Yüksek sıcaklıklı sinterleme fırınında sıcaklık dağılımının sayısal olarak modellenmesi

Öz

Yüksek enerji tüketiminin olduğu ve genelde geleneksel reçeteler ile sürdürülen sinterleme prosesleri için yeni enerji yönetim sistemlerinin geliştirilmesi günümüzde önemli bir araştırma konusu haline gelmiştir. Sinterleme işleminde kullanılan fırın içerisinde homojen bir sıcaklık dağılımı için sayısal modellemeler üzerine yoğunlaşılmıştır. Sıcaklık farkının yüksek olduğu durumlarda fırın içerisinde bulunan malzemelerin iç yapısı ciddi değişiklikler gösterebilmektedir. Bu çalışmada oda sıcaklığından 1100 °C sıcaklığa kadar zamana bağlı bir sayısal tasarım ve analiz gerçekleştirilmiştir. 1070x1580x1030 mm boyutlarındaki fırın içerisinde farklı konumlara yerleştirilen numunelerin zamana bağlı olarak sıcaklık değişimleri sayısal olarak incelenmiştir. Sayısal çalışmalarda başlangıç koşulları olarak oda sıcaklığı ve başlangıç fırın sıcaklığı tanımlanmıştır. Sınır şartları olarak ise ısıtıcı yüzeylerinde ısı akısı ve fırın dışında taşınım olarak verilmiştir. Sayısal hesaplamalar sonunda zamana bağlı olarak fırın içerisinde ve numunelerin üzerinde sıcaklık değerleri bulunmuştur. Zamana bağlı olarak numuneler arasındaki sıcaklık farkları başlangıçta beklenildiği gibi yüksek ancak kararlı hale gelindiğinde bu farkların 17 °C’ye kadar düştüğü gözlemlenmiştir. Literatürdeki çalışmalardan farklı olarak numunelerin doğrudan ışınım etkisi altında olmayıp korunaklı bir hazne içerisindeki durumu incelenmiş, sıcaklık farklarının 2 °C kadar düştüğü görülmüştür. İki farklı durum için yapılan analizde zamana bağlı sıcaklık dağılımları ve sıcaklık farkları karşılaştırmalı olarak verilmiştir.

Anahtar Kelimeler

• Yüzeyden yüzeye radyasyon
• HAD
• Sinterleme fırını
• Zamana bağlı ısıl analiz

Numerical modeling of temperature distribution in a high temperature sintering furnace

Abstract

The development of new energy management systems for sintering processes with high energy consumption and generally carried out with traditional recipes has become an important research topic nowadays. It has been focused on homogeneous temperature distribution in the furnace used in the sintering process. If the temperature difference is high in the furnace, the internal structure of the materials can show serious changes. In this study, transient numerical design and analysis were carried out from room temperature to 1100 °C. The temperature changes of the samples placed at different locations in the furnace with the dimensions of 1070x1580x1030 mm were numerically investigated as transiently. In numerical studies, room temperature and initial furnace temperature were defined as the initial conditions. The boundary conditions are given as heat flux on the heater surfaces and convection outside the furnace. At the end of numerical solutions, temperature values were found inside the furnace and on the samples transiently. It was showed that the temperature differences between the samples were high that is expected at the beginning, but these differences decreased to about 17 °C in the steady conditions. Unlike the studies in the literature, the condition of the samples in a protected chamber, not under the influence of direct radiation, was examined and it was observed that the temperature differences decreased by up to 2 °C. In the analysis, time-dependent temperature distributions and temperature differences are given comparatively for two different cases.

Keywords

• S2S radiation
• CFD
• Sintering furnace
• Unsteady thermal analysis

Kaynakça

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