A5101508286- Acoustic Wave Phenomena Research
- Noise Effects and Management
- Vehicle Noise and Vibration Control
- Cellular and Composite Structures
- Wind and Air Flow Studies
- Engineering Applied Research
- Advanced Surface Polishing Techniques
- Advanced ceramic materials synthesis
- Mechanical Behavior of Composites
- Electric and Hybrid Vehicle Technologies
- Hearing Loss and Rehabilitation
- Metamaterials and Metasurfaces Applications
- Aerodynamics and Acoustics in Jet Flows
- Antenna Design and Analysis
- Radiative Heat Transfer Studies
- Breast Cancer Treatment Studies
- Engineering and Material Science Research
- Microbial Metabolic Engineering and Bioproduction
- Additive Manufacturing Materials and Processes
- Thin-Film Transistor Technologies
- Fire dynamics and safety research
- Industrial Technology and Control Systems
- Composite Structure Analysis and Optimization
- Vibration and Dynamic Analysis
- Fire effects on concrete materials
Nanjing Institute of Industry Technology
2020-2025
Nanjing University of Aeronautics and Astronautics
2022-2025
PLA Army Engineering University
2017-2019
Emory University
2017
This paper presents a multi-Helmholtz unit series–parallel acoustic metamaterial with segmented noise control effect designed by taking advantage of the adjustable frequency band an metamaterial, aiming to change main spectrum characteristics under different driving conditions military equipment such as tanks. Based on transfer matrix method, theoretical model that can predict hybrid structure multiple Helmholtz resonator (HR) units is established, and its feasibility verified through finite...
The Helmholtz resonance acoustic metamaterial is an effective sound absorber in the field of noise reduction, especially low-frequency domain. To overcome conflict between number resonators and volume rear cavity for each chamber with a given front area single-layer metamaterial, novel interlayer parallel connection multiple (IPC–MHR) proposed this study. developed IPC–MHR consists several layers, among different layers are connected parallel. absorption property studied by finite element...
Novel acoustic absorbers were fabricated by the compression and microperforation of porous metal, which aimed to develop practical for noise reduction. Sound absorbing coefficients five investigated measured AWA6128A detector according standing wave method, their trends consistent with normal sound absorption principle metal absorber that microperforated panel absorber. The results proved same length cavity, performance could be obviously improved microperforation. When cavity was 20 mm,...
For the common difficulties of noise control in a low frequency region, an adjustable parallel Helmholtz acoustic metamaterial (APH-AM) was developed to gain broad sound absorption band by introducing multiple resonant chambers enlarge bandwidth and tuning length rear cavity for each chamber. Based on coupling analysis double resonators, generation mechanism adjusting structural parameters analyzed, which provided foundation development APH-AM with tunable chambers. Different from other...
Rubber is widely applied in the field of electrical engineering due to its high elasticity. However, poor thermal conductivity can cause localized overheating and eventual failure. This issue be addressed through adding fillers with conductivity. In this study, natural rubber selected as matrix, while braided carbon fiber (B-CF), known for excellent conductivity, serves reinforcing phase. research defines cubic Bessel curves, establishes a curvilinear coordinate system, examines orthogonal...
The control of noise pollution in the low-frequency domain with various spectrum ranges requires development a novel tunable sound absorbing material, and multilayer stackable grouped acoustic metamaterial (MSG-AM) is proposed this research to obtain optimal reduction effect while minimizing occupied space. MSG-AM includes four layers eight Helmholtz resonators each layer divided into three groups, total 32 different are connected parallel. absorption property optimized by joint simulation...
An acoustic metamaterial absorber of parallel–connection square Helmholtz resonators is proposed in this study, and its sound absorption coefficients are optimized to reduce the noise for given conditions factory. A two–dimensional equivalent simulation model built obtain initial value parameters a three–dimensional finite element constructed simulate performance cell, which aims improve research efficiency. The optimal cells obtained through particle swarm optimization algorithm,...
Acoustic metamaterials based on Helmholtz resonance have perfect sound absorption characteristics with the subwavelength size, but bandwidth is narrow, which limits practical applications for noise control broadband. On basis of Fabry-Perot principle, a novel absorber acoustic metamaterial by parallel connection multiple spiral chambers (abbreviated as MSC-AM) proposed and investigated in this research. Through theoretical modeling, finite element simulation, sample preparation experimental...
To achieve the broadband sound absorption at low frequencies within a limited space, an optimal design of joint simulation method incorporating finite element and cuckoo search algorithm was proposed. An acoustic metamaterial multiple parallel hexagonal Helmholtz resonators with sub-wavelength dimensions designed optimized in this research. First, initial geometric parameters investigated metamaterials were confirmed according to actual noise reduction requirements reduce optimization burden...
The composite rubber reinforced with hollow glass microsphere (HGM) was a promising material for noise reduction, and its sound insulation mechanism studied based on an acoustic finite element simulation to gain the appropriate parameter certain constraint conditions. built model included air domain, polymer domain inorganic particles domain. of investigated through distributions pressure level. influences parameters transmission loss (STL) were researched one by one, such as densities HGM,...
A Helmholtz resonator (HR) with an embedded aperture is effective acoustic metamaterial for noise reduction in the low-frequency range. Its sound absorption property significantly affected by shape. Sound properties of HRs various tangent sectional shapes were studied a two-dimensional finite element simulation. The sequence resonance frequency from low to high was olive, common trapeziform, reverse dumbbell and rectangle. Meanwhile, those cross-sectional investigated three-dimensional...
The combination structure of a porous metal and microperforated panel was optimized to develop low frequency sound absorber. Theoretical models were constructed by the transfer matrix method based on Johnson—Champoux—Allard model Maa’s theory. Parameter optimizations absorbers conducted Cuckoo search algorithm. absorption coefficients structures verified finite element simulation validated standing wave tube measurement. experimental data consistent with theoretical data, which proved...
There is an increasing emphasis on the transformation of lignocellulosic biomass into versatile products. The feasibility preparing xylooligosaccharides (XOS) by hydrolysis sorghum stalk (SS) using organic and inorganic acids was studied. influences different (gluconic acid, acetic sulfuric oxalic acid), process time temperature SS were explored. findings indicated XOS yield can be maintained at a high level under conditions with acid pretreatments. Optimum (39.4%) obtained (pH 2.2) 170 °C...
The comprehensive performance of rubber products could be significantly improved by the addition functional fillers. To improve research efficiency and decrease experimental cost, mechanical thermal properties carbon-fiber-reinforced were investigated using finite element simulations theoretical modeling. simplified micromechanical model was constructed through repeatable unit cell with periodic boundary conditions, corresponding models built based on rule mixture (ROM), which can treated as...
Increasing absorption efficiency and decreasing total thickness of the acoustic absorber is favorable to promote its practical application. Four compressed porous metals with compression ratios 0%, 30%, 60%, 90% were prepared assemble four-layer gradient metals, which aimed develop high-efficiency thin thickness. Through deriving structural parameters thickness, porosity, static flow resistivity for theoretical models sound coefficients constructed through transfer matrix method according...
The limited occupied space and various noise spectrum requires an adjustable sound absorber with a smart structure tunable absorption performance. hexagonal acoustic metamaterial cell of the multiple parallel-connection resonators perforating rate was proposed in this research, which consisted six triangular cavities trapezium cavities, perforation each cavity by moving sliding block along slideway. optimal geometric parameters were obtained joint optimization finite element simulation...
The improvement of sound absorption performance porous metal is a focus research in the field noise reduction. Influences compression ratios on nickel-iron (Ni-Fe) alloy were investigated. samples compressed with from 10% to 80% at an interval 10%. Based standing wave method, coefficients different thicknesses obtained. It could be found that same ratio, was improved increase thickness. modified Johnson-Allard model correction factor, coefficient Ni-Fe thickness 20 mm for derived, whose aim...
Standardized multilayer microperforated panel fabricated by laser beam machining of the spring steel was proposed for noise reduction in this study. Geometric parameters standardized panel, which include diameter hole, thickness distance between neighbor holes, and length cavity, were optimized better sound absorption performance. Sound coefficient theoretically modeled based on Maa's theory. The optimization geometric obtained Cuckoo search algorithm, finite dimension 30 mm treated as...