Papers by Keyword: Smart Materials

Abstract: Buildings have become experimental grounds for architectural technology, sustainable practices, and human-centered design principles to be tested and refined. This paradigm shift has not only transformed the physical aspects of urban environments but has also redefined the relationship between architecture, end-users, and the built environment. Advancements in technology paved the way for a revolutionary approach to architecture, that involves responsiveness and adaptability to the environment, leading to the spread of the so-called Smart Architecture, buildings able to fit in with their ever-changing surroundings. Smart buildings present, in general terms, a global enhancement of their performance features, having the potential to impact the built environment in a new interacting, and engaging way, making architecture more accessible, performant, and user-friendly. This paper summarizes the results of a study aimed at identifying and classifying a sample of applications of advanced materials and technologies in the context of building envelopes, considered representative of relevant Smart Architecture solutions. The categorization will be done according to four categories: biomimicry, smart materials, kinetic elements, and 3D printed solutions. This results in a database of Smart Architecture case studies that collects brief details of each application and working principles, together with data regarding design practice, technology readiness, and economic aspects, among others.

Abstract: This study selects a single crystalline Ni-Mn-Ga alloy by its exceptional actuator attributes, high actuation speed, precise position control, rapid response to external magnetic fields, and extended operational lifespan. Researchers venture into uncharted territory, aiming to harness the potential of Ni-Mn-Ga alloy to revolutionize micropump performance and refine fluid manipulation within miniature devices. The methodology at the heart of this endeavor involves the seamless integration of this specialized alloy with microdevice technology, giving rise to a set of unique pump components that substantially boost pump efficiency. Crucially, Ni-Mn-Ga is the chosen material for the active part of the micropump. At the same time, MEMS fabrication handles the passive elements, all facilitated by the 0.18 µm semiconductor technology and Sivalco TCAD simulation software. Computational simulations validate the alloy's suitability, impressively achieving an accumulated flow volume of 0.15 x 10e-4 µL in 10 microseconds. Beyond its scientific significance, this research bridges MEMS technology and magnetic-enabled smart materials, showcasing the remarkable capabilities of Ni-Mn-Ga alloy in significantly enhancing micropump performance. These innovative solutions promise to open doors to groundbreaking applications in microfluidic systems across many scientific and industrial domains.

Abstract: The manufacturing industry has witnessed substantial interest in the advancement of 4D printing technology in recent years. This technology has enabled the production of complex structures with enhanced functionality and adaptability. Fused Deposition Modeling (FDM) has become a preferred technique for 4D printing due to its ease of use, affordability, and versatile nature. To achieve efficient and effective 4D printing, the process parameters must be optimised to ensure the desired shape recovery behaviour of the printed parts. The main objective of this study is to optimize the process parameters for the production of 4D printed components using FDM technology and Carbon Fiber reinforced Poly Lactic Acid (CF/PLA) Shape Memory Polymer Composites (SMPCs). This study examines the shape recovery properties of the printed components by modifying the process parameters, including Infill Density (ID), Geometrical Thickness (GT), and Bending Angle (BA), through the implementation of Design of Experiments (DOE) L9 Orthogonal Array (OA). Utilizing Analysis of Variance (ANOVA) to determine the significant factors and their optimum levels, the process parameters are statistically analysed. The results indicate that ID and GT are the statistically significant parameters, and the optimum levels for parameters includes 20% ID, 1.5mm GT, and 30⁰ BA led to faster shape recovery. This study demonstrates the effectiveness of the Taguchi approach in the design and optimization of the process parameters for 4D printed parts using FDM.

Abstract: Shape memory alloys (SMAs) are a type of smart material and have excellent engineering and medical applications. TiNi binary alloys possess remarkable shape recovery, mechanical properties, corrosion resistance, and excellent biocompatibility. By ternary elements addition just like Au, Pt, Pd, Hf, and Zr, increases transformation temperatures, leading to high-temperature shape memory alloys (more than 100°C) but other elements (Fe, Cu, Co, and Mo) form low-temperature shape memory alloys, (lower than 100°C). In the present work, it is reported that the effect of ternary element addition on microstructural properties, shape memory properties, mechanical properties, corrosion resistance, and biocompatibility of ternary shape memory alloys. Ag, Au, and Cu-based TiNi ternary alloys have excellent biocompatibility. The addition of ternary elements such as Ag and Nb increases corrosion resistance, Fe rises the hysteresis loop, Hf enhances thermal stability, and Mo raises workability.

Abstract: The article is devoted to the development of the composition of a thixotropic magnetorheological fluid and a laboratory setup for determining the properties and characteristics of magnetorheological fluids. The magnetorheological fluid was developed on the basis of copolymers of methyl methacrylate and n-butyl methacrylate, a mixture of diethylbenzenes, dioctylphthalate, oleic acid, and carbonyl iron of the P-10 grade. To impart thixotropic properties to the magnetorheological fluid, a 1% solution of modified urea is added. For the study of magnetorheological materials, a laboratory setup was developed that allows one to measure the yield stress, plastic viscosity, flow curves, magnetorheological characteristics and the magnetization curve. The setup includes two hydraulically connected cylindrical vessels and one external cylindrical vessel filled with the investigated magnetorheological fluid between two poles of a powerful magnet. The shear stress is determined through the magnitude of the viscous friction force that occurs when a load immersed in the liquid is evenly lifted, and the strength and induction of the magnetic field are determined by means of two Hall sensors.

Abstract: This paper presents an investigation of the dimension variations on modular magnetorheological (MR) valve with meandering flow path structure. The size variations including the inner and outer radius of the valve at radial path. The first step is conducting FEMM (Finite Element Method Magnetics) to find out the density of magnetic flux on MR valve. The obtained magnetic field density is applied to steady state models to predict pressure drop. To determine the best configuration, pressure drop and operation range are the objective of the selection process. Based on the results, MR valve with 2.75 mm inner radius radial and 9 mm outer radius radial was chosen as the best MR valve design if compared to the other MR valve designs. The results obtained from the MR valve with 2.75 mm inner radius radial and 9 mm outer radius radial are 1.79 Mpa for the pressure drop and 6.68 for the operational range. Keywords: modular magnetorheological valve, optimization, objective function, smart materials

Abstract: The effect of fiber cross-section on effective elastic and piezoelectric coefficients of piezoelectric fiber reinforced composites (PFRC) is investigated through two micromechanical analyzes viz. modified strength of materials (MSM) approach and energy approach. Results are verified with that of strength of materials (SM) approach available in the literature. A constant electric field is considered in the direction transverse to the fiber direction and is assumed to be same both in the fiber and matrix phases. It is observed that MSM and strength of materials (SM) approach predictions for the effective piezoelectric coefficient of the PFRC assessing the actuating capability in the fiber direction are in excellent agreement and also when the fiber volume fraction exceeds a critical value, this effective piezoelectric coefficient becomes significantly larger than the corresponding coefficient of the piezoelectric material of the fiber as investigated by both SM and MSM approaches. However, results of energy approach differ from both MSM and SM results and effective piezoelectric constant never exceeds to that of fiber as obtained by energy approach. It has been found for the piezoelectric fibers, cross-section of fiber has insignificant effect on the effective properties as predicted by MSM and energy approaches. Nomenclature

Abstract: Smart materials, especially environmentally responsive materials are the basis of many applications, and have attracted much more attentions. In recent years, application research of smart materials in the oil and gas industry has begun. Through principle/performance analysis, application environment comparison, and demand analysis, the application potential and application advantages of self-healing concrete, vibration energy-generating rubber and 4D intelligent structural materials in the downhole operations were evaluated. The application status of smart materials in petroleum engineering is introduced. At the same time, combined with the actual domestic engineering requirements, the long-term effect of improving underground plugging, the shale inhibition of drilling fluid, the downhole control and the efficiency of drilling operations are all proposed. For the application prospects, it is recommended to keep track of the research progress of environmentally responsive materials and carry out pre-research work on the application of advanced smart materials in the field of downhole operations.

Abstract: Nowadays, much effort is directed towards solving the energy crisis resulting from depletion of fossil fuel. This has resulted in new approaches in energy industry like developing new sources of energy and harvesting already wasted energy. One of the commonly wasted forms of energy is the vibrational energy existing in noise produced from daily life activities. The goal of this work is to put a design for an Acoustic Energy Harvesting unit that is based on a Piezo-Electric transducer that can convert sound energy of noise into electric energy. The design process followed an experimental approach. It included open circuit as well as closed circuit experiments. The open circuit experiment aimed at finding a good initial guess for incident sound frequency for optimum energy harvesting while the closed circuit experiment aimed at finding the suitable circuit electrical impedance that would maximise energy harvesting at the frequency obtained from the initial guess. The proposed design can harvest power of 0.043 μW, with voltage of 21 mV and current of 2.05 μA, at power harvesting density of 2.8x . These results are achieved at incident sound of sound pressure level (SPL) of 118 dB and frequency of 466.2 Hz.

Abstract: Smart materials technologies are most significant in 21st-century. "Smart Materials" shall have a crucial role in construction technology. These innovative materials constitute an important part of smart building systems that shall be capable to detect its surrounding, so that the smart materials behave similar to living systems. The design of smart materials involves highly integrated components and requires interdisciplinary knowledge. Smart materials, are capable of adapting to their exterior surrounding. They alter their properties by applying exterior physical stimuli and thus adapt to their external environment in best possible manner. In the process of adapting to their external environment they involve various energy conversion processes. Thus mechanical energy is converted into electrical energy and vice versa by smart materials during their functioning. Smart materials are therefore predetermined and predesigned to perform as sensors and actuators as the need be. This paper discusses various types of smart materials available, their characteristics and applications in smart infrastructure.