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Phenomenological modeling and simulation of a textile stenter

Parra LLanos, John Wilmer; Santos, Rossane; Bastos Quadri, Marintho; Martins, Ianto Oliveira (Textile Research JournalWashintong D.C , Estados Unidos, 2020-04-28)

Mathematical modeling and simulation of cotton fabric drying in a stenter machine was performed using a finite element method. A standard κ-ɛ turbulence model was coupled with heat/mass transfer in porous media models. A ...
Production of bioethanol from rice husk pretreated with alkalis and hydrolyzed with acid cellulase at pilot scale

Cacua Silva, Alejandra; Rodriguez Ordonez, Dora Cecilia; Parra LLanos, John Wilmer (Journal of Physics: Conference Series, 2018-12-07)

Rice husk (RH) is the main biomass byproduct of the rice industry, so much that it corresponds to 20% of the total cereal production and is generally considered a waste. Due to its content of cellulose and hemicellulose, ...
Production sequencing in a flow shop system using optimization and heuristic algorithms

Caicedo-Rolón, Alvaro Jr; Parra LLanos, John Wilmer (Gestao e ProducaoBrasilia,Brasil, 2021-03-31)

The purpose of the research was to determine the sequencing of the production of n jobs in m operations in a small footwear company in an environment of flow shop machine characteristics, which optimizes the total time ...

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Phenomenological modeling and simulation of a textile stenter
...
Parra LLanos, John Wilmer | 2020-04-28

Mathematical modeling and simulation of cotton fabric drying in a stenter machine was performed using a finite element method. A standard κ-ɛ turbulence model was coupled with heat/mass transfer in porous media models. A novel approach to simulate all injectors enabled a new perspective of the process and the calculation of local convective coefficients. Three simulations were run: Simulation I reproduced real operational conditions; Simulations II and III estimated the effects of increasing drying air inlet velocity and decreasing translational velocity of the fabric, respectively. The highest drying air velocities occurred at the nozzles on the edges of the injectors, leading to high convective heat and mass transfer coefficients. Results indicated the drying process was not uniform along the fabric’s width. The models were acceptable in realistically predicting the drying of a cotton fabric in a stenter machine and could be useful in optimizing the stenter design considering the final product’s quality and energy consumption.

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Production of bioethanol from rice husk pretreated with alkalis and hydrolyzed with acid cellulase at pilot scale
...
Cacua Silva, Alejandra | 2018-12-07

Rice husk (RH) is the main biomass byproduct of the rice industry, so much that it corresponds to 20% of the total cereal production and is generally considered a waste. Due to its content of cellulose and hemicellulose, the RH has a great potential for its alternative use in the production of bioethanol, since it has a great advantage with respect to the conventional raw materials used (sugar cane, corn, beet and sweet sorghum, among others), given that this lignocellulosic material is abundant and does not compete with the food industry. The objective of this work was to obtain bioethanol from rice husk at a pilot scale, taking advantage of its cellulose and hemicellulose content. For this, a sample of 450g of RH was taken, which was pretreated with a 2.00% w/v NaOH solution and subsequently hydrolyzed with acid cellulase (CFB3S). The alcoholic fermentation of total reducing sugars (TRS) obtained in the enzymatic hydrolysis was carried out with Saccharomyces cerevisiae, finally, the fractional distillation of the must was carried out, by means of which four bioethanol samples were obtained with concentrations of 71.3% v/v, 30.0% v/v, 10.3% v/v, and 5.3% v/v of alcohol, which when mixed produced a sample of 95mL of solution with a concentration of 27% v/v alcohol (4.70g/100g of RH).

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Production sequencing in a flow shop system using optimization and heuristic algorithms
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Caicedo-Rolón, Alvaro Jr | 2021-03-31

The purpose of the research was to determine the sequencing of the production of n jobs in m operations in a small footwear company in an environment of flow shop machine characteristics, which optimizes the total time of completion of the job in the production system (Makespan). We used heuristic algorithms that were applied through Lekin and WinQSB softwares, and for the optimization algorithm we designed a mathematical model that was solved by Juliabox software. Results show that the integer linear programming and local search minimize the makespan with 3807 minutes, and different production sequences for each algorithm, which consider permutation, which improves the traditional way of programming the production in 97 minutes, however, the optimization presents better results in the performance measures of average waiting time, average time of flow, and average job in process. Application of heuristic algorithms proves to be simple and fast, but the mathematical model of optimization designed and encoded in the software is a flexible and valuable tool for decision making in production programming, which could be applied in other footwear companies, and in other productive sectors whose companies have the same characteristics of the case study, reducing costs and improving delivery times.

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Listar Química Básica Aplicada – GIQUIBA por título

Phenomenological modeling and simulation of a textile stenter

Production of bioethanol from rice husk pretreated with alkalis and hydrolyzed with acid cellulase at pilot scale

Production sequencing in a flow shop system using optimization and heuristic algorithms

Envíos recientes

Phenomenological modeling and simulation of a textile stenter

Production of bioethanol from rice husk pretreated with alkalis and hydrolyzed with acid cellulase at pilot scale

Production sequencing in a flow shop system using optimization and heuristic algorithms

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Listar Química Básica Aplicada – GIQUIBA por título

Phenomenological modeling and simulation of a textile stenter ﻿

Production of bioethanol from rice husk pretreated with alkalis and hydrolyzed with acid cellulase at pilot scale ﻿

Production sequencing in a flow shop system using optimization and heuristic algorithms ﻿

Envíos recientes

Phenomenological modeling and simulation of a textile stenter

Production of bioethanol from rice husk pretreated with alkalis and hydrolyzed with acid cellulase at pilot scale

Production sequencing in a flow shop system using optimization and heuristic algorithms

Portales Institucionales

Phenomenological modeling and simulation of a textile stenter

Production of bioethanol from rice husk pretreated with alkalis and hydrolyzed with acid cellulase at pilot scale

Production sequencing in a flow shop system using optimization and heuristic algorithms