Cutting Line Design Method for Woven Composite Materials Fitting to Free Surface

On the fitting process simulation, the dangerous area related with buckling or tearing phenomena is identified with special colors and values, then deleting, cutting line designing, refitting and spreading processes are implemented to obtain a reasonable blank shape with dart feature. Moreover, a so called expanding surface method was presented in order to realize the fitting and spreading of free surface with hole feature. The above provided methods are realized through software codes and used in some cases effectively.

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CFD analysis and RSM optimization of obstacle layout in Tesla micromixer

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2021-0087 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Xiaowen Wang ◽

Lihong Yang ◽

Fujia Sun

Keyword(s):

Chemical Reaction ◽

Chemical Engineering ◽

Design Method ◽

Mixing Rate ◽

Special Flow ◽

Surface Method ◽

Rsm Optimization ◽

Effective Technology ◽

Optimal Design Method ◽

Lateral Offset

Abstract As a kind of fast and efficient mixing equipment, micromixer has been applied to chemical reaction detection. Its application can not only save experimental samples but also reduce the experimental time. In micromixers, Tesla structure is widely used due to its simple structure and special flow mechanism. In this paper, CFD and response surface method are used to analyze and verify the flow field of the configuration of adding diamond obstacles in the Tesla mixer. The results show that the order of layout parameter weight from large to small is obstacle size > vertical offset > horizontal offset. And the Desirability was 0.806, the optimal diamond obstacle size is 46.35 μm and the optimal lateral offset is 18.78 μm. In addition, a constant value OF 20 μm is predicted as the optimal vertical offset of the micromixer. Compared with the Tesla-type micromixer without obstacles, the diamond-shaped barrier Tesla-type micromixer designed in this paper has higher mixing rate and lower pressure drop under the same conditions, which can be applied to chemical reactors, and can also help to improve the accuracy of chemical reaction. It can be demonstrated that the presented optimal design method of obstacles layout in Tesla mixer is a simple and effective technology to improve the liquid mixing in microfluidic devices, and it has a broad application prospect in chemical engineering.

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Impact of Secondary Flow on the Accuracy of Simplified Design Methods for Steam Turbine Stages

Volume 6: Oil and Gas Applications; Concentrating Solar Power Plants; Steam Turbines; Wind Energy ◽

10.1115/gt2012-69839 ◽

2012 ◽

Cited By ~ 1

Author(s):

Jan Schumann ◽

Ulrich Harbecke ◽

Daniel Sahnen ◽

Thomas Polklas ◽

Peter Jeschke ◽

...

Keyword(s):

Secondary Flow ◽

Steam Turbine ◽

Design Process ◽

Design Method ◽

Computing Time ◽

Leading Edge ◽

Design Methods ◽

Preliminary Design ◽

Line Design ◽

Radial Equilibrium

The subject of the presented paper is the validation of a design method for HP and IP steam turbine stages. Common design processes have been operating with simplified design methods in order to quickly obtain feasible stage designs. Therefore, inaccuracies due to assumptions in the underlying methods have to be accepted. The focus of this work is to quantify the inaccuracy of a simplified design method compared to 3D Computational Fluid Dynamics (CFD) simulations. Short computing time is very convenient in preliminary design; therefore, common design methods work with a large degree of simplification. The origin of the presented analysis is a mean line design process, dealing with repeating stage conditions. Two features of the preliminary design are the stage efficiency, based on loss correlations, and the mechanical strength, obtained by using the beam theory. Due to these simplifications, only a few input parameters are necessary to define the primal stage geometry and hence, the optimal design can easily be found. In addition, by using an implemented law to take the radial equilibrium into account, the appropriate twist of the blading can be defined. However, in comparison to the real radial distribution of flow angles, this method implies inaccuracies, especially in regions of secondary flow. In these regions, twisted blades, developed by using the simplified radial equilibrium, will be exposed to a three-dimensional flow, which is not considered in the design process. The analyzed design cases show that discrepancies at the hub and shroud section do exist, but have minor effects. Even the shroud section, with its thinner leading-edge, is not vulnerable to these unanticipated flow angles.

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Pengaruh Campuran dan Rasio Bahan Pembentuk Komposit terhadap Karakteristik Komposit Bioplastik

JURNAL REKAYASA DAN MANAJEMEN AGROINDUSTRI ◽

10.24843/jrma.2021.v09.i02.p01 ◽

2021 ◽

Vol 9 (2) ◽

pp. 157

Author(s):

Syah Banu Putra Sitepu ◽

Bambang Admadi Harsojuwono ◽

Amna Hartiati

Keyword(s):

Tensile Strength ◽

Composite Material ◽

Composite Materials ◽

Design Method ◽

Block Design ◽

Elongation At Break ◽

Factor I ◽

Method Factor ◽

Randomized Block Design ◽

Multiple Comparison Test

This research aims to determine the effect of the mixture and the ratio of the composites and their interactions to the characteristics of the bioplastic composites and to determine the mix and ratio of the composites that produce the best characteristics of the bioplastic composites. The experimental design of this study used a randomized block design method. Factor I is a mixture of composite materials consisting of maizena-glucomannan, maizena-chitosan, and maizena-carrageenan. The second factor is the ratio of the composite material mixture which consists of 5 levels, namely 100: 0, 75:25, 50:50, 25:75 and 0: 100. The experiment resulted in 15 treatment combinations and were grouped into 2 groups when the process of making bioplastic composites was obtained, so that 30 experimental units were obtained. Data were analyzed for their diversity and continued with Duncan's multiple comparison test. The observed variables which tensile strength, elongation at break, modulus young, swelling, and biodegradation time. The results showed that the mixture and the ratio of the composites forming a very significant effect on tensile strength, elongation at break, elasticity, and swelling. The interaction has a very significant effect on tensile strength, elasticity and swelling and significantly affects the elongation at break of bioplastic composites. Meanwhile, the mixture and the ratio of the ingredients to form the composites had no significant effect on the biodegradation time. Maizena:glucomannan composite with ratio (25:75) produced the best characteristics of bioplastic composites with tensile strength values of 6.99 MPa, elongation at break of 16.5%, elasticity 42.39 MPa, swelling 78.78% and biodegradable time of 7 days. There are 2 variables that have met the standard, namely: elongation at break of bioplastic composites that meet the plastic Standard SNI 7188.7: 2016 and biodegradation time has met the international plastic standard ASTM 5336 and 3 variables that do not meet the standards, namely: Tensile strength (6,99 MPa) and elasticity (42,39 MPa) do not meet the Plastic Standard SNI 7188.7: 2016 and swelling (39,1%) does not meet international plastic standards (EN 317). Keywords : bioplastic composites, maizena, glucomannan, chitosan, carrageenan

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An Improved Single-Phase Free-Surface Lattice Boltzmann Model with Surface Tension and Wall Adhesion

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.300-301.1062 ◽

2013 ◽

Vol 300-301 ◽

pp. 1062-1066

Author(s):

Yang Yu ◽

Li Chen ◽

Jian Hua Lu ◽

Guo Xiang Hou

Keyword(s):

Surface Tension ◽

Free Surface ◽

Lattice Boltzmann ◽

Single Phase ◽

Lattice Boltzmann Model ◽

Surface Model ◽

Two Phase ◽

Surface Method ◽

Free Surface Model ◽

Boltzmann Model

Free-surface model with surface tension and wall adhesion(wetting) is a very efficient technique to simulate two-phase flows with high density and viscosity ratios, such as etching and casting processes. In this paper, a conservative surface tension and wall adhesion model based on lattice Boltzmann single-phase free-surface method is proposed. The effectiveness of the model is demonstrated by simulating the flows induced by wall adhesion and surface tension, and filling processes in a 2D cavity.

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Acoustic Optimization Design Method of Gear System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1016.256 ◽

2014 ◽

Vol 1016 ◽

pp. 256-260

Author(s):

Ze Yin He ◽

Teng Jiao Lin ◽

Wen Liu ◽

Bo Liu

Keyword(s):

Simulated Annealing ◽

Optimization Design ◽

Simulated Annealing Algorithm ◽

Design Method ◽

Gear System ◽

Acoustic Properties ◽

System A ◽

Surface Method ◽

Radiation Noise ◽

Annealing Algorithm

The Response Surface Method (RSM) and Simulated Annealing Algorithm (SAA) are utilized to analysis and optimize the vibro-acoustic properties of gear system. A simple case is illustrated to demonstrate the capabilities of the acoustic optimization design method. The results show that the method of acoustic optimization design based on RSM and SAA can effectively reduce radiation noise, and provide theoretical fundament and guidance for further study on acoustic optimization design of complicated gear system.

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Sensitivity Analysis for the Spring-in of Composite Shells

Advanced Composites Letters ◽

10.1177/096369351102000503 ◽

2011 ◽

Vol 20 (5) ◽

pp. 096369351102000

Author(s):

Chensong Dong

Keyword(s):

Sensitivity Analysis ◽

Thermal Expansion ◽

Composite Materials ◽

Design Of Experiments ◽

Composite Shells ◽

Dimensional Control ◽

Surface Method ◽

Wide Range ◽

The Matrix ◽

Dimensional Variation

Composite materials are a class of engineering materials widely used in a wide range of industries. Spring-in is a common dimensional variation of composite shells. It is well known that spring-in is dependent on many factors e.g. the constituent properties and coefficients of thermal expansion (CTE). A sensitivity analysis on the spring-in is presented in this paper. The sensitivities of the spring-in to the constituent properties and CTE are studied by the Design of Experiments (DOE) and the Response Surface Method (RSM). It is shown that the spring-in is predominantly sensitive to the Poisson's ratio of the matrix and the transverse CTE of the fibres. The results can be used to estimate the uncertainty of the spring-in from the uncertainties of the constituent properties and CTE, which is potentially useful for the design of composite products with improved dimensional control.

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Seismic design and analysis of reinforced concrete buckling-restrained braced frame buildings with multi-performance criteria

International Journal of Distributed Sensor Networks ◽

10.1177/1550147719881355 ◽

2019 ◽

Vol 15 (10) ◽

pp. 155014771988135

Author(s):

Yanchao Yue ◽

Tangbing Chen ◽

Yongtao Bai ◽

Xiaoming Lu ◽

Yan Wang ◽

...

Keyword(s):

Reinforced Concrete ◽

Seismic Design ◽

Design Method ◽

Performance Criteria ◽

Main Beam ◽

Frame Structures ◽

Concrete Frame ◽

Buckling Restrained Brace ◽

Buckling Restrained Braces ◽

Line Design

Buckling-restrained braces play a critical role as the first-defendant line in dissipating seismic energy and are often used in concrete frame structures to ensure that the main beam–column members are “undamaged” or significantly elastic during medium earthquakes. The design of the reinforced concrete frame structures with buckling-restrained brace is generally based on the assumption of shear deformation of the structure. The conventional seismic design considers the “second-defendant line design” based on the geometric relationship between the axial deformation and strength of buckling-restrained braces and stratified deformation. This article proposes iterative optimization of the buckling-restrained brace design method and layout scheme based on the nonlinear structural response of the calibrated numerical model, and then approximates the nonlinear structure scheme using a linear method. Time history analyses are performed to prove that the linear design method is highly conservative for estimating seismic intensity, and the proposed design method provides more efficient damage distributions in frame components. The results of the nonlinear performance evaluation and energy analysis indicate that the method proposed in this article can meet the performance design requirements achieving multi-performance criteria.

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