Investigation of Outdoor Air Temperature Effects on Heat Recovery in Cross Flow Heat Exchanger

Year 2023, , 571 - 589, 31.08.2023

Ramazan Selver

https://doi.org/10.18185/erzifbed.1327981

Abstract

A heat recovery device was designed and manufactured to provide air-to-air heat transfer by using a cross-flow heat exchanger on the pipe bundles. For this purpose, different cold air inlet temperature values and the temperature values of high temperature hot exhaust gases in the tube bundle heat exchanger were determined as operating parameters. According to the temperature increase of the cold air entering the heat exchanger; The kinematic viscosity values of the air increased and the maximum Reynolds number in the flow state of the air passing through the test heat exchanger was decreased. The average Nusselt numbers and average air convection coefficients in the flow of air decreased according to the temperature increase of the cold air. According to the temperature increase of the cold air entering the heat exchanger, both the analytical and experimental outlet temperature values of the cold air leaving the heat exchanger increase very close to each other. With this increase, the amount of heat transferred from the fluid to the fluid in the heat exchanger decreases. While the temperature value of the cold air entering the heat exchanger increases, the temperature difference value of the advancing air from the beginning to the outlet (ΔT= Ts – Ti) decreases. Due to this decrease, a decrease was observed in the amount of heat transfer.

Keywords

cross-flow heat exchanger, heat recovery, industrial waste heat, pipe bundles

References

• [1] Nurettin YAMANKARADENİZ, Salih ÇOŞKUN, Muhittin CAN 2007. Uludağ Üniversitesi Mühendislik- Mimarlık Fakültesi Dergisi Cilt:12, Sayı:1.
• [2] Lazzorin, R. M. 1998. “Heat Pump in Industry Equipment”, Heat Recorvey Sistem, Chp, 14(6), Pages 581-597.
• [3] KOCABAŞ, C. 2014. “Farklı Malzemelerden İmal Edilmiş Plakalı Isı Değiştiricilerinin Atık Geri kazanımı Performanslarının Deneysel Analizi”, YL Tezi, Bilecik Şeyh Edebali Üniversitesi, FBE, Makine-İmalat Mühendisliği ABD, Bilecik.
• [4] Tarakcıoğlu, A. 2006. “Sanayide Atık Isıdan Yararlanma Yöntemleri”, YL Tezi, Yıldız Teknik Üniversitesi FBE, İstanbul.
• [5] Mebratu Yisahak, Dr. Edessa Dribssa, Mukesh Didwania, 2017. “Waste Heat Recovery Analysis: An Overview of Reversed Heat Pump Systems”, International Journal of Scientific & Engineering Research, vol. 8(5), pp. 1552-1557.
• [6] Kevin Nnanye Nwaigwe, 2019. “Waste Heat Recovery Analysis: An Overview of Reversed Heat Pump Systems”, American Journal of Mechanical Engineering and Automation. vol. 6(1), pp. 9-13.
• [7] Owen M. S. 2007. “Isıtma Havalandırma ve İklimlendirme Uygulamaları” ASHRAE Türk Tesisat Mühendisleri Derneği, İstanbul.
• [8] Frank P. Incropera & David P. DeWitt 2000. “Isı ve Kütle Geçişinin Temelleri”, Literatür Yayınları, 4. Baskı, İstanbul.
• [9] Grimison, E. D. 1937. “Correlation and Utilization of New Data on Flow Resistance and Heat Transfer for Crossflow of Gases Over Tube Banks”, Trans. A.S.M.E., vol. 59, pp. 583-594.
• [10]Whitaker, S. 1972. “Forced convection heat transfer correlations for flow in pipes, past flat plates, single cylinders, single spheres, and for flow in packed beds and tube bundles”, AIHChE J., vol. 18(2), Page 361-371.
• [11]Zhukauskas, A. and Ulinskas, R. 1988. “Heat Transfer from Tubes in Crossflow”, United State, N. P.