Modeling and optimization of maximum available work for irreversible gas power cycles with temperature dependent specific heat

AÇIKKALP E., YAMIK H.

Journal of Non-Equilibrium Thermodynamics, cilt.40, sa.1, ss.25-39, 2015 (Scopus) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 40 Sayı: 1
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1515/jnet-2014-0030
  • Dergi Adı: Journal of Non-Equilibrium Thermodynamics
  • Derginin Tarandığı İndeksler: Scopus
  • Sayfa Sayıları: ss.25-39
  • Anahtar Kelimeler: Available work, Brayton cycle, Exergy, Finite-time thermodynamics, Internal combustion engines, Irreversibility
  • Bilecik Şeyh Edebali Üniversitesi Adresli: Evet

Özet

In classical thermodynamics, the maximum power obtained from a system is defined as exergy (availability). However, the term exergy is used for reversible cycles only; in reality, reversible cycles do not exist, and all systems are irreversible. Reversible cycles do not have such restrictions as time and dimension, and are assumed to work in an equilibrium state. The objective of this study is to obtain maximum available work for SI, CI and Brayton cycles while considering the aforementioned restrictions and assumptions. We assume that the specific heat of the working fluid varies with temperature, we define optimum compression ratios and pressure ratio in order to obtain maximum available work, and we discuss the results obtained. The design parameter most appropriate for the results obtained is presented.