Scientia cum Industria

Study of the influence of adding Al2O3 nanoparticles to biodiesel on the performance and emissions characteristics of a diesel engine

2024-02-20T18:45:39-03:00

The use of biodiesel in compression ignition (CI) engines has great potential to reduce emissions and the dependence on fossil fuels. However, the complete adoption of biodiesel in CI engines is limited by several drawbacks. A promising solution to these problems is the addition of nanoparticles to biodiesel or diesel-biodiesel blends. Hence, this paper studies the impact of adding aluminum oxide (Al₂O₃) nanoparticles on the performance and emission characteristics of a diesel engine running on biodiesel and a mixture of diesel and biodiesel. Al₂O₃nanoparticles were added at concentrations of 50, 100 and 150 ppm to biodiesel (B100) and a mixture of 50 % biodiesel and 50 % commercial diesel (B50). The results indicated an increase in fuel conversion efficiency and a reduction in specific fuel consumption. The highest fuel conversion efficiency was 26.5 % for B50 with 100 ppm of Al₂O₃, indicating an improvement of around 28.6 % compared to diesel fuel (B0). In general, CO emissions were reduced with the addition of nanoparticles, with a maximum reduction of 42.8 % for B100 with 50 ppm Al₂O₃ compared to B0. The highest reduction in NO_X emissions was 30.3 % for B50 with 100 ppm Al₂O₃ compared to pure diesel B0.

Study of the influence of tack resins on elastomeric formulations and applied evaluation methodologies

2024-05-21T14:14:02-03:00

In this study, we examined the impact of eight distinct types of tack resins sourced from diverse origins (phenol-formaldehyde: SP – 1068, CRJ – 418, Koresin and SRF – 1501; hydrocarbons: Unilene A – 90 and Plastack RB 809; coumarone and breu) in several elastomeric formulations. For this purpose, it was developed a simple, robust and easily reproducible tack test employing synthetic rubber to assess these formulations. The elastomeric compounds were characterized by attenuated total reflectance Fourier transform infrared spectroscopy, rheometry, Mooney viscosity, crosslinking density by swelling in solvent, hardness, abrasion wear, tensile and tear strength, followed by tack tests. Overall, the formulations exhibited similar physical-mechanical properties. Regarding the tack test results, SP-1068 (phenol-formaldehyde) and Plastack RB 809 (hydrocarbon) resins demonstrated higher values, whereas the resorcinol-type phenol-formaldehyde presented a reduction of 10.7 %. Furthermore, interference from the functional groups in the resin’s chemical structure, difficulty in interacting with the matrix, and lower crosslink density were observed. In conclusion, the developed methodology proved satisfactory in yielding reliable and reproducible tack values.

Utilização do modelo de otimização de corte unidimensional para aumento da eficiência do processo de pintura em uma indústria moveleira

2024-02-20T21:54:21-03:00

Um dos processos industriais que compõem uma indústria moveleira é o processo de pintura, geralmente composto por uma esteira na qual as peças são colocadas para que sejam pintadas. O objetivo do presente estudo é permitir o aprimoramento da etapa produtiva de pintura realizada em uma indústria moveleira da Serra Gaúcha a partir do desenvolvimento e aplicação de um modelo de otimização. Devido à forma como é realizado o processo de pintura, o emprego do modelo de otimização para solução do problema de corte unidimensional se mostra adequado. Para aplicação da solução da otimização, foi desenvolvida uma rotina em Python para geração dos padrões de corte, além da utilização do sistema CPLEX para obtenção das soluções otimizadas. O estudo conduzido foi dividido em duas etapas, na primeira etapa foram gerados os resultados da otimização para cinco cenários reais de produção e, na segunda etapa, foi realizado um comparativo com os desempenhos reais. Neste comparativo, obteve-se um ganho geral de aproximadamente 64 % na redução do desperdício observado na organização das peças na esteira de pintura. Como a realização do estudo, foi possível observar que a aplicação da otimização no processo de pintura apresenta um alto potencial de ganhos, com redução de desperdícios e consequente aumento de produtividade.

Use of the one-dimensional cutting stock optimization model to increase efficiency of painting process in a furniture industry

Abstract: One of the industrial processes that make up a furniture industry is the painting process, generally consisting of a conveyor belt on which the pieces are placed to be painted. The objective of the present study is to allow the improvement of the painting production stage carried out in a furniture industry in Serra Gaúcha through the development and application of an optimization model. Due to the way the painting process is carried out, the use of an optimization model to solve the one-dimensional cutting stock problem is appropriate. To apply the optimization solution, a Python routine was developed to generate cutting patterns, in addition to using the CPLEX system to obtain optimized solutions. The study conducted was divided into two stages, in the first stage the optimization results were generated for five real production scenarios, in the second stage, a comparison was made with the real performances. In this comparison, an overall gain of approximately 64 % was achieved in reducing waste observed when organizing parts on the painting mat. As the study was carried out, it was possible to observe that the application of optimization in the painting process presents a high potential for gains, with a reduction in waste and a consequent increase in productivity.