Levent ÇETİN, Mehmet Akif EZAN, Aytunç EREK

Ice thickness measurement method for thermal energy storage unit

Bu çalışmanın amacı, ısıl enerji depolama ünitesindeki katılaşma ara yüzeyinin belirlenmesi için bir ölçüm yönteminin geliştirilmesidir. Faz değişim malzemesinin (FDM) elektriksel iletkenliği katılaşma/erime işleminde önemli oranda değişmektedir. Bu sebeple önerilen ölçüm yöntemi, FDM’nin elektriksel iletkenliğinin gözlenmesini esas almaktadır. Ortam içerisinde birden fazla noktada gözlem yapılabilmesi için özel bir prob tasarlanmış ve ölçüm noktalarından alınan veriler, bir gömülü işlemci vasıtasıyla kaydedilmiş ve bilgisayara aktarılmıştır. Deneysel sonuçlar, geleneksel fotoğraflama yöntemiyle karşılaştırılmıştır. Yöntemin göreceli doğruluğu yaklaşık %3 olarak belirlenmiştir. Bu yöntemin en önemli avantajları, fotoğraflama yönteminde belirli zamanlarda kapağın açılmasından kaynaklanan ısı kazançları yok etmesi ve fotoğraflama yönteminin kullanılamayacağı uygulamalarda, elektronik olarak katılaşma ara yüzeyinin gözlenmesini sağlamasıdır.

Isıl enerji depolama ünitesi için buz kalınlığı ölçüm yöntemi

The aim of this study is to develop a measurement method to determine the solidification front in a thermal energy storage unit. The electrical conductivity of a phase change material (PCM) changes dramatically in solidification/melting process and the proposed measurement method is based on observation of electrical conductivity of PCM. This system utilizes a microprocessor and a multiplexer unit to observe medium via multiple nodes. The experimental results show that the accuracy of this method is nearly 3%, in comparison with the traditional photography method. The most important advantages of this method are elimination of the heat gain, caused by opening a cover in the insulation at specific time periods, compared to the with photography method and ease of observation of solidification fronts electronically which results wider application area where photography method cannot be exploited.

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