Browsing by Subject "smart materials"

Now showing 1 - 8 of 8

Access status: Open Access ,
A new BEM for modeling and simulation of 3T MDD laser-generated ultrasound stress waves in FGA smart materials
(Wydawnictwa AGH, 2021) Fahmy, Mohamed Abdelsabour
The goal of this study is to present a new theory known as the three-temperature memory-dependent derivative (MDD) of ultrasound stress waves in functionally graded anisotropic (FGA) smart materials. It is extremely difficult to address the difficulties related to this theory analytically due to its severe nonlinearity. As a result, we suggest a new boundary element method (BEM) to solve such equations. The suggested BEM technique incorporates the benefits of both continuous and discrete descriptions. The numerical results are visually represented to demonstrate the impacts of MDD three temperatures and anisotropy on the ultrasound stress waves in FGA smart materials. The numerical findings verify the proposed methodology's validity and accuracy. We may conclude that the offered results are useful for comprehending the FGA smart materials. As a result, our findings contribute to the advancement of the industrial applications of FGA smart materials.
Access status: Open Access ,
Analysis of the dependence between a temperature and working parameters of the MR damper
(Wydawnictwa AGH, 2007) Bajkowski, Jerzy; Bajkowski, Marcin; Grzesikiewicz, Wiesław; Sofonea, Mircea; Shillor, Meir; Zalewski, Robert
In this paper detailed description of temperature influence on MR damper working parameters has been described. Prototype of such a device and its mathematical description taking into considerations a thermal balance, have been proposed. Basing on experimental results, a connection between temperature and operating parameters of tested MR damper has been revealed.
Access status: Open Access ,
Comparison of passive and active methods for sound radiation reduction from the clamped plate
(2010) Kozupa, Michał; Wiciak, Jerzy
The paper is an analytical and experimental study of smart structure, which consist of steel plate with bonded PZTs and porous elastomer layer. Active control of sound radiation from a clamped at the edge square plate is examined. Simulations and numerical computation of the experiment are performed in ANSYS environment. Calculations of plate vibration and sound radiation under stepped harmonic force are performed. The experimental set-up is placed in coupled reverberation chambers and the test plate is placed in the hole. A variety o test cases were studied for three different plates: steel plate + PZT, steel plate + elastomer layer, steel plate + PZT + elastomer layer. The aim of the paper is to illustrate the possibilities of using piezoelectric materials as an active control and elastomer layers as passive methods in one structure to improve the transmission loss.
Access status: Restricted ,
Integration of sensing surfaces on composites
(Data obrony: 2019-10-25) Zdybał, Dominik
Wydział Inżynierii Materiałowej i Ceramiki
Access status: Open Access ,
Measurements of SMA properties using advanced optical methods
(2010) Rączka, Waldemar Stanisław; Sioma, Andrzej
Shape Memory Alloys are called smart or advanced materials because of their special features which are very useful in the latest solutions. Therefore, it is very important to gain a good knowledge of all these features for the purposes of modeling, describing, and ultimately controlling the behavior of these materials. This paper describes how to measure selected properties of SMA. It describes how to measure real temperature and diameter of thin SMA wires. At the end, we use a high speed camera to find out how an SMA wire breaks during stretching.
Access status: Open Access ,
Modeling and simulation of piezoelectric elements - comparison of available methods and tools
(Wydawnictwa AGH, 2008) Staworko, Michał; Uhl, Tadeusz
The paper presents an overview of modeling techniques of piezoelectric elements and a comparison of a software for simulation mechanical and electro-mechanical systems with a piezoelectric transducer. The described models are applied to simulate a two degrees-of-freedom mechanical system with passive damping, a two-layer and multi-layer piezoelectric bimorph. The results of simulations preformed by the use of the presented software packages are being discussed.
Access status: Open Access ,
Shape-memory materials as control elements used in dot Braille actuator
(Wydawnictwa AGH, 2014) Bryła, Jakub; Martowicz, Adam
The objective of this paper is to show a designing process for actuators that utilizes shape-memory materials. Analytical studies are carried out to design a dot actuator to be used in an electronic Braille display. Shape-memory materials are a relatively new group of smart materials that exhibit the transformation of their internal structures in solid state phases resulting from external mechanical or thermal excitation. This unique property shows up as three phenomena: one- and two-way memory effects as well as superelasticity, which all significantly influence the change of both the material properties and geometry. Hence, shape-memory materials are used as actuators effectively controlled by the above-mentioned types of excitation. The work presents the design guidelines for a proposed technical solution as well as the phenomenon utilized in the elaborated model of the actuator. The authors derived the mathematical descriptions for the proposed design configuration and an example of the calculations is shown. Moreover, the characteristics of the elaborated configuration are also discussed, taking into account the range of application areas.
Access status: Open Access ,
Wettability gradient of photoresponsive electrospun yarns for harp-based fog water harvesting
(2024) Parisi, Gregory; Szewczyk, Piotr K.; Narayan, Shankar; Stachewicz, Urszula
WIMiIP
Fog water harvesting offers a solution to water scarcity. Here, we introduce a method to enhance fog water harvesting systems utilizing electrospun yarns featuring a wettability gradient. These yarns, made from polyvinylidene fluoride (PVDF) and titanium dioxide (TiO2), gain photoinduced hydrophilicity under UV light due to TiO2 photocatalytic properties, allowing dynamic shifts from hydrophobic to hydrophilic states. Experiments show that an alternating PVDF-TiO2 harp with a wettability gradient surpasses purely hydrophobic or hydrophilic versions in fog collection. The strategic mix of hydrophobic and hydrophilic sections enhances droplet movement and water capture, achieving a 16% increase in collection rate up to 400 mg cm−2 h−1. This approach introduces a novel method for creating wettability gradients in electrospun yarns via UV irradiation and represents a significant advancement in adaptable fog water harvesting systems.