当期目录

2017年 第38卷 第6期    刊出日期：2017-06-01

上一期    下一期

论文

Scaling laws of compressible turbulence

Bohua SUN

2017, 38(6):  765-778.  doi:10.1007/s10483-017-2204-8

摘要 ( 699 )   HTML   PDF (208KB) ( 266 )  

参考文献 | 相关文章 | 多维度评价

Spatial scaling laws of velocity kinetic energy spectra for the compressible turbulence flow and the density-weighted counterparts are formulated in terms of the wavenumber, dissipation rate, and Mach number by using a dimensional analysis. We apply the Barenblatt's incomplete similarity theory to both kinetic and density-weighted energy spectra. It shows that, within the initial subrange, both energy spectra approach the -5/3 and -2 power laws of the wavenumber when the Mach number tends to unity and infinity, respectively.



Lower bound for transient growth of inclined buoyancy layer

Xiangming XIONG, Jianjun TAO

2017, 38(6):  779-796.  doi:10.1007/s10483-017-2202-8

摘要 ( 700 )   HTML   PDF (1385KB) ( 127 )  

参考文献 | 相关文章 | 多维度评价

The relationship between stabilities of the buoyancy boundary layers along an inclined plate and a vertical plate immersed in a stratified medium is studied theoretically and numerically. The eigenvalue problem of energy stability is solved with the method of descending exponentials. The disturbance energy is found to be able to grow to 11.62 times as large as the initial disturbance energy for Pr = 0.72 when the Grashof number is between the critical Grashof numbers of the energy stability and the linear stability. We prove that, with a weighted energy method, the basic flow of the vertical buoyancy boundary layer is stable to finite-amplitude streamwise-independent disturbances.

Global sensitivity analysis based on high-dimensional sparse surrogate construction

Jun HU, Shudao ZHANG

2017, 38(6):  797-814.  doi:10.1007/s10483-017-2208-8

摘要 ( 639 )   HTML   PDF (759KB) ( 245 )  

参考文献 | 相关文章 | 多维度评价

Surrogate models are usually used to perform global sensitivity analysis (GSA) by avoiding a large ensemble of deterministic simulations of the Monte Carlo method to provide a reliable estimate of GSA indices. However, most surrogate models such as polynomial chaos (PC) expansions suffer from the curse of dimensionality due to the high-dimensional input space. Thus, sparse surrogate models have been proposed to alleviate the curse of dimensionality. In this paper, three techniques of sparse reconstruction are used to construct sparse PC expansions that are easily applicable to computing variance-based sensitivity indices (Sobol indices). These are orthogonal matching pursuit (OMP), spectral projected gradient for L₁ minimization (SPGL1), and Bayesian compressive sensing with Laplace priors. By computing Sobol indices for several benchmark response models including the Sobol function, the Morris function, and the Sod shock tube problem, effective implementations of high-dimensional sparse surrogate construction are exhibited for GSA.

Jeffery-Hamel flow of non-Newtonian fluid with nonlinear viscosity and wall friction

J. NAGLER

2017, 38(6):  815-830.  doi:10.1007/s10483-017-2206-8

摘要 ( 775 )   HTML   PDF (522KB) ( 256 )  

参考文献 | 相关文章 | 多维度评价

A Jeffery-Hamel (J-H) flow model of the non-Newtonian fluid type inside a convergent wedge (inclined walls) with a wall friction is derived by a nonlinear or-dinary differential equation with appropriate boundary conditions based on similarity relationships. Unlike the usual power law model, this paper develops nonlinear viscosity based only on a tangential coordinate function due to the radial geometry shape. Two kinds of solutions are developed, i.e., analytical and semi-analytical (numerical) solutions with suitable assumptions. As a result of the parametric examination, it has been found that the Newtonian normalized velocity gradually decreases with the tangential direction progress. Also, an increase in the friction coefficient leads to a decrease in the normalized Newtonian velocity profile values. However, an increase in the Reynolds number causes an increase in the normalized velocity function values. Additionally, for the small values of wedge semi-angle, the present solutions are in good agreement with the previous results in the literature.

General semi-analytical solutions to one-dimensional consolidation for unsaturated soils

Lei WANG, De'an SUN, Aifang QIN

2017, 38(6):  831-850.  doi:10.1007/s10483-017-2209-8

摘要 ( 600 )   HTML   PDF (2530KB) ( 193 )  

参考文献 | 相关文章 | 多维度评价

This paper presents general semi-analytical solutions to Fredlund and Hasan's one-dimensional (1D) consolidation equations for unsaturated soils subject to different initial conditions, homogeneous boundaries and time-dependent loadings. Two variables are introduced to transform the two-coupled governing equations of pore-water and pore-air pressures into an equivalent set of partial differential equations (PDEs), which are solved with the Laplace transform method. The pore-water and pore-air pressures and settlement are obtained in the Laplace transform domain. The Crump's method is used to perform inverse Laplace transform to obtain the solutions in the time domain. The present solutions are more general in practical applications and show good agreement with the previous solutions in the literature.

Rayleigh-type wave propagation through liquid layer over corrugated substrate

A. K. SINGH, A. DAS, A. RAY

2017, 38(6):  851-866.  doi:10.1007/s10483-017-2205-8

摘要 ( 614 )   HTML   PDF (582KB) ( 174 )  

参考文献 | 相关文章 | 多维度评价

The propagation of the Rayleigh-type wave in a fluid layer overlying a corrugated substrate is studied. The corrugated substrate is considered as a fluid saturated poroelastic substrate and a quadratically heterogeneous isotropic elastic substrate in Case Ⅰ and Case Ⅱ, respectively. Closed form expressions of dispersion relation for Case Ⅰ and Case Ⅱ are obtained. The influence of corrugation, porosity, and heterogeneity on the phase velocity of Rayleigh-type wave, for both cases, is highlighted and demonstrated through numerical computation and graphical discussion. Neglecting corrugation at the common interface, expressions of phase velocity of the Rayleigh-type wave for both cases are derived in a closed form as a special case of the problem. Comparison between the presence and the absence of both heterogeneity and poroelasticity in the substrate of the composite structure is a key in the present study.

Mechanical model of organ of Corti

Yiqiang CHEN, Wenjuan YAO, Shaofeng LIU

2017, 38(6):  867-876.  doi:10.1007/s10483-017-2203-8

摘要 ( 538 )   HTML   PDF (377KB) ( 261 )  

参考文献 | 相关文章 | 多维度评价

According to the vibration characteristics of the organ of Corti (OC), seven hypotheses are made to simplify the structure of the model, and a mechanical OC model is established. Using the variational principle, a displacement analytical expression is solved under a certain pressure. The results are in good agreement with experimental data, showing the validity of the formula. Combined with the damage caused by noise in clinic, it is found that the hardening of outer hair cells and outer stereocilia can lead to loss of hearing and generation of threshold shift. In addition, the results show that high frequency resonance occurs at the bottom of the basilar membrane (BM), and low frequency resonance occurs at the top of the BM. This confirms the frequency selective characteristics of the BM. Further, using this formula can avoid interference of the envi-ronment and the technical level of the test personnel, and can evaluate performance of the OC objectively.

Nonlinear stability of sensor elastic element—corrugated shallow spherical shell in coupled multi-field

Yongan ZHU, Fan WANG, Renhuai LIU

2017, 38(6):  877-888.  doi:10.1007/s10483-017-2201-7

摘要 ( 591 )   HTML   PDF (238KB) ( 141 )  

参考文献 | 相关文章 | 多维度评价

Nonlinear stability of sensor elastic element—corrugated shallow spherical shell in coupled multi-field is studied. With the equivalent orthotropic parameter obtained by the author, the corrugated shallow spherical shell is considered as an orthotropic shallow spherical shell, and geometrical nonlinearity and transverse shear deformation are taken into account. Nonlinear governing equations are obtained. The critical load is obtained using a modified iteration method. The effect of temperature variation and shear rigidity variation on stability is analyzed.

An improved time integration scheme based on uniform cubic B-splines and its application in structural dynamics

Weibin WEN, Hongshuai LEI, Kai WEI, Baosheng XU, Shengyu DUAN, Daining FANG

2017, 38(6):  889-908.  doi:10.1007/s10483-017-2207-8

摘要 ( 665 )   HTML   PDF (1030KB) ( 153 )  

参考文献 | 相关文章 | 多维度评价

A time integration algorithm for structural dynamic analysis is proposed by uniform cubic B-spline functions. The proposed algorithm is successfully used to solve the dynamic response of a single degree of freedom (SDOF) system, and then is generalized for a multiple-degree of freedom (MDOF) system. Stability analysis shows that, with an adjustable algorithmic parameter, the proposed method can achieve both conditional and unconditional stabilities. Validity of the method is shown with four numerical simulations. Comparison between the proposed method and other methods shows that the proposed method possesses high computation accuracy and desirable computation efficiency.