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With the development of the modern technology and aerospace industry, the noise pollution is remarkably affecting people’s daily life and has been become a serious issue. Therefore, it is the most important task to develop efficient sound attenuation barriers, especially for the low-frequency audible range. However, low-frequency sound attenuation is usually difficult to achieve for the constraints of the conventional mass-density law of sound transmission. The traditional acoustic materials are reasonably effective at high frequency range. This paper aims to discuss this issue.

Membrane-type local resonant acoustic metamaterial is an ideal low-frequency sound insulation material for its structure is simple and lightweight. In this paper, the finite element method is used to study the low-frequency sound insulation performances of the coupled-membrane type acoustic metamaterial (CMAM). It consists of two identical tensioned circular membranes with fixed boundary. The upper membrane is decorated by a rigid platelet attached to the center. The sublayer membrane is attached with two weights, a central rigid platelet and a concentric ring with inner radius e. The influences of the distribution and number of the attached mass, also asymmetric structure on the acoustic attenuation characteristics of the CMAM, are discussed.

In this paper, the acoustic performance of asymmetric coupled-membrane metamaterial structure is discussed. The influences of mass number, the symmetric and asymmetry structure on the sound insulation performance are analyzed. It is shown that increasing the number of mass attached on membrane, structure exhibits low-frequency and multi-frequency acoustic insulation phenomenon. Compared with the symmetrical structure, asymmetric structure shows the characteristics of lightweight and multi-frequency sound insulation, and the sound insulation performance can be tuned by adjusting the distribution mode and location of mass blocks.

Membrane-type local resonant acoustic metamaterial is an ideal low-frequency sound insulation material for its structure is simple and lightweight. How to effectively broaden the acoustic attenuation band at low frequency is still a problem. But most of researchers focus on symmetric structures. In this study, the asymmetric coupled-membrane acoustic metamaterial structure is examined. It is demonstrated that the asymmetric structure has better sound insulation performances than symmetric structure.

This paper studies the nonlinear dynamics of membrane structure considering wrinkling effect. The coupling between wrinkles and vibration is investigated elaborately, and new insight on the dynamics of wrinkled membrane is unveiled.

Based on the stability theory of plates and shells, the wrinkling model of the membrane structure is established. Considering the effects of wrinkling and nonlinearity, the dynamic response is calculated with NewMark method.

Wrinkling will impact the dynamics of the membrane structure significantly for asymmetrical tension loading cases, dynamic response of the wrinkled membrane structure can be classified into three categories: when the vibration is small, the dynamics of the wrinkled membrane structure will behave linearly, and the wrinkles will only affect the dynamic properties as initial conditions; when the vibration is relatively large, the wrinkles will interact with the vibration during the dynamic process, and the dynamics of the structure shows very complex features; when the vibration is large enough, the dynamics will be dominated by the geometric nonlinearity of large-amplitude vibration.

In the previous works on dynamics of wrinkled membrane structure, only the vibration modes have been studied, which means all those investigations are confined with linear vibration; little research has been conducted on the nonlinear dynamics of wrinkled membrane structure. In view of this, this paper presents an investigation of dynamic properties of membrane structure considering the wrinkling and geometric nonlinear effects. This research work presents some novel discoveries on the nonlinear dynamics of wrinkled membrane.

Efficient numerical assessment of performance is particularly important in digital material design of porous materials. This study aims to present an up-scaled approach to virtually investigate permeation of fluids through a real porous filter membrane with a heterogeneous micro-structure.

The method of asymptotic homogenization is applied. The structural parameters of the micro-structure are directly obtained from structural equation modeling image analysis of a commercial filter membrane without fitting procedures. The simulation results are compared to permeation experiments of gaseous nitrogen and liquid water.

The authors found that variations in the pressure gradients across the membrane, resulting from the heterogeneity of pore structure, need to be considered. Remarkable agreement between simulations and experiments is observed.

Despite some research in the field of filtration, no studies on filter membranes have been published yet, although they represent a large segment of filtration technology.

The purpose of this paper is to provide an improved structural design for accelerometers based on cantilever beam‐mass structure and offer the descriptions of sensor fabrication, packaging and experiments.

The cantilever beam‐membrane (CB‐membrane) structure is designed as the sensing element for piezoresistive accelerometers. In the CB‐membrane structure, a cantilever beam and two identical membranes as a whole part supports the proof mass. Four piezoresistors are distributed on the surface of the cantilever beam to form a Wheatstone bridge. Finite element method is used to carry out the structural analysis and determine the sensor dimensions. The sensor chip is fabricated by bulk micro‐machining technique, packaged in dual‐in‐line (DIP) way and tested.

Compared with the conventional cantilever beam‐mass (CB‐mass) structure, the CB‐membrane structure can improve the sensor's performances, including response frequency, output linearity and cross‐axis sensitivity. The results of simulation and experiments prove that the CB‐membrane accelerometer has good performances.

The accelerometer is simply packaged and the zero offset voltage has not been compensated. Moreover, the measured response frequency is lower than the simulated value. Further work and study are needed to solve these problems.

The accelerometer with CB‐membrane structure has good performances as the static and dynamic experiments show and is suitable to detect the spindle vibration of the machine tools.

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

The present study is based on finding the structural response of a tensile membrane structure (TMS) through deformation. The intention of the present research is to develop a basic understanding of reliability analysis and deflection behavior of a pre-tensioned TMS. The mean value first-order second-moment method (MVFOSM) method is used here to evaluate stochastic moments of a performance function with random input variables. Results suggest the influence of modulus of elasticity, the thickness of the membrane, and edge span length are significant for reliability based TMS design.

A simple TMS is designed and simulated by applying external forces (along with prestress), as a manifestation of wind and snow load. A nonlinear analysis is executed to evaluate TMS deflection, followed by calculating the reliability index. Parametric study is done to consider the effect of membrane material, thickness and load location. First-order second moment (FOSM) is used to evaluative the reliability. A comparison of reliability index is done and deflection variations from μ − 3s to μ + 3s are accounted for in this approach.

The effectiveness of deflection is highlighted for the reliability assessment of TMS. Reliability and parametric study collectively examine the proposed geometry and material to facilitate infield design requirements. The estimated β value indicates that most suitable fabric material for a simple TMS should possess an elasticity modulus in the range of 1,000–1,500 MPa, the thickness may be considered to be around 1.00 mm, and additional adjustment of around 5–10 mm is suggested for edge length. The loading position in case of TMS structures can be a sensitive aspect where the rigidity of the surface is dependent on the pre-tensioning of the membrane.

The significance of the parametric study on material and loading for deflection of TMS is emphasized. Due to the lack of consolidated literature in the field combining reliability with deflection limits of a TMS, this work can be very useful for researchers.

The present work outcome may facilitate practitioners in determining effective design methodology and material selection for TMS construction.

The significance of parametric study for serviceability criteria is emphasized. Parameters like pre-stress can be included in future parametric studies to witness in depth behavior of TMS. Due to lack of consolidated literature in the field combining reliability with deflection limits of a TMS, this work can be very useful for the researchers. The present work outcome may facilitate practitioners in determining effective design methodology and material selection for TMS construction.

The purpose of this exhaustive experimental study is to investigate the fluid-structure interaction in the flexible membrane wings over a range of angles of attack for various Reynolds numbers.

In this paper, an experimental study on fluid-structure interaction of flexible membrane wings was presented at Reynolds numbers of 2.5 × 10⁴, 5 × 10⁴ and 7.5 × 10⁴. In the experimental studies, flow visualization, velocity and deformation measurements for flexible membrane wings were performed by the smoke-wire technique, multichannel constant temperature anemometer and digital image correlation system, respectively. All experimental results were combined and fluid-structure interaction was discussed.

In the flexible wings with the higher aspect ratio, higher vibration modes were noticed because the leading-edge separation was dominant at lower angles of attack. As both Reynolds number and the aspect ratio increased, the maximum membrane deformations increased and the vibrations became visible, secondary vibration modes were observed with growing the leading-edge vortices at moderate angles of attack. Moreover, in the graphs of the spectral analysis of the membrane displacement and the velocity; the dominant frequencies coincided because of the interaction of the flow over the wings and the membrane deformations.

Unlike available literature, obtained results were presented comparatively using the sketches of the smoke-wire photographs with deformation measurement or turbulence statistics from the velocity measurements. In this study, fluid-structure interaction and leading-edge vortices of membrane wings were investigated in detail with increasing both Reynolds number and the aspect ratio.

This paper seeks to modify the determinations of flow rate and fluid resistance, which can be realized and confident from the measurements of flow rates in experiments.

According to coupled physics of solid membrane and lubrication fluid, finite element method is used simultaneously to determine membrane deflection and film thickness. Several cases are simulated by traditional method, finite element method and compared with experimental method for the flow rates and fluid resistances to present the modification of determination results.

The FEM results for the fixed eight‐section are approximated to actual flow rate and are consistent with the modified determination of the flow rates, and so the modified determinations of the flow rates are verified. When a computer of P4 with 1.8 GHz CPU and 512 MB RAM is utilized, time needed for traditional method or modified formula is fewer than one second. However, more than 4 h is required for FEM by using the same computer.

This study provides the modified method for the determinations of flow rate and fluid resistance in membrane‐type restrictors by using FEM. The FEM results can increase the determination accuracy of the flow rate and restriction coefficient in the design of membrane‐type restrictors.

The purpose of this paper is to discuss the fabrication technology and test of thermo-pneumatic actuator utilizing Si₃N₄-polyimide thin film membrane. Thin film polyimide membrane capped with Si₃N₄ thin layer is used as actuator membrane which is able to deform through thermal forces inside an isolated chamber. The fabricated membrane will be suitable for thermo-pneumatic-based membrane actuation for lab-on-chip application.

The actuator device consisting of a micro-heater, a Si-based micro-chamber and a heat-sensitive square-shaped membrane is fabricated using surface and bulk-micromachining process, with an additional adhesive bonding process. The polyimide membrane is capped with a thin silicon nitride layer that is fabricated by using etch stop technique and spin coating.

The deformation property of the membrane depend on the volumetric expansion of air particles in the heat chamber as a result of temperature increase generated from the micro-heater inside the chamber. Preliminary testing showed that the fabricated micro-heater has the capability to generate heat in the chamber with a temperature increase of 18.8 °C/min. Analysis on membrane deflection against temperature increase showed that heat-sensitive thin polyimide membrane can perform the deflection up to 65 μm for a temperature increase of 57°C.

The dual layer polyimide capped with Si₃N₄ was used as the membrane material. The nitride layer allowed the polyimide membrane for working at extreme heat condition. The process technique is simple implementing standard micro-electro-mechanical systems process.

This paper aims to numerically study the effects of boundary conditions, pre-stress, material constants and thickness on the dynamic performance of a wrinkled thin membrane.

Based on the stability theory of plates and shells, the dynamic equations of a wrinkled thin membrane were developed, and they were solved with the Lanczos method

The effects of wrinkle-influencing factors on the dynamic performance of a wrinkled membrane are determined by the wrinkling stage. The effects are prominent when wrinkling deformation is evolving, but they are very small and can hardly be observed when wrinkling deformation is stable. Mode shapes of a wrinkled membrane are sensitive to boundary conditions, pre-stress and Poisson’s ratio, but its natural frequencies are sensitive to all these five factors.

The research work in this paper is expected to help understand the dynamic behavior of a wrinkled membrane and present access to ensuring its dynamic stability by controlling the wrinkle-influencing factors.

Very few documents investigated the dynamic properties of wrinkled membranes. No attention has yet been paid by the present literature to the global dynamic performance of a wrinkled membrane under the influences of the factors that play a pivotal role in the wrinkling deformation. In view of this, this paper numerically studied the global modes and corresponding frequencies of a wrinkled membrane and their variation with the wrinkle-influencing factors. The results indicate that the global dynamic properties of a wrinkled membrane are sensitive to these factors at the stage of wrinkling evolution.