The present work developed an experimental and simulation study to evaluate the influence of some operational conditions and mold design on the efficiency of an injection process used to produce polystyrene parts. The software SolidWorks Plastic was used to simulate the injection process and assess the performance of the mold considering the absence and the presence of venting. Experimental results obtained by varying the injection pressure, injection temperature as well as the mold temperature were used to validate the simulation data generated considering both mold designs. The findings revealed air entrapment at the end of the mold cavity and low process efficiency when the mold was operated with no venting, regardless the processing conditions. Simulation results indicated a remarkable increase of the process efficiency when vents were included on the parting line of the mold. In addition, the range of processing conditions which led to the highest process efficiency was virtually identified and tested in the real modified mold (with venting system). The findings revealed that the injection cycle time reduced in approximately 35% and the waste generation diminished from 65% to less than 1% when venting was included in the mold design and the optimal operational conditions were used.

The solidification of a thermoplastic during the injection process directly influences the productivity and quality of the final product. This paper presents a study of the solidification performance of parts produced by a thermoplastic injection process, verifying their dimensional, visual, and production behavior according to the variation of geometry, temperature, and design of the injection mold cooling system. SolidWorks Plastics  software was used to perform the simulations. Experiments were performed with a plastic injection mold to confront and validate the simulations. Given the comparison of different cooling geometries, the simulations made it possible to obtain parts with a shorter mold cooling cycle time. Payback analysis has the primary objective of determining which cooling system is the most viable and has the highest return on invested capital. The results demonstrated a solution for engineers and designers to justify maintenance or modifications to existing injection molds through numerical simulation.

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In several areas of engineering, it is possible to put real problems in mathematical functions; when we represent a problem with variables in the form of function, we were able to extract various information from it. This paper compared two different mathematical methods, being the finite difference method and the Fourth Order Range-Kutta method, to analyze the concentration and temperature of the water flow inside a tubular reactor. These results were compared with the analytical and experimental results of the problem, demonstrating that the Fourth Order Range-Kutta method was more advantageous than the finite difference method.

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With each passing day companies are looking more and more in the initial phase of the project, to understand the phenomena arising, so that in the execution of the project there are no failures, much less when the project is in operation. For this, the numerical simulation has been shown an increasingly efficient tool to assist the engineers and designers of machines and equipment. The Kaplan turbine design requires a high level of engineering expertise combined with a high level of knowledge in fluid mechanics, as poor design of a diffuser fin can lead to disordered turbulent flow which, when mixed with a high pressure drop, can cavitate into turbine blades. The aim of this study is to evaluate different types of diffuser fin profiles in the inlet at Kaplan turbines. For this, numerical computer simulation was used with the aid of the Ansys Fluent software, in which simulations of water flow in a steady state occurred. The software works with the finite volume method for the discretization of the Navier-Stokes equations. The simulations have proved to be efficient in capturing current lines and pointing out the best flow profile in a project, avoiding more complex turbine blade problems.