REVISTA DE CIENCIAS TECNOLÓGICAS (RECIT)

Design and finite element analysis of a 3D-printed packaging insert

Mon, 10 Jul 2023 00:00:00 +0000

Packaging inserts play a crucial role in protecting products during transportation. However, their design and production processes often rely on conventional methods limiting equipment capabilities. Moreover, the empirical nature of their design can result in a lack of reliability in the final product. To address these challenges, this study aimed to validate the design of a packaging insert using the finite element method and subsequently create it using 3D printing. The chosen material is a thermoplastic polyurethane (TPU) filament commonly used in fused deposition filament printers for 3D printing. This process demonstrates the feasibility of using 3D printing to create cushioning inserts for packaging and employing finite element analysis to simulate the insert behavior. The main findings of this research highlight the potential benefits of numerical simulation, revealing the areas where the insert is primarily impacted by weight. Furthermore, the forces load and displacement simulation results confirm that the TPU elastic limit (3.9x10⁶ MPa) is sufficient to handle the weight this insert intends to hold. These tools determine the viability of the proposed design for its intended application. Therefore, this study verifies that 3D printing is a reliable option for producing packaging inserts, offering significant advantages over traditional methods. These advantages include increased design flexibility and the ability to create custom inserts on demand.

Exploring the internet of things based on ESP8622: tools and case study

Wed, 20 Sep 2023 00:00:00 +0000

This project focuses on exploring internet of things based on ESP8266 by the development of an application for mobile devices with the control and monitoring operation of an automatic pet feeder. The document presents a design of a physical structure that carries all the electrical components and manages to make a connection through a server, using the MQTT protocol for messaging in time with the application from anywhere in the world using a Wi-Fi network. A series of tests of the response times of the feeder after entering the application, pressing the button, and using the same network to which the feeder is connected. The maximum response times in the servo motor were 5 seconds while the response times for the sensors were 1 second.

Effects of wind speed and temperature on economics and environmental impact assessment of different solar PV systems in Malaysia

Tijani Alhassan Salami, Ariffin Salbiah — Mon, 31 Jul 2023 00:00:00 +0000

This study aims to analyse the effect of temperature and wind speed on the performance of different types of photovoltaic (PV) systems at a different state in Malaysia and how it affects the economics and environmental impact assessment in the present year of 2018 as well as future years in 2030 and 2040. Three types of grid-connected solar PV modules namely Mono-Crystalline, Poly-crystalline, and Thin Film were selected to be implemented in different cities of Shah Alam, Chuping, Alor Setar, Ipoh and Kota Kinabalu. A mathematical model was adopted to estimate the performance characteristics of the solar PV modules. Based on the data in the present year, the highest power output produced by the Mc-Si module for Alor Setar city is given by 33.40 MWh/year while the lowest amount of power output provided by this PV panel is about 28.18 MWh/year in Shah Alam. Furthermore, an area of 144 m² for the Mono-Crystalline PV module can satisfy the total energy requirement by the resident as it was the most profitable to be implemented compared to Poly-crystalline and Thin Film. The findings of this study can serve as important information on the economic viability of installing PV systems in the selected cities in Malaysia.

Simulation of a solar heating system using Python

Tue, 19 Sep 2023 00:00:00 +0000

Currently, dependence on fossil resources continues to dominate, even with the economic-environmental impacts that they generate; Therefore, it is necessary to encourage the production and use of renewable, affordable and sustainable sources. In this sense, this work focuses on developing solar thermal simulation software for the evaluation of low-cost and low environmental impact materials that can be used in solar heaters or thermal accumulators. Optimizing the use of stone, organic materials and those available locally with optothermal properties of high absorption and great thermal residence, to use them as containers for solar thermal energy. In this way, a desktop application has been developed in the Python programming language to simulate the absorbance and thermal accumulation of materials with the aforementioned characteristics using properties such as ambient temperature of the test site, solar absorbance, thermal conductivity and mass of the material. This software aims to make experimental processes more efficient, reducing economic, technological and material resources, by having a model of the thermal physics of solar thermal accumulation in natural materials, predicting their energy behavior without the need to build full-scale prototypes. Finally, it has been proven that the developed simulator provides a much more dynamic and easy-to-interpret analysis with easily obtained statistical data. That is, it allows not only the curve to be observed but also provides the dispersion of a continuous system of values, which can help to infer research data with greater simplicity and effectiveness on the optical and thermal properties of the materials studied. However, the development of the computer program can be improved, so it maintains a free access and open-source scheme.

Cellulose hydrogel substrate modified with macroporosity by computed microtomography and 3D printing for soil-less cultivation

Ángel Iván Belmonte Torres, Juan Israel Aguilar Duque, Guillermo Amaya Parra — Sun, 17 Sep 2023 00:00:00 +0000

Soilless cultivation is an agricultural technique that allows higher crop yields, showing several advantages over traditional agriculture, this technique requires improvements in the substrates used to obtain higher production and quality. Cellulose-derived hydrogels promise to be a good alternative as substrate due to their hydrophilic properties; however, they lack good aeration. It is proposed to use cellulose as raw material for the synthesis of cellulose hydrogels assisted by computerized microtomography to generate a model with a porosity of 15-30% and reproduce it by 3D printing by digital light processing (DLP). The aim is to obtain a cellulose hydrogel substrate with better properties than commercial substrates, and to implement 3D printing in agriculture.

Obstacles to the adoption of electronic commerce in SMEs in Ciudad Juárez

Javier Martínez Romero, Miguel Antonio Delgado Gil De Arana — Mon, 11 Sep 2023 00:00:00 +0000

ICTs offer various capabilities such as electronic commerce, which allows a company to position itself internationally without the need for a physical establishment, in other words, borders are crossed through electronic means without the need to do so physically [1]. Research on the use and adoption of ICTs in Mexican SMEs show that its use is incipient [2]. The SME sector plays a crucial role in economic development, poverty reduction and job creation in developing economies [3], on the other hand, large companies are the ones that adopt these technologies the most, which generates an alert by increasing the competitiveness gap compared to SMEs, which is why it is vitally important that this sector adopt ICT [4]. In this sense, the objective of this research is to analyze the obstacles to the adoption of electronic commerce by SMEs in Ciudad Juárez. With information from a sample of 72 companies to which a questionnaire containing questions on eleven obstacles to ICT adoption is applied, the frequency of these obstacles is shown, as well as a factor analysis that shows the relationship between said obstacles. The results show that electronic commerce continues to be an ICT little adopted, although there is evidence of greater use than in the past. Variables associated with management support, capital, and infrastructure are those that are perceived as the greatest obstacles to the adoption of electronic commerce, which reinforces findings from other studies.

Numerical study of a solar collector using water and titanium dioxide water-based nanofluid as working fluids by means of computational fluid dynamics

Wed, 20 Sep 2023 00:00:00 +0000

A thermo-hydraulic performance and entropy generation comparison of an evacuated tube solar collector using water and titanium dioxide (TiO₂) water-based nanofluid as working fluids is carried out by means of Computational Fluid Dynamics. It is considered a complete 3D geometry under meteorological conditions of the city of Mexicali, Mexico under an operation time of 9 hours. It was found that, throughout the operation time, the evacuated tube solar collector had a better performance in terms of outlet temperature and velocity inside the solar collector using the nanofluid than using only water as a working fluid. The phenomena of viscous effects, heat transfer, and heat loss in a global and local form are considered in the formulation of the entropy generation. The local entropy generation formulation also allows us to illustrate the exact location of the irreversibilities. It was found that, using TiO₂water-based nanofluid as a working fluid leads to a reduction of the entropy generation in all the evacuated tube solar collectors. Finally, this type of analysis by obtaining the global and local entropy generation can be helpful to improve their performance through entropy minimization.