Tounsi Chati^a,* , Kouider Rahmani^b, Toufik Tayeb Naas^c, Abdelkader Rouibah^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-11, 2022, DOI:10.5098/hmt.18.19

Abstract Numerical results of turbulent natural convection and mass transfer in an open enclosure for different aspect ratios (AR = 0.5, 1, and 2) with a humidair are carried out. Mass fraction and local Nusselt number were proposed to investigate the heat and mass transfer. A heat flux boundary conditions were subjected to the lateral walls and the bottom one make as an adiabatic wall, while the top area was proposed as a free surface. Effect of Rayleigh numbers (10⁶ ≤ More >

Mousa Aqeel Ali^*, Saad Najeeb Sheha^b

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-10, 2022, DOI:10.5098/hmt.19.39

Abstract In this study, the hydrothermal water flow characteristics using a dimpled inner tube heat exchanger are investigated experimentally and numerically. A numerical analysis has performed on two types of dimpled tubes (In-lined and staggered distributions) for two distribution angles 60o and 90o , and two dimple diameters(4 mm and 6 mm) with constant pitch ratio (X/d=8). In experimental part, a staggered arrangement dimpled inner tube distribution with angle 60o , dimple diameter of 6 mm and constant pitch ratio (X/d=8)is used as well as plain tube. The results illustrate that the heat transfer as Nusselt More >

D. Ribeiro^1,*, B. Costa², P. Montenegro², R. Calçada²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.24, No.1, pp. 1-1, 2022, DOI:10.32604/icces.2022.08682

Abstract The present article focuses on the evaluation of the dynamic behaviour of a centenary steel arch bridge, located in Portugal, under light railway traffic loads. The work aims to assess the dynamic behaviour of the bridge subjected to an alternative type of railway vehicle, more specifically, a typical underground vehicle that is currently in service in the Lisbon Metro. The dynamic response of the system has been evaluated using two distinct methodologies, namely a moving loads model and a vehicle-bridge interaction model. To achieve this goal, finite element (FE) models from both the bridge and… More >

Hossein Bisheh^1,2, Yunhua Luo^1,3, Timon Rabczuk^2,*

CMC-Computers, Materials & Continua, Vol.71, No.1, pp. 1349-1369, 2022, DOI:10.32604/cmc.2022.018262 - 03 November 2021

Abstract Various parameters such as age, height, weight, and body mass index (BMI) influence the hip fracture risk in the elderly which is the most common injury during the sideways fall. This paper presents a parametric study of hip fracture risk based on the gender, age, height, weight, and BMI of subjects using the subject-specific QCT-based finite element modelling and simulation of single-leg stance and sideways fall loadings. Hip fracture risk is estimated using the strain energy failure criterion as a combination of bone stresses and strains leading to more accurate and reasonable results based on More >

Suliman A. Alsuhibany^*, Hessah Abdulaziz Alhodathi

Intelligent Automation & Soft Computing, Vol.31, No.1, pp. 523-537, 2022, DOI:10.32604/iasc.2022.019913 - 03 September 2021

Abstract The Completely Automated Public Turing test to tell Computers and Humans Apart (CAPTCHA) technique has been an interesting topic for several years. An Arabic CAPTCHA has recently been proposed to serve Arab users. Since there have been few scientific studies supporting a systematic design or tuning for users, this paper aims to analyze the Arabic text-based CAPTCHA at the parameter level by conducting an experimental study. Based on the results of this study, we propose an Arabic text-based CAPTCHA scheme with Fast Gradient Sign Method (FGSM) adversarial images. To evaluate the security of the proposed More >

Fabio Bruzzone, Cristiana Delprete, Carlo Rosso^*

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.1, pp. 51-64, 2020, DOI:10.32604/cmes.2020.011023 - 18 September 2020

Abstract This paper is focused on finite element simulation of cylinder head gaskets. Finite element codes support several methodologies, each of which has its own strengths and weaknesses. One of the key points lies in the influence of the gasket geometry on its final behaviour. Such a contribution can come from the detailed modelling of the gasket or by defining a global non-linear behaviour in which material and geometry non-linearities are summarised. Two approaches were used to simulate the gasket behaviour. The first one consists in using a 2D approach, which allows to model through-thickness non-linear More >

F.C.C. Almeida^a , P.M. da Silva^b,c, M.N.C. Coelho Pinheiro^a,d,*

Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-9, 2019, DOI:10.5098/hmt.12.16

Abstract In the last decades, polymeric systems were essayed and applied successfully as vehicles for transdermal delivery devices of active principles. Applications in contraception, pain control, and smoking cessation are already frequent. A crucial aspect in the development of new formulations is the maintenance of the therapeutic drug concentration range for long periods. Recognizing this topic as interesting and challenging, simple models to describe drug release from a transdermal device were developed with the purpose to perform a parametric sensitivity analysis. Assuming drug diffusion within the polymeric delivery system as the dominant mechanism the models were More >

Mohd. Ahmed^1,*, Mohamed Hechmi El Ouni¹, Devinder Singh², Nabil Ben Kahla¹

CMES-Computer Modeling in Engineering & Sciences, Vol.121, No.2, pp. 687-786, 2019, DOI:10.32604/cmes.2019.06886

Abstract The paper presents a parametric study on interpolation techniques based postprocessed error estimation in finite element elastic analysis by varying important parameters of recovery, interpolation scheme and type of patch construction. The quality of error estimation with recovery parameters is compared in terms of local and global effectivity of error estimation, rate of error convergence, and adaptively refined meshes. A mesh free moving least square interpolation technique with proven reliability and effectivity is introduced for improving the recovery of finite element solution errors. The post-processed finite element solutions of elastic problems are presented for performance More >

Yuan Chen¹, Honggang Duan¹, Fei Yu¹, Xingyu Zhao¹, Han Xu¹, Jun Gao^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.11, No.2, pp. 127-142, 2015, DOI:10.3970/fdmp.2015.011.127

Abstract The dynamics of dispersed bubbles in a centrifugal separator are investigated with the aim to improve the efficiency of the system. The prototype separator consists of a rotor, a base, a diverting disc, a shaft, an oil trapping impeller, a central pipe, an inlet section for contaminated oil, an outlet section for purified oil and an air outlet. A hydrodynamic model is developed to predict the complex influence of parameters such as the centrifugal force and vacuum pressure. In particular, three different force models are selected to analyze the effect of the added mass and More >

Yongsheng Lian ¹

CMES-Computer Modeling in Engineering & Sciences, Vol.72, No.1, pp. 1-16, 2011, DOI:10.3970/cmes.2011.072.001

Abstract In this paper we simulate the unsteady, incompressible, and laminar flow behavior over a flat plate with round leading and trailing edges. A pressure-Poisson method is used to solve the incompressible Navier-Stokes equations. Both convection and diffusion terms are discretized using a second-order accurate central difference method. A second-order accurate split-step scheme with an Adam's predictor corrector time-stepping method is adopted for the time integration. An overlapping moving grid approach is employed to dynamically update the grid due to the plate motion. The effects of the pitch rate, Reynolds number, location of pitch axis, and More >