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The development of thermal energy storage systems is a possible solution in the search for reductions in the difference between the global energy supply and demand. In this context, the ability of some materials, the so-called phase change materials (PCMs), to absorb and release large amounts of energy under specific periods and operating conditions has been verified. The applications of these materials are limited due to their low thermal conductivity, and thus, it is necessary to associate them with high-conductivity materials, such as metals, to make the control of energy absorption and release times possible. Bearing this in mind, this paper presents a numerical analysis of the melting process of a PCM into a triplex tube heat exchanger (TTHX) with finned copper tubes, which allowed for the heat transfer between a heating fluid (water) and the phase change material to power a liquid-desiccant air conditioning system. Through the analysis of the temperature fields, liquid fractions, and velocities, as well as the phase transition, it was possible to describe the material charging process; then, the results were compared with experimental data, which are available in the specialized literature, and presented mean errors of less than 10%. The total required time to completely melt the PCM was about 105.5 min with the water being injected into the TTHX at a flow rate of 8.3 L/min and a temperature of 90 °C. It was observed that the latent energy that accumulated during the melting process was 1330 kJ, while the accumulated sensitive energy was 835 kJ. The average heat flux at the internal surface of the inner tube was about 3 times higher than the average heat flux at the outer surface of the TTHX intermediate tube due to the velocity gradients that developed in the internal part of the heat exchanger, and was about 10 times more intense than those observed in the external region of the equipment.

Smart materials are a class of materials characterized by having a different behavior due to external stimulation, which can be mechanic, thermal, electric, or magnetic. This chapter approaches the different types of smart materials and their classification according to the material’s nature (fluid, ceramic, polymeric and metallic). Emphasis is given to the theoretical study of the metallic materials with shape memory, presenting the fundamentals, crystallographic study and the mathematical methods of phase transformation. Due to these metallic material’s unique features, shape memory effect and super elasticity, the usage in the production of composite structures has gained space. Such materials present several advantages if compared to traditional composites being subject of research for several industrial applications

SMART materials have gained several applications in industries, especially aeronautical and biomedical. Therefore, the fabrication process of these materials must present quality in the completion and dimensioning, in addition to well established mechanical properties. In this sense, the Resin Transfer Molding (RTM) process is presented as an alternative to the manufacture of such products. This process presents advantages compared to other methods, such as, product quality and low cost. Thus, this work aims to model and simulate numerically the manufacturing process of polymer composite reinforced with NiTi shape memory alloy by RTM using the Ansys CFX commercial software. Results of pressure, velocity and volume fractions fields of the phases are presented and discussed. It was verified that the process parameters, like injection pressure and resin inlet and air outlet positions influenced the total time of the process and final product quality.

The growing global demand for energy has led researchers to seek the improvement of technology in order to maximize the generation of electricity by different ways. Among the different methods of production is the energy produced by thermal power plants, which account for more than 60% of the energy produced in the world. This energy is generated through combustion of fuels such as coal, diesel oil, natural gas and others. The main problem caused by the production of thermal energy is the emission of gaseous pollutants into the atmosphere, such as carbon dioxide (CO2), sulfur dioxide (SO2), nitrogen oxides (NOx), and also particulate matter which causes environmental problems such as acid rain, greenhouse effect, and health problems, especially respiratory diseases. Computational fluid dynamics (CFD) is presented as an important tool in solving problems involving the dispersion of chemicals into the atmosphere. In this sense, this study aims to evaluate the thermofluid dynamics of pollutants’ dispersion emitted from the chimney of a thermal power plant, based on numerical simulations using the Ansys CFX 12.0 commercial code. Fields of velocity and mass concentration of the component involved in the process are presented and analyzed.

Multiphase flow of oil, gas and water occurs in the petroleum industry from the reservoir to the processing units. The occurrence of heavy oils in the world is increasing significantly and points to the need for greater investment in the reservoirs exploitation and, consequently, to the development of new technologies for the production and transport of this oil. Therefore, it is interesting improve techniques to ensure an increase in energy efficiency in the transport of this oil. The core-flow technique is one of the most advantageous methods of lifting and transporting of oil. The core-flow technique does not alter the oil viscosity, but change the flow pattern and thus, reducing friction during heavy oil transportation. This flow pattern is characterized by a fine water pellicle that is formed close to the inner wall of the pipe, aging as lubricant of the oil flowing in the core of the pipe. In this sense, the objective of this paper is to study the isothermal flow of heavy oil in curved pipelines, employing the core-flow technique. A three-dimensional, transient and isothermal mathematical model that considers the mixture and k-e turbulence models to address the gas-water-heavy oil three-phase flow in the pipe was applied for analysis. Simulations with different flow patterns of the involved phases (oil-gas-water) have been done, in order to optimize the transport of heavy oils. Results of pressure and volumetric fraction distribution of the involved phases are presented and analyzed. It was verified that the oil core lubricated by a fine water layer flowing in the pipe considerably decreases pressure drop.

This paper aims to study the manufacturing process of polymer composite reinforced with shape memory metal alloys by RTM process using ANSYS CFX ® software. The mathematical modeling consists of mass and momentum conservation equations applied to a metal mold with dimensions 0.3 × 0.3 × 0.002 m³ containing ten NiTi alloy wires 0.0005 m diameter. Results of the flow front position of the resin (polyester resin mixed with calcium carbonate particles), pressure, streamlines and resin velocity fields during the process are presented and discussed. We conclude that the addition of calcium carbonate resulted in increased resin viscosity and greater inlet pressure obtained at the entrance of the mold which resulted in short time to full fill the mold and the highest pressures at the NiTi alloy wire surface were obtained in the central region and near the mold entrance.

In the oil industry the multiphase flow occur throughout the production chain, from reservoir rock until separation units through the production column, risers and pipelines. During the whole process the fluid flows through the horizontal pipes, curves, connections and T joints. Today, technological and economic challenges facing the oil industry is related to heavy oil transportation due to its unfavourable characteristics such as high viscosity and high density that provokes high pressure drop along the flow. The coreflow technique consists in the injection of small amounts of water into the pipe to form a ring of water between the oil and the wall of the pipe which provides the reduction of friction pressure drop along the flow. This paper aim to model and simulate the transient two-phase flow (water-heavy oil) in a horizontal pipe and T joint by numerical simulation using the software ANSYS CFX® Release 12.0. Results of pressure and volumetric fraction distribution inside the horizontal pipe and T joint are presented and analysed.

Drying can be defined as a simultaneous heat and mass transfer process between product and air drying. These phenomena have occurred due to thermal and moisture gradients and they are affected by different parameters. The inadequate management of this process can cause severe damage to the product such as cracking, loss of nutritional properties and even loss of the product quality. Thus, this paper proposes a numerical study of heat and mass transfer that occurs during the rough rice drying process, using the commercial software ANSYS CFX®. Herein the grain was considered as ellipsoid of revolution.

The occurrence of heavy oils in the world has increased substantially and points favorable to investment in exploration of mineral deposits and consequently, for the development of new technologies. Heavy oil has a high viscosity that varies from 100 to 10,000 times greater than the viscosity of water. The high pressure due to friction and viscous effects during the transport of heavy oil has been a major challenge, for itself to be economically viable for production or transportation. The core annular flow technique is a more recent technology favorable the explotation and transportation of heavy oils that provides a considerable reduction of pressure drop during the flow of these oils type. In this sense, this paper presents a 3D numerical study involving the heavy oil transportation in curved pipes, using the core-flow technique by CFD (ANSYS CFX® 12.0). Results of pressure, velocity, volume fraction and temperature distribution of the heavy oil are presented and analysed.