Bingzhu Wang^1,*, Xiangrui Ye^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 1401-1425, 2024, DOI:10.32604/cmes.2024.047364 - 29 January 2024

Abstract A novel three-dimensional-fiber reinforced soft pneumatic actuator (3D-FRSPA) inspired by crab claw and human hand structure that can bend and deform independently in each segment is proposed. It has an omni-directional bending configuration, and the fibers twined symmetrically on both sides to improve the bending performance of FRSPA. In this paper, the static and kinematic analysis of 3D-FRSPA are carried out in detail. The effects of fiber, pneumatic chamber and segment length, and circular air chamber radius of 3D-FRSPA on the mechanical performance of the actuator are discussed, respectively. The soft mobile robot composed of More >

Hongzhi Xu^1,2, Jian Wang^1,3, Shuxia Li^1,*, Fengrui Zhao¹, Chengwen Wang¹, Yang Guo¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.3, pp. 505-523, 2024, DOI:10.32604/fdmp.2023.030604 - 12 January 2024

Abstract Natural gas hydrate (NGH) is generally produced and accumulated together with the underlying conventional gas. Therefore, optimizing the production technology of these two gases should be seen as a relevant way to effectively reduce the exploitation cost of the gas hydrate. In this study, three types of models accounting for the coexistence of these gases are considered. Type A considers the upper hydrate-bearing layer (HBL) adjacent to the lower conventional gas layer (CGL); with the Type B a permeable interlayer exists between the upper HBL and the lower CGL; with the type C there is… More >

Shiyang Song^1,*, Tongxin Han²

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.1, pp. 127-145, 2024, DOI:10.32604/fdmp.2023.030137 - 08 November 2023

Abstract Aiming to mitigate the aerodynamic lift force imbalance between pantograph strips, which exacerbates wear and affects the current collection performance of the pantograph-catenary system, a study has been conducted to support the beam deflector optimization using a combination of experimental measurements and computational fluid dynamics (CFD) simulations. The results demonstrate that the size, position, and installation orientation of the wind deflectors significantly influence the amount of force compensation. They also indicate that the front strip deflectors should be installed downwards and the rear strip deflectors upwards, thereby forming a “π” shape. Moreover, the lift force More >

Ayad S. Abedalh^*, Sohaib Hassan Mohammed

Frontiers in Heat and Mass Transfer, Vol.21, pp. 227-243, 2023, DOI:10.32604/fhmt.2023.041777 - 30 November 2023

Abstract Solar energy, a renewable resource, can be harnessed instead of fossil fuels to generate power and heat. One effective method for converting solar energy into heat is through a solar air heating (SAH) system. The theoretical investigation focused on the thermal performance of various V-groove angles on a corrugated absorber plate. The researchers maintained the exterior dimensions and constraints of the absorber plate while increasing its surface area by using a corrugated absorber surface. For the simulation, three different V-groove angles were employed: 45°, 30°, and 15°. The temperature and air flow rate into the… More > Graphic Abstract

Amnart Boonloi¹, Withada Jedsadaratanachai^2,*

Frontiers in Heat and Mass Transfer, Vol.21, pp. 317-336, 2023, DOI:10.32604/fhmt.2023.044929 - 30 November 2023

Abstract Thermal performance enhancement in a square channel heat exchanger (HX) using a passive technique is presented. Vortex turbulator insertion in a square channel HX as a passive technique is selected for thermal improvement. The vortex turbulator of interest is discrete X-V baffles (XVB). The discrete XVBs are inserted in the square channel with the main aim of generating vortex flow. The vortex flow generated can support the enhanced convective heat transfer coefficient and also enhance HX performance. Effects of baffle configuration (type A and B), baffle size (w/H = 0.05, 0.10, 0.15 and 0.20), baffle… More > Graphic Abstract

Meng Jia, Mingjun Pang^*

Frontiers in Heat and Mass Transfer, Vol.21, pp. 337-366, 2023, DOI:10.32604/fhmt.2023.044286 - 30 November 2023

Abstract The interphase mass, heat transfer efficiency, and flow resistance are strongly dependent on bubble size in gasliquid two-phase systems, so it is very important for engineering applications to effectively control bubble size. In this paper, the formation, growth, and detachment of single bubbles in Newtonian liquids based on capillary needles were studied in detail using a volume of fluid method. The authors investigated the effects of gas injection velocity, gravitational level, surface tension coefficient, needle radius, and liquid−phase properties (liquid viscosity and density) on the process of bubble generation, and the effects of the above… More >

Abdourahamane Salifou Adam¹, Hatem Mrad¹, Haykel Marouani^2,*, Yasser Fouad³

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.3, pp. 2845-2865, 2023, DOI:10.32604/cmes.2023.030777 - 03 August 2023

Abstract A high percentage of failure in pump elements originates from fatigue. This study focuses on the discharge section behavior, made of ductile iron, under dynamic load. An experimental protocol is established to collect the strain under pressurization and depressurization tests at specific locations. These experimental results are used to formulate the ultimate pressure expression function of the strain and the lateral surface of the discharge section and to validate finite element modeling. Fe-Safe is then used to assess the fatigue life cycle using different types of fatigue criteria (Coffin-Manson, Morrow, Goodman, and Soderberg). When the… More >

Dongxiao Zhang¹, Lin Lu^1,*, Xiaobin Qi^2,3, Xuepu Yan¹, Cisong Gao¹, Yanxiao Hu¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.10, pp. 2707-2728, 2023, DOI:10.32604/fdmp.2023.028641 - 25 June 2023

Abstract A two-dimensional model, employing a dynamic mesh technology, is used to simulate numerically the transient multiphase flow field produced by two submerged parallel guns. After a grid refinement study ensuring grid independence, five different conditions are considered to assess the evolution of cavitation occurring in proximity to the gun muzzle. The simulation results show that flow interference is enabled when the distance between the parallel barrels is relatively small; accordingly, the generation and evolution of the vapor cavity becomes more complex. By means of the Q criterion for vorticity detection, it is shown that cavitation More >

Mohammad Aslefallah¹, Şuayip Yüzbaşi², Saeid Abbasbandy^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.2, pp. 1687-1706, 2023, DOI:10.32604/cmes.2023.025647 - 06 February 2023

Abstract In this work, the exponential approximation is used for the numerical simulation of a nonlinear SITR model as a system of differential equations that shows the dynamics of the new coronavirus (COVID-19). The SITR mathematical model is divided into four classes using fractal parameters for COVID-19 dynamics, namely, susceptible (S), infected (I), treatment (T), and recovered (R). The main idea of the presented method is based on the matrix representations of the exponential functions and their derivatives using collocation points. To indicate the usefulness of this method, we employ it in some cases. For error More > Graphic Abstract

Nisrine Hanchi^*, Hamid Hamza, Jawad Lahjomri, Khalid Zniber, Abdelaziz Oubarra

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.5, pp. 1227-1236, 2023, DOI:10.32604/fdmp.2023.022530 - 30 November 2022

Abstract The work deals with the thermal behavior of a conventional partition wall incorporating a phase change material (PCM). The wall separates two environments with different thermal properties. The first one is conditioned, while the adjacent space is characterized by a temperature that changes sinusoidally in time. The effect of the PCM is assessed through a comparative analysis of the cases with and without PCM. The performances are evaluated in terms of dimensionless energy stored within the wall, comfort temperature and variations of these quantities as a function of the amount of PCM and its emplacement. More >