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Journals / Politeknik Dergisi / 2018 / Cilt: 21 - Sayı: 1

Modeling of Cross Flow Air-Gas Heat Exchanger Using Finite Difference Method

Çapraz Akışlı Hava-Gaz Isı Değiştiricisinin Sonlu Farklar Metodu Kullanılarak Modellenmesi

HALİL ATALAY
M. Turhan ÇOBAN
Pages
155–163
DOI
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

For example, the temperature profile of a hot air with an inlet temperature of 75 C and the temperature profile of a cold air with an inlet temperature of 20 C were calculated with the aid of the mathematical model and the total heat transfer was determined approximately 45,5 KW.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:In this study, temperature distribution and total heat transfer were calculated for two-dimensional cross flow heat exchanger using finite difference method.
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Key Findings & Data:Air and exhaust gases were taken as hot fluid, thus the performance of the heat exchanger was examined.
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Conclusion & Impact:For example, the temperature profile of a hot air with an inlet temperature of 75 C and the temperature profile of a cold air with an inlet temperature of 20 C were calculated with the aid of the mathematical model and the total heat transfer was determined approximately 45,5 KW.
🔬Design:Modeling & Simulation
📍Scope:Comprehensive Sample
⚙️Variables:Isı transferi · sonlu farklar metodu · sıcaklık dağılımı

Abstract

In this study, temperature distribution and total heat transfer were calculated for two-dimensional cross flow heat exchanger using finite difference method. A cross- flow heat exchanger consists of parallel sheets. While the hot fluid flows from one plate, the cold fluid flows through the next plate with cross geometry. This structure is repeated in many plates. After the differential equation is converted to the finite difference equation, it proceeds in a row by starting from the corner where the two inlet temperatures are known, and thus the temperature profile of the entire heat exchanger is easily reached. Throughout the study, air was used as cold fluid in all analysis. Air and exhaust gases were taken as hot fluid, thus the performance of the heat exchanger was examined. A mathematical model was developed by using the finite difference equations in Java programming language. For example, the temperature profile of a hot air with an inlet temperature of 75 C and the temperature profile of a cold air with an inlet temperature of 20 C were calculated with the aid of the mathematical model and the total heat transfer was determined approximately 45,5 KW.

Özet

Bu çalışmada çapraz (dik) akışlı ısı değiştiricileri üzerindeki sıcaklık dağılımı ve ısı transferi hesapları iki boyutlu sonlu farklar modeli kullanılarak yapılmıştır. Çapraz akışlı ısı değiştiricileri birbirine paralel levhalardan oluşur ve bir levhadan sıcak akışkan akarken bir sonraki levhadan soğuk akışkan çapraz geometride akar. Bu yapı birçok levha halinde tekrarlanır. Diferansiyel denklem sonlu farklar denklemi haline getirildikten sonra iki giriş sıcaklığının bilindiği köşeden başlamak suretiyle satırlar halinde çözülerek ilerlenir ve bu şekilde tüm ısı değiştiricinin sıcaklık profiline kolaylıkla ulaşılır. Bu çalışma boyunca soğuk akışkan olarak tüm analizlerde hava alınmıştır. Sıcak akışkan olarak ise hava ve yanma gazları alınarak ısı değiştiricinin performansı incelenmiştir. Bu çalışma için sonlu fark denklemleri kullanılarak Java programlama dilinde bir matematiksel model geliştirilmiştir. Örnek olarak 750C giriş sıcaklığına sahip sıcak akışkan ile 200C giriş sıcaklığına sahip soğuk akışkanın sıcaklık profili geliştirilen matematiksel model yardımı ile adım adım hesaplanmış ve toplam ısı transfer değeri de yaklaşık 45,5 KW olarak belirlenmiştir.

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Cite This Article

ATALAY, H., ÇOBAN, M. T. (2018). Modeling of Cross Flow Air-Gas Heat Exchanger Using Finite Difference Method. Politeknik Dergisi, Cilt: 21 - Sayı: 1, 155–163. https://ajindex.com/articles/307553

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References (15)

  1. Abraham, J.P., Sparrow, E.M. Tong, J.C.K., “Heat transfer in all pipe flow regimes: laminar, transitional/intermittent and turbulent”, International Journal of Heat and Mass Transfer, 52: 557–563, (2009)
  2. Cadavid Y., Amell A., Cadavid F., “ Heat transfer model in recuperative compact heat exchanger type:experimental and numerical analysis”, Applied Thermal Engineering, 50-56, (2013)
  3. Çengel, Y.A., “Isı ve Kütle Transferine Pratik Bir Yaklaşım”, 3.Basım, Güven Kitabevi, İzmir.(2011)
  4. Çoban, M.T., “İdeal gazların termodinamik ve termofiziksel özelliklerinin modellenmesi”, 17. Isı Bilimi ve Tekniği Kongresi, 24-27 Haziran (2009), Cumhuriyet Üniversitesi, Sivas
  5. Çoban, M. T., “Sürekli kanatlı, zorlanmış taşınımlı hava su ısı değiştiricinin modellenmesi”, ULIBTK’ 13-19. Ulusal Isı Bilimi ve Tek. Kongresi, Samsun, (2013)
  6. Gnielinski V., “New equations for heat and mass transfer in turbulent pipe and channel flow”, Int. Chem. Eng. 16: 359–367, (1976)
  7. Goudar, C.T. and Sonnad, J.R., “Comparison of the iterative approximations of the Colebrook-White equation”, Hydrocabon Processing, pp 79-83, (2008)
  8. Hajabdollahi, H., Seifoori S., “Effect of flow maldistribution on the optimal design of a cross flow heat exchanger”, Int. J. Therm. Sci., 109: 242- 252, (2016)
  9. Incropera,F.P., Dewitt,D.P., “Isı ve Kütle Geçişinin Temelleri”,7. Basım, Palme Yayıncılık, Ankara, (2015)
  10. Liu, P., Nasr, M.R., Ge, G., Alonso, M.J., Mathisen, H.M., Fathieh, F., Simonson, C., “A theoretical model to predict frosting limits in cross-flow air-to-air flat plate heat/energy exchangers”, Energy and Buildings, 110: 404-414, (2016)
  11. Navarro H.A., Cabezas-Gomez L.C., “Effectiveness-NTU computation with a mathematical model for cross-flow heat exchangers”, Brazilian Journal of Chemical Engineering, Vol.:24, No:04, PP.:509-521, ISSN 0104-6632, (2007)
  12. Oğulata R.T., Doba F., Yılmaz T., “Irreversibility analysis of cross-flow heat exchangers”, Energy Conversion & Management, 1585-1599, (2000)
  13. Rogiers F., Stevens T., Baelmans M., “Optimal recuperator design for use in a micro gas turbine”, The Sixth International Workshop on Micro and Nanotechnology for Power Generation and Energy Conversion Applications, Berkeley, U.S.A, (2006)
  14. Quadir,G.A., Badruddin, I.A., Ahmed, N.J.S., “Numerical investigation of the performance of a triple concentric pipe heat exchanger”, Int. J. Heat Mass Transf., 75:165-172, (2014)
  15. Saha, K.S., Baelmans, M., “A de