Isı Bilimi ve Tekniği Dergisi 1300-3615 2667-7725 Türk Isı Bilimi ve Tekniği Derneği Experimental Methods in Fluid Flow, Heat and Mass Transfer Turbulent Flows Akışkan Akışı, Isı ve Kütle Transferinde Deneysel Yöntemler Türbülanslı Akışlar İçine bakır borular yerleştirilmiş vakumlu tüplü güneş enerjili hava ısıtıcısının termal performansı Thermal performance of an evacuated tube solar air heater inserted with copper tubes https://orcid.org/0000-0001-9554-3988 Adaikalasamy Veerakumar Coimbatore Institute of Engineering and Technology https://orcid.org/0000-0003-3369-4750 T Karthickmunisamy Coimbatore Institute of Engineering and Technology R Venkatramanan Suguna College of Engineering S Vijayan Coimbatore Institute of Engineering and Technology https://orcid.org/0009-0001-4557-1213 R Parthiban Coimbatore Institute of Engineering and Technology https://orcid.org/0000-0001-8881-6685 S Ram Kumar Hindusthan College of Engineering and Technology Coimbatore K Karthi Sri Sai Ranganathan Engineering College https://orcid.org/0009-0002-4960-1221 V Hari Ganesh RVS College of Engineering and Technology 05 01 2026 46 1 156 166 11 22 2025 04 09 2026 Copyright © 1977, Isı Bilimi ve Tekniği Dergisi 1977 Isı Bilimi ve Tekniği Dergisi

Bu çalışmada bakır borulu kelebek vakumlu borulu güneş enerjili hava ısıtıcısının (BETSAH-CT) performansı araştırılmıştır. Deneysel analiz 10 ila 50 kg/saat arasında değişen hava akış hızlarında gerçekleştirilmiştir. CT konfigürasyonunun çıkış sıcaklığı, termal ve efektif verimlilikler, ısı kazancı ve basınç düşüşü üzerindeki etkisi incelenmiştir. BETSAH-CT, 10 kg/saat'te 110,1 °C'lik maksimum çıkış hava sıcaklığına ve 10 kg/saat'te 89,7 °C'lik ortalama sıcaklığa ulaşmıştır. En yüksek faydalı ısı kazancı 50 kg/saat'te 663,8 W olarak kaydedilmiştir. Termal verimlilik hava akış hızıyla artmış ve 50 kg/saat'te %54,2'lik bir anlık tepe verime ulaşmıştır. Basınç düşüşü ve pompalama gücü hususları hava akışının ideal sistem performans oranını ön plana çıkarmaktadır. Ekserji verimliliği eğilimleri güneş ışınımı eğilimlerine neredeyse benzerdir ve ekserji verimliliğinin en yüksek değerleri akış hızıyla azalmaktadır. Sonuçlar, BETSAH-CT tasarımının termal verimliliği ve ısı kazanımını iyileştirme avantajına sahip olduğunu ve bu sayede güneş enerjisiyle hava ısıtmada sürdürülebilir ve enerji açısından verimli bir çözüm olarak kullanılabileceğini göstermektedir.

This study investigates the performance of butterfly evacuated tube solar air heater with copper tubes (BETSAH-CT). The experimental analysis was conducted in across varying air flow rates ranging from 10 to 50 kg/h. The effect of CT configuration on outlet temperature, thermal and effective efficiencies, heat gain and pressure drop was examined. The BETSAH-CT achieved a maximum outlet air temperature of 110.1 °C at 10 kg/h and an average temperature of 89.7 °C at 10 kg/h. The highest useful heat gain noted as 663.8 W at 50 kg/h. The thermal efficiency increased with air flow rate, reaching a peak instantaneous efficiency of 54.2% at 50 kg/h. The considerations of pressure drop and pumping power bring to the fore the ideal system performance rate of airflow. The trends of exergy efficiency are nearly similar to the trends of solar irradiance and the highest values of the exergy efficiency decreases with the flow rate. The results indicate that the BETSAH-CT design has the benefit of improving thermal efficiency and heat gain, which can be used as a sustainable and energy-efficient solution to solar-air heating.

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