M. Kriaa¹, M. El Alami^1,2, M. Najam¹, E. Semma³

FDMP-Fluid Dynamics & Materials Processing, Vol.7, No.2, pp. 125-140, 2011, DOI:10.3970/fdmp.2011.007.125

Abstract In this paper a numerical study of natural convection in a two dimensional convergent channel, with or without rectangular block, is carried out. The block is placed at the channel outlet and its thermal conductivity is set equal to that of air. One of channel planes is heated at constant temperature T_H. The other one is maintained cold at T_C < T_H. The governing equations are solved using a finite volume method and the SIMLEC algorithm for the velocity-pressure coupling is used. Special emphasis is given to detail the effect of the block size and Rayleigh number on the dynamics… More >

R. Mestiri¹, R.Hadaji¹, S. Ben Nasrallah¹

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.4, pp. 409-418, 2010, DOI:10.3970/fdmp.2010.006.409

Abstract The electroaerodynamic actuator or plasma actuator uses the characteristics of the non-thermal surface plasmas. These plasmas are created in atmospheric pressure by a DC electrical corona discharge at the surface of a dielectric material. The two electrodes are two conductive parallel wires. The applied voltage is of several kilovolts. The corona discharge creates a tangential electric wind that can modify the boundary layer flow properties. In this paper, we present the results found for two geometric configurations: the flat plate and the cylinder. In order to study the discharge specificity, we have found the current- voltage characteristics for different inter-electrode… More >

G. P. Russo¹, A. Esposito¹, B. Esposito², R. Renis^1,1, F. Parente¹

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.3, pp. 319-336, 2010, DOI:10.3970/fdmp.2010.006.319

Abstract A low-cost facility, able to simulate icing conditions occurring in flight, has been built via modification of a small blow-down supersonic wind tunnel. As the storage tank (30bar) is emptied through the wind tunnel, expansion of the contained air makes temperature to decrease down to -20 C and a control valve holds such temperature for about 200s. In order to increase the liquid water content (LWC) of the flow allowing ice formation on model surfaces within the test chamber, water is sprayed in the stream within the stagnation chamber by means of a controlled spray gun. This unsteady technique allows… More >

Lili He^1,2, Hongtao Bai^1,2, Dantong Ouyang^1,2, Changshuai Wang^1,2, Chong Wang^1,2,3, Yu Jiang^1,2,*

CMC-Computers, Materials & Continua, Vol.60, No.2, pp. 599-613, 2019, DOI:10.32604/cmc.2019.05928

Abstract Cloud-derived wind refers to the wind field data product reversely derived through satellite remote sensing cloud images. Satellite cloud-derived wind inversion has the characteristics of large scale, computationally intensive and long time. The most widely used cloud-derived serial--tracer cloud tracking method is the maximum cross-correlation coefficient (MCC) method. In order to overcome the efficiency bottleneck of the cloud-derived serial MCC algorithm, we proposed a parallel cloud-derived wind inversion algorithm based on GPU framework in this paper, according to the characteristics of independence between each wind vector calculation. In this algorithm, each iteration is considered as a thread of GPU cores,… More >

Lan Sun¹, Chen Ge¹, Xin Huang¹, Yingjie Wu^1,*, Yan Gao²

CMC-Computers, Materials & Continua, Vol.58, No.1, pp. 61-78, 2019, DOI:10.32604/cmc.2019.03744

Abstract Continuous response of range query on steaming data provides useful information for many practical applications as well as the risk of privacy disclosure. The existing research on differential privacy streaming data publication mostly pay close attention to boosting query accuracy, but pay less attention to query efficiency, and ignore the effect of timeliness on data weight. In this paper, we propose an effective algorithm of differential privacy streaming data publication under exponential decay mode. Firstly, by introducing the Fenwick tree to divide and reorganize data items in the stream, we achieve a constant time complexity for inserting a new item… More >

X.P. Shen, A. Diaz¹, T. Sheehy²

CMC-Computers, Materials & Continua, Vol.20, No.3, pp. 205-224, 2010, DOI:10.3970/cmc.2010.020.205

Abstract This paper presents a case study for the design of a mud-weight window (MWW) with three-dimensional (3-D), finite-element (FE) tools for subsalt wells. The trajectory of the target well penetrates a 7 km thick salt body. A numerical scheme has been proposed for calculating the shear failure gradient (SFG) and fracture gradient (FG) with 3-D FE software. User subroutines have been developed to address non-uniform pore-pressure distribution. A series of FE calculations were performed to obtain the MWW of the target wellbore, which consists of the SFG and FG for the subsalt sections. Although no reverse faulting structure exists in… More >

Jun Xu^1,2, Yibing Li¹, Xi Chen^2,3, Yuan Yan^2,3, Dongyun Ge^4,1, Bohan Liu¹

CMC-Computers, Materials & Continua, Vol.18, No.2, pp. 183-212, 2010, DOI:10.3970/cmc.2010.018.183

Abstract The crack pattern in a PVB laminated windshield upon head impact is of considerable interest because it contains important information on energy mitigation, pedestrian protection, and accident reconstruction. We carry out a systematic numerical study based on the extended finite element method (XFEM), to investigate the effects of various material and system variables, including the impact speed, effective head mass, PVB interlayer material thickness and property, windshield curvature, aspect ratio and size, boundary constraint, impact angle and off-center impact, on the parameters characterizing the resulting crack pattern, i.e. the crack length, crack angle and circumferential crack shape. General relations bridging… More >