of the primary nozzle and at the position of the impingement plate in the direction of the axes of the secondary jets, the local Nusselt number takes peak values. The peaks on the impingement plate become sharper as the Reynolds number increases. The positions of the peaks formed by the secondary jets on the impingement plate shift to larger rD values with increasing nozzle-to-plateinter-plate spacing. The presence of a confinement plate in the flow fields reduces the Nusselt values on the impingement plate.

 In this study, the heat transfer effects at the impingement surface in unconfined and confined impinging array jet flows with 45 inclined secondary jets are experimentally investigated. In the unconfined and confined jet flow fields, temperature distributions were obtained with a thermal camera along the center axis of the impingement plate for 20000 and 30000 values of the Reynolds number and 0,5, 1, 3 and 6 values of the nozzle-to-plateinter-plate spacing. From the obtained temperature distributions, the effect of Reynolds number, nozzle-to-plateinter-plate spacing and the presence of a confinement plate on the Nusselt distributions on the impingement plate were investigated. In both unconfined and confined cases, the Nusselt values on the impingement plate increase with increasing Reynolds number and decrease with increasing nozzle-to-plateinter-plate spacing. At the stagnation point on the impingement plate in the direction of the axis of the primary nozzle and at the position of the impingement plate in the direction of the axes of the secondary jets, the local Nusselt number takes peak values. The peaks on the impingement plate become sharper as the Reynolds number increases. The positions of the peaks formed by the secondary jets on the impingement plate shift to larger rD values with increasing nozzle-to-plateinter-plate spacing. The presence of a confinement plate in the flow fields reduces the Nusselt values on the impingement plate.

 In this study, the heat transfer effects at the impingement surface in unconfined and confined impinging array jet flows with 45 inclined secondary jets are experimentally investigated. In the unconfined and confined jet flow fields, temperature distributions were obtained with a thermal camera along the center axis of the impingement plate for 20000 and 30000 values of the Reynolds number and 0,5, 1, 3 and 6 values of the nozzle-to-plateinter-plate spacing. From the obtained temperature distributions, the effect of Reynolds number, nozzle-to-plateinter-plate spacing and the presence of a confinement plate on the Nusselt distributions on the impingement plate were investigated. In both unconfined and confined cases, the Nusselt values on the impingement plate increase with increasing Reynolds number and decrease with increasing nozzle-to-plateinter-plate spacing. At the stagnation point on the impingement plate in the direction of the axis of the primary nozzle and at the position of the impingement plate in the direction of the axes of the secondary jets, the local Nusselt number takes peak values. The peaks on the impingement plate become sharper as the Reynolds number increases. The positions of the peaks formed by the secondary jets on the impingement plate shift to larger rD values with increasing nozzle-to-plateinter-plate spacing. The presence of a confinement plate in the flow fields reduces the Nusselt values on the impingement plate.

 Bu çalışmada, 45 eğimli ikincil jetlere sahip sınırlandırılmamış ve sınırlandırılmış çarpan dizi jet akışlarında çarpma yüzeyindeki ısı transferi etkileri deneysel olarak incelenmiştir. Sınırlandırılmamış ve sınırlandırılmış jet akış alanlarında, Reynolds sayısının 20000 ve 30000 değerleri ve lüle-levhalevhalar arası açıklığın 0,5, 1, 3 ve 6 değerleri için çarpma levhasının orta ekseni boyunca termal kamera ile sıcaklık dağılımları elde edilmiştir. Elde edilen sıcaklık dağılımlarından, Reynolds sayısının, lüle-levhalevhalar arası açıklığın ve sınırlayıcı levha varlığının çarpma levhası üzerindeki Nusselt dağılımlarına etkisi araştırılmıştır. Hem sınırlandırılmamış hem de sınırlandırılmış durumda, çarpma levhası üzerindeki Nusselt değerleri artan Reynolds sayısı ile artmakta, artan lüle-levhalevhalar arası açıklıkla azalmaktadır. Çarpma levhası üzerinde birincil lüle ekseni doğrultusundaki durma noktasında ve ikincil jetlerin eksenleri doğrultusundaki çarpma levhası konumlarında yerel Nusselt sayısı pik değerler almaktadır. Çarpma levhası üzerinde oluşan pikler, Reynolds sayısı arttıkça daha keskin hale gelmektedir. İkincil jetlerin çarpma levhası üzerinde oluşturdukları piklerin konumları artan lüle-levhalevhalar arası açıklı ile daha büyük rD değerlerine kaymaktadır. Akış alanlarında sınırlayıcı levhanın varlığı, çarpma levhası üzerindeki Nusselt değerlerini azaltmaktadır.

Article Details

Experımental Investigation of Heat Transfer Characteristics in Unconfined and Confıned Impinging Jet Arrays with 45° Inclined Secondary Jets

Authors:

Haluk Keleş | Yücel Özmen

Publisher:

Cukurova University

Main Topics:

Makine Mühendisliği (Diğer)

Journal:

Çukurova Üniversitesi Mühendislik Fakültesi Dergisi Vol.39 Issue 4, pp.923-937

Document Type:

Article

Publication Date:

12/2024

Document Language:

Turkish

Document ID (Org No.):

2001335471

pISSN:

2757-9255

Impinging jet array

Inclined secondary jet

Unconfined jet

Confined jet

Nusselt number distributionÇarpan dizi jet

Eğimli ikincil jet

Sınırlandırılmamış jet

Sınırlandırılmış jet

Nusselt sayısı dağılımı

Issues

Article Details

Authors: Haluk Keleş | Yücel Özmen

Publisher: Cukurova University

Main Topics: Makine Mühendisliği (Diğer)

Journal: Çukurova Üniversitesi Mühendislik Fakültesi Dergisi Vol.39 Issue 4, pp.923-937

Document Type: Article

Publication Date: 12/2024

Document Language: Turkish

Document ID (Org No.): 2001335471

pISSN: 2757-9255

Issues

Authors:

Haluk Keleş | Yücel Özmen

Publisher:

Cukurova University

Main Topics:

Makine Mühendisliği (Diğer)

Journal:

Çukurova Üniversitesi Mühendislik Fakültesi Dergisi Vol.39 Issue 4, pp.923-937

Document Type:

Article

Publication Date:

12/2024

Document Language:

Turkish

Document ID (Org No.):

2001335471

pISSN:

2757-9255