ÖTEKTİK Al-Si ALAŞIMINDA SOĞUTUCU YÜZEY PÜRÜZLÜLÜĞÜNÜN ARAYÜZEY ISI TRANSFER KATSAYISINA ETKİSİ

Öz

Ara yüzey ısı transfer katsayısının metalden kalıba olan ısı transfer oranı üzerinde önemli rolü vardır. Dökümlerin makro ve mikro yapıları esas olarak ısı transfer oranına bağlıdır. Bu çalışmanın amacı su soğutmalı çelik soğutucu (H13) üzerinde tek yönlü dikey olarak katılaşan ötektik Al-Si alaşımında soğutucu yüzey pürüzlülüğünün ara yüzey ısı transfer katsayısına etkisini incelemektir. Ara-yüzey ısı transfer katsayısı soğutucu yüzey pürüzlülüğüne bağlı olarak, Sonlu Farklar Metoduna dayalı FORTRAN programı ile belirlenmiştir.

 

Sonuç olarak; ısı transfer katsayısı soğutucu yüzey pürüzlülüğü azaldıkça artmıştır, maksimum ısı transfer katsayısı değerleri; 0.15 µm soğutucu yüzey pürüzlülüğünde 3320 W/m²K, 0.22 µm soğutucu yüzey pürüzlülüğünde 3302 W/m²K ve 2.47 µm soğutucu yüzey pürüzlülüğünde 2954 W/m²K olarak elde edilmiştir, ara yüzey ısı transfer katsayıları zamanın güçlü bir fonksiyonu olarak belirlenmiştir, nümerik çözümün hassaslığı Fourier sayısı azaldıkça artmıştır, optimum çözüm hesaplama zamanı göz önünde tutularak Fo=0.0625 ve Dx=0.25 mm ile elde edilmiştir

Anahtar Kelimeler

• Döküm-kalıp arayüzey ısı transfer katsayısı, tek yönlü katılaşma, sonlu farklar metodu.

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