Identification of factors affecting exergy destruction and engine efficiency of various classes of fuel

Energy and Exergy Characteristics of an Ethanol-Fueled Heavy-Duty Si Engine at High-Load Operation Using Lean-Burn Combustion

“…The combustion exergy destruction gained from 17.3% of total input exergy at λ = 1.0 to 20.6% at λ = 1.8. This observation confirms the conclusion in previous studies (Caton, 2017;Knizley et al, 2012;Liu et al, 2020) that the exergy destruction through combustion would not result in any additional or diminished piston work. However, the exergy destruction by the incylinder process can decrease the exhaust exergy, thereby affecting downstream devices' work potential for waste heat recovery.…”

“…The combustion exergy destruction increased from 17.3% of total exergy at λ = 1.0 to 20.6% at λ = 1.8. This finding confirms the conclusion in the literature (Caton, 2017;Knizley et al, 2012;Liu et al, 2020) that the reduction of combustion exergy destruction does not lead to any additional work. The exergy destruction by the irreversibility of the in-cylinder process only reduces the exhaust exergy and further affects the waste heat recovery devices (e.g., a turbocharger).…”

“…They highlighted fuel selection, dilution ratio, and reactant temperature as the most influential factors in terms of combustion-generated entropy. Liu et al (2020) confirmed the observation from Knizley et al (2012) in the context of engine application. In these described cases, the increased exergy destruction caused by dilution did not result in a decrease in engine efficiency, but rather in the reduction of exhaust exergy, which may affect the performance of turbochargers or other devices for waste heat recovery.…”

Energy, Exergy analysis and optimization of solar thermal power plant with adding heat and water recovery system

“…La exergía destruida también ha sido un criterio de evaluación en muchas investigaciones para realizar análisis de irreversibilidades (D. Liu et al, 2020;Zhang et al, 2020), también se ha usado la exergía destruida como un método para explorar emisiones de carbono evitables, en donde se predice el potencial de emisión de carbono evitable con la reducción de la destrucción de exergía (Wu & Wang, 2020). También se ha establecido como un criterio de selección para una estrategia como en (Gupta et al, 2020), en donde se propone una metodología que combina simulaciones fluidodinámicas con balances de energía y exergía termodinámicos para determinar la pérdida de exergía en diferentes componentes, facilitando la toma de decisiones y opciones de diseño para el refrigerado por aire basado en minimizar la irreversibilidad termodinámica.…”

Influence of cooling loss on the energy and exergy distribution of heavy-duty diesel engines based on two-stage variable supercharging, VVT, and EGR

“…They demonstrated that optimizing the fuel ratio, intake air volume, and combustion temperature can effectively improve energy conversion efficiency. Based on this work, Liu et al 24 highlighted the effect of exhaust gas quantities on the performance of energy recovery and utilization equipment, such as turbines, with larger exhaust gas quantities causing greater energy recycling. However, there is a lack of in-depth research on the coupling relation between exhaust gas exergy and parameters such as EGR, VVT, and VGT.…”