Parameter Variation of Microwave Torrefaction Time of Blotong and Bagasse Briquettes

Briquettes are one way to increase the economic value of biomass. Blotong and bagasse are two biomass wastes that can pollute the environment if stored for an extended period of time. This study aimed to determine the effect of torrefaction time on the heating value of briquettes, moisture content, and the number of organic carbons. Blotong and bagasse microwave torrefaction uses 1000 watts of power and time intervals of 20, 30, 40, 50, and 60 minutes. When the best take for torrefaction between blotong and bagasse with molasses is compared, the result is 1:1:4. Based on the analysis results, the best briquettes produced have a water content of 2.1 percent, a calorific value of 5475.8 cal/gram, and an organic carbon content of 64.75 percent at a time variable of 60 minutes. These results indicate that variations in the torrefaction process time can affect the characteristics of the resulting briquettes. Based on the results obtained, the longer the torrefaction time, the lower the water content in the briquettes. Likewise, the calorific value and carbon content are also getting higher.

The Effect of Parameter Variation on Spiral Flow Inducing Cannula Performances

Spiral flow-inducing cannula has been shown in previous research to exhibit a considerable effect on flow hemodynamic. However, there is still room for improvement. In this study, several design variations were tested to determine which variants were the best in terms of flow reduction. Computational Fluid Dynamics (CFD) software was used to simulate flow within a spiral flow-inducing cannula with several variations from chamber width and angle differences. The variants were compared against each other by using several flow parameters and a selection method was employed to determine which model was the best. It was found that a variant that has the widest chamber (14 mm) and biggest angle opening (70°) from the chamber to the cannula tube was the best in several parameters, and as such was chosen as the best variant. When compared with the standard straight cannula, the reduction in flow output was recorded to be 30% which is deemed significantly. In conclusion, spiral flow cannula recorded better hemodynamic effects with lower outflow velocity and wall shear stress value.

Model order reduction of nonlinear eddy-current field using parameterized CLN

Purpose The authors derive a nonlinear MOR based on the Cauer ladder network (CLN) representation, which serves as an application of the parameterized MOR. Two parametrized CLN representations were developed to handle the nonlinear magnetic field. Simulations using the parameterized CLN were also conducted using an iron-cored inductor model under the first-order approximation. Design/methodology/approach This work studies the effect of parameter variations on reduced systems and aims at developing a general formulation for parametrized model order reduction (MOR) methods with the dynamical transition of parameterized state. Findings Terms including time derivatives of basis vectors appear in nonlinear state equations, in addition to the linear network equations of the CLN method. The terms are newly derived by an exact formulation of the parameterized CLN and are named parameter variation terms in this study. According to the simulation results, the parameter variation terms play a significant role in the nonlinear state equations when reluctivity is used, while they can be neglected when differential reluctivity is used. Practical implications The computational time of nonlinear transient analyses can be greatly reduced by applying the parameterized CLN when the number of time steps is large. Originality/value The authors introduced a general representation for the dynamical behavior of the reduced system with time-varying parameters, which has not been theoretically discussed in previous studies. The effect of the parameter variations is numerically given as a form of parameter variation terms by the exact derivation of the nonlinear state equations. The influence of parameter variation terms was confirmed by simulation.