Iterative Thermal Design Modelling and Performance Analysis of Superheater-desuperheater System at a Steam Boiler Using Mathcad Software

Öz

In this paper, iterative thermal design model of a superheater-desuperheater system mounted a steam boiler working at pressure of 7.5 bar(g) was completed using Mathcad and findings were interpreted with performance analysis. Aim of the desuperheater (atemperator) in the system is to reduce steam temperature to desired values at superheater outlet. Boiler system having Superheater-desuperheater was also investigated at load cases of %100, %80, %60, %50 and %40, and then, this model was prepared with system scenario containing a superheater without desuperheater in terms of boiler and superheater heat values. As a result of the study, it was determined that desuperheater addition has a positive effect on system heat capacity under proper load cases. Based on the study results, it was commented that superheater-desuperheater addition not only can be used because of construction limitations but can be preferred in order to increase boiler efficiency as well. 

Anahtar Kelimeler

• Desuperheater,mathcad thermal design,superheater

Bir Buhar Kazanındaki Kızdırıcı – Atemperatör Sisteminin Mathcad Yazılımı ile İteratif Isıl Tasarım Modellemesi ve Performans Analizi

Öz

Bu çalışmada, 7,5 bar(g) çalışma basıncına sahip bir buhar kazanına monte edilen bir kızdırıcı-atemperatör sisteminin iteratif ısıl tasarım modeli Mathcad yazılımı ile gerçekleştirilmiş ve elde edilen bulgular performans analizi ile yorumlanmıştır. Atemperatörün sistemdeki görevi kızdırıcı çıkışı buhar sıcaklığını istenilen sıcaklığa düşürmektir. Kızdırıcı-Atemperatör ikilisine sahip kazan sistemi; %100, %80, %60, %50 ve %40 yük koşulları altında incelenen bu sistem, atemperatörsüz bir kızdırıcıya sahip kazan sistemiyle de kazan ve kızdırıcı ısı kapasitesi açısından karşılaştırılmıştır. Bu çalışmalar sonucunda atemperatör eklentisinin, sistem ısı kapasitesine doğru yük şartları uygulandığında olumlu etki gösterdiği belirlenmiştir. Çalışma verilerine dayanarak, doğru yük şartları altındaki kızdırıcı-atemperatör eklentisinin yalnızca konstrüksiyon kısıtlamaları nedeniyle değil, aynı zamanda kazan verimini arttırmak amacıyla da kullanılabileceği yorumu yapılmıştır.

Anahtar Kelimeler

• Atemperatör,Mathcad Isıl Tasarım,Kızdırıcı

Kaynakça

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