Research Information System
Thesis Type: Postgraduate
Institution Of The Thesis: Gazi University, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2024
Thesis Language: Turkish
Student: Nezahat SİVASLI
Supervisor: Nureddin Dinler
Open Archive Collection: AVESIS Open Access Collection
Abstract:
Efficient aircraft thermal management plays an essential role in preserving optimal thermal equilibrium within the aircraft. It is essential for sustaining the reliable functionality of avionic systems and other critical components, contributing to enhancing fuel efficiency, and ultimately upholding stringent safety standards. The purpose of this study is to examine the temperature effects on avionic systems under different conditions of ventilation air temperature, ventilation air mass flow rate, system locations, air outlet location, and thermal loads. To better understand the factors influencing avionic temperature, ventilation air temperature was varied between 297 K, 300 K, and 303 K, ventilation mass flow rates were varied between 0,10 kg/s, 0,15 kg/s, 0,20 kg/s, and 0,25 kg/s, and different system locations, outlet designs, and equipment thermal loads were examined under various conditions, including their original values and variations of +10 W or -10 W. Three different configurations were created for the purpose of analyzing these variables. According to the analyses, it was observed that a +10 W thermal load increases the average avionic temperatures by an average of 3,1 K, while a -10 W load results in an average decrease of 3,0 K. An increase in ventilation air mass flow rate reduces the average avionic temperatures by an average of 13,8 K, whereas an increase in ventilation air temperature leads to an average increase of 4,7 K. The changes in thermal load, ventilation air mass flow rate, and ventilation air temperature alterations demonstrate a stable pattern in the observed temperature increase or decrease among avionics. When examining two outlets at different locations with the same area, it was observed that the average avionic temperatures changed by an average of 2 K. System layout change resulted in an average temperature difference of 7,2 K. Furthermore, changes in system layout may cause up to a 20 K temperature change for some equipment while leaving others unaffected. These results clearly illustrate the impact of different geometries and environmental factors on avionic equipment. Factors such as thermal load, ventilation air mass flow rate, ventilation air temperature changes, and system layout affect avionic temperatures differently, providing valuable insights for system optimization and avionics equipment placement.
Key Words : Avionics, cooling, heat transfer, CFD