Silindirik enjeksiyon deliklerinde film soğutma incelemesi

Bu makale, düz bir plaka üzerinde film soğutmanın deneysel ve sayısal olarak incelenmesiyle ilgilidir. Deneysel ve sayısal olarak incelenen modelde 8.5 mm çapında, silindirik kesitli, onbir enjeksiyon deliği, tek sıralı olarak kullanılmıştır. Enjeksiyon açısı 30° dir. Üfleme oranı film soğutmasında etkilidir. Bu etkileri incelemek için 57 °C enjeksiyon sıcaklığında ve farklı üfleme oranlarında deneyler yapılmıştır. Deneysel ve sayısal sonuçlar bize, film soğutma etkenliğini üfleme oranının etkilediğini ve mevcut seçilen üfleme oranları içinde 0.5 üfleme oranında etkenliğin en iyi olduğunu göstermiştir. Ayrıca üfleme oranları artırıldığında film soğutma etkenliğinin azaldığı görülmüştür.

Investigation of film cooling on cylindrical injection holes

This paper deals with experimental and numerical investigation of the film cooling effectiveness on a flat plate. Eleven injection holes on the model are in a single row. The holes have cylindrical cross section and they are 8.5 mm diameters. The injection angle is 30°. The blowing ratios vary from 0.5 to 2.0. The experiments and their computational models have been established to investigate their effects at 57 °C injection temperature and different blowing ratios. . The experimental and computational solutions show the blowing ratio affect on film cooling effectiveness and a suitable blowing ratio should be selected for good film cooling performance in both mainstream and lateral direction. In the current study, the best blowing ratio is 0.5. In additon, when the blowing ratio is increased the film cooling effectiveness deacreases.

Kaynakça

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