Süleyman KAĞAN AYAZ, Önder ALTUNTAŞ, EMİN AÇIKKALP

DÜZ UÇUŞ VE TIRMANMADA FARKLI MOTOR TİPLERİ İÇİN TAŞIMA EKSERJİSİ

Ekserji analizi, günümüzde hava trafiğinin artmasıyla birlikte hava araçlarından kaynaklanan küresel ısınma etkilerinin azaltılması ve enerjinin etkin kullanıma yönelik yapılan çalışmalarda büyük önem arz etmektedir. Bu çalışmada, teorik bir hava aracı için beş farklı motor tipinde 8,000ft (2,440m)'te düz uçuş ve deniz seviyesinde tırmanma durumları için taşıma ekserjisi tabloları oluşturulmuştur. Bu çalışma sonucunda, yakıt debisi ve gücü fazla olan motorların diğer bileşenlerinde de taşıma ekserjisi anlamında daha fazla ekserji yıkımı meydana geldiği görülmüştür. Ekserji yıkımları bileşenler arasında hem düz uçuşta hem de tırmanma durumunda en fazla motorda meydana gelmiştir. Bu bağlamda kanat ve pervane sırasıyla ikinci ve üçüncü bileşenlerdir. Daha fazla kanat açıklık oranı (aspect ratio) değerine sahip bir hava aracının tüm bileşenleri için daha az taşıma ekserjisi gerektiği görülmüştür. Düz uçuşta motor bileşeninde en fazla ekserji yıkımı yaklaşık olarak 32 kW ile gücü ikinci en yüksek olan motorda meydana gelmiştir. Tırmanma aşamasında ise en yüksek güce sahip motorda yaklaşık olarak 473 kW ekserji yıkımı meydana gelmiştir ve bu değer beş motor arasında en yüksek olanıdır

THE EXERGY OF LIFT DURING CLIMB AND CRUISE FOR DIFFERENT ENGINE TYPES

Nowadays with the increasing air traffic, exergy analysis is of great importance in studies aimed efficient use of energy and decreasing environmental impacts caused by aircrafts. In this study, tables for exergy of lift for a hypothetical aircraft have been created with five different engine types. Tables created are for cruise at 8,000ft (2,440m) and climbing at sea level. As a result of this study, it is seen that the engines with higher power and fuel mass flow rate have bigger exergy destruction rates within their components in the meaning of the exergy of lift. The exergy destructions have occurred most greatly at the engines both at the climbing and the cruise. Wing and propeller are the second and third components in this regard, respectively. It is seen that for the components of an aircraft which has a lower aspect ratio there is lesser need for the exergy of lift. During the cruise, the biggest exergy destruction rate in the engine component is occurred approximately as 32 kW at the engine which has the second highest power. As to climb, 473 kW exergy destruction rate which is the biggest value within all engines is occurred at the engine having the biggest power

PDF

___

[1]Karakoc, H., Turgut, E., Hepbasli, A.(2006), "Exergetic analysis of an aircraft turbofan engine" Proceedings, Summer Course on Exergy and its Applications, Anadolu University, Eskisehir, Turkey, 14-16.
[2]Paulus, D.M. Jr., Gaggioli, R. A., (2003) " The Exergy of Lift and Aircraft Exergy Flow Diagrams" International Journal of Thermodynamics, 6, 149-156.
[3]Bejan, A., (2002), "Fundamentals of Exergy Analysis, Entropy Generation Minimization, and the Generation of Flow Architecture" International Journal of Energy Research, 26, 545-565.
[4]Roth, B., (2001), "Aerodynamic Drag Loss Chargeability and its Implications in the Vehicle Design Process" 1st AIAA Aircraft, Technology Integration and Operations Forum, 5236.
[5]Bejan, A., Siems, D.L., (2001), "The Need for Exergy Analysis and Thermodynamic Optimization in Aircraft Development" Exergy, an International Journal, 1, 14-24.
[6]Bejan, A., (1996) "" Entropy Generation and Exergy Destruction" Entropy Generation Minimazation: The Method of Thermodynamic Optimization of Finite-Size Systems and Finite Time Processes", CRCPress, 21-42.
[7]Moorhouse, D., (2003) "Introduction: Exergy, " Journal of Aircraft, Vol. 40, No. 1, 10.
[8]Roth, B., (2003) "The Role of Thermodynamic Work Potential in Aerospace Vehicles" In:Proceedings of the 16th International Symposium on Air Breathing Engines (ISABE), Cleveland.
[9]De Oliveira, S., Jr.,(2013) "Exergy: Production, Cost and Renewability, 1st ed. ", Springer-Verlag, 249.
[10]Markell, K.C., (2005), "Exergy Methods for the Generic Analysis and Optimization of Hypersonic Vehicle Concepts" Master Dissertation, Faculty of Virginia Polytechnic Institute and State University, Blacksburg.
[11]Riggins, D. W., Moorhouse, D. J., Camberos, J. A., (2010) " Characterization of Aerospace Vehicle Performance and Mission Analysis Using Thermodynamic Availability" Journal of Aircraft, 47, No. 3, 904-916.
12]Moran, M. J., Sciubba, E., (1994), "Exergy Analysis: Principles and Practice"Journal of Engineering for Gas Turbines and Power, 116, No. 2, 285-290.
[13]Vargas, J.V.C., Bejan, A., (2001), "Integrative Thermodynamic Optimization of the Environmental Control System of an Aircraft" International Journal of Heat and Mass Transfer, 44, 3907-3917.
[14]Ordonez, J.C., Bejan, A., (2003), "Minimum Power Requirement for Environmental Control of Aircraft" Energy, 28, 1183-1202
[15]Dunbar, W.R., Lior N., (1991),"Understanding Combustion Irreversibility "ASME AES;25, 81-90.
[16]Avco Lycoming, (1973), "0-320, I0320, AIO 320 and LIO 320 Series Aircraft Engines Operator's Manual"
[17]Textron Lycoming, (2000), "O-360, HO-360,IO-360, HIO-360 & TIO-360 Series Aircraft Engines Operator's Manual"
[18]Avco Lycoming, (1982), "O-540, IO-540& HIO-540 Series Aircraft Engines Operator's Manual"