This work established the fracture probability equation for JIS SM490A steel using the computational model supported by the local approach and the standard Crack Tip Opening Displacement (CTOD) fracture toughness experiments. As the experiments were conducted at a low temperature providing conditions for the brittle fracture, the specimen suffers a small plastic deformation until its failure. The computational model tries to represent the experiment results, estimating the scale and shape parameters of the Weibull distribution for the cumulative fracture probability equation. A procedure based on the local approach was executed to find the optimum values for the fracture probability equation. In addition, a plot was provided to show the distribution of likelihood values according to assumed values for the shape and scale parameters. In the end, a comparison between the experimental and predicted statistical distribution of critical CTOD was done successfully, indicating that material toughness can be predicted by the present model.
This study uses thermoeconomic analyses to compare proposed cogeneration units that use alternative internal combustion engines operating with three possible fuels: natural gas, biogas, or syngas. The technical basis of the study is thermodynamics, which enables the identification of losses and the determination of system efficiency through energy and exergy analyses conducted with the Engineering Equation Solver software. The thermodynamic tools reveal the technical potential of each energy cogeneration unit to assist the economic-technical viability analysis. The study indicates how an energy cogeneration installation with high cooling demand in commercial and industrial enterprises reduces energy costs. In the calculation of the levelized costs of electricity of the cogeneration units, the imputed electricity is the sum of the electricity saved with an absorption chiller with the electrical power produced by motor-generators. This procedure shows that the reuse of heat reduces the cost of electricity, making the hypothetical installations more economically attractive. The levelized costs obtained for syngas and biogas cogeneration units are higher than the levelized cost for the natural gas unit. However, the biogas project stands out since its levelized cost for the cogeneration unit is only six percent higher than the cost obtained for the natural gas cogeneration unit.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.