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An Overview of System of Systems and Associated Emergent Behavior
Published in Larry B. Rainey, O. Thomas Holland, Emergent Behavior in System of Systems Engineering, 2022
Entropy (the Second Law of Thermodynamics) is typically considered a measure of heat but is rather more specifically a measure of disorder in a system and observes that closed systems progress to disorder over time. Fundamentally, entropy S is defined in terms of temperature T and heat Q by: ΔS=ΔQT
Second Law of Thermodynamics
Published in Kavati Venkateswarlu, Engineering Thermodynamics, 2020
An imaginary machine that creates energy in violation of the first law of thermodynamics is called a perpetual-motion machine of the first kind (PMM1). Again, according to the Kelvin–Planck statement of the second law of thermodynamics, there can be no heat engine that has 100% efficiency. A fictitious machine that is capable of converting completely as much heat as it received from a source into another form of energy and thus becomes 100% efficient in violation of the Kelvin–Planck statement of the second law is called a perpetual-motion machine of the second kind (PMM2). A PMM2 is thus impossible. Figure 6.5 shows the PMM2.
Expressing Power Cycle Performance
Published in Neil Petchers, Combined Heating, Cooling & Power Handbook: Technologies & Applications, 2020
The first law of thermodynamics, or conservation of energy, states that energy can be neither created nor destroyed, but only converted from one form to another. The motion of the molecules causes thermal or internal energy embodied within a system. Transient forms of energy include heat and work.
Research on the usability of various oxygenated fuel additives in a spark-ignition engine considering thermodynamic and economic analyses
Published in Biofuels, 2023
Murat Kadir Yesilyurt, Battal Dogan, Abdülvahap Cakmak
Exergy specifies the quantity of the work potential of energy existing in any thermodynamic condition. According to the first law of thermodynamics, energy is conserved; to put it more clearly, the law of conservation of energy states that energy cannot be created or destroyed, but can only be transformed from one form to another. However, in contrast to energy conversion, exergy is not conserved and it is destroyed as a result of irreversibilities existing in the system. The study and use of clean alternative fuels for SI engines are of great importance in relieving the shortage of petroleum resources and environmental issues caused by fossil fuel burning. Therefore, alternative fuels for SI engines continue to be the subject of research efforts. Exergy analysis gives more valuable and detailed information than energy analysis about thermal systems, determining the exergy destruction and identifying its location, thus offering overall improvement in efficiency and playing a significant role in reducing the environmental impact caused by the investigated systems [31].
Comparison of combustion, performance, energy and exergy characteristics of a diesel engine run on plastic and tire pyrolysis oil blends with diesel
Published in International Journal of Ambient Energy, 2022
Jyothi Yarlagadda, Akash Ravuru
The credibility of any novel energy source is represented by correlating the quality and quantity of the energy in terms of energy efficiency (Al-najem and Diab 1992). To better utilise the energy, it is necessary to contemplate both the theories of energy and availability. The first and second laws of thermodynamics can be employed to achieve this. The first law of thermodynamics is about energy conservation. The second law of thermodynamics is about energy degradation, which introduces entropy. This viewpoint is termed as availability or exergy analysis. During energy conversion, its quality gets degraded and the concept of availability can be used to characterise the responsible losses (Sorathia and Yadav 2012). Energy is conserved while availability, which is the useful work that can be obtained before the system reaches equilibrium, gets destroyed in all the actual processes (Islam, Rahman, and Abedin 2011). It has been realised that this thermodynamic analysis helps in comprehending the maximum possible performance of an engine running on any fuel and the related irreversibility. Amar et al. analysed the performance of a diesel engine run on the blends of waste plastic pyrolysis oil and diesel and have observed significant improvement in the exergy of diesel when blended with plastic oil. However, it was also found that the exergy efficiency followed the reverse trend. (Das et al. 2020).
Second law analysis of the 160 Wp standalone solar photovoltaic system
Published in International Journal of Sustainable Energy, 2019
Ranjeet Kumar Jha, Avadhesh Yadav, Durgesh Sharma
According to the first law of thermodynamics, energy is neither created nor destroyed; it can be only converted from one form to another. The first law of thermodynamics deals with the quantity of energy, and it is independent of environment parameters. Total incident energy on the SPV modules is converted into electric as well as thermal energy (Lavan, Monnier, and Worek 1982). The electrical energy is high-grade energy whereas thermal energy is low-grade energy; the conversion efficiency of electrical to mechanical energy is around 99.99% whereas that of thermal energy to mechanical energy is around 40%. The amount of solar energy falling on the SPV modules is given byQin is the amount of solar energy falling on SPV modules, IR is the intensity of solar radiation falling on module area, Amod is the area of SPV module.