S.-A. B. Al Omari^1,2, E. Elnajjar¹

FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.2, pp. 91-109, 2013, DOI:10.3970/fdmp.2013.009.091

Abstract In a previous numerical study (Al Omari, Int. Communication in Heat and Mass Transfer, 2011) the heat transfer enhancement between two immiscible liquids with clear disparity in thermal conductivity such as water and a liquid metal (attained by co- flowing them in a direct contact manner alongside each other in mini channel) was demonstrated. The present work includes preliminary experimental results that support those numerical findings. Two immiscible liquids (hot water and liquid gallium) are allowed experimentally to exchange heat (under noflow conditions) in a stationary metallic cup where they are put in direct contact. The experimental results confirm the… More >

Emad Elnajjar¹, Mohammad O. Hamdan, Yousef Haik

FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.1, pp. 77-89, 2013, DOI:10.3970/fdmp.2013.009.077

Abstract In this paper, two heat transfer configurations (central-jet and side-jet) of jet impinging on a semicircular surface are experimentally studied. The internal channel is formed using flat insulated wall and a semi-circular surface using a curved flexible heater with a uniform heat flux. A set of experiments have been performed for the purpose of assessing the heat augmentation and pressure drop between the two jet configurations. The measurements include the inlet and outlet flow temperatures using thermocouples, the temperature map of the flexible heater using thermal infra-red camera, the flow rates using rotary meter and pressure drop using pressure transducer.… More >

Nadia Dihmani¹, Samir Amraqui¹, Ahmed Mezrhab^1,2, Najib Laraqi³

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.3, pp. 311-322, 2012, DOI:10.3970/fdmp.2012.008.311

Abstract Natural convection with surface radiation heat transfer is investigated numerically in a vented vertical channel heated asymmetrically. The numerical solution is obtained using a finite volume method based on the SIMPLER algorithm for the treatment of velocity-pressure coupling. Concerning the radiation exchange, in particular, the working fluid is assumed to be transparent, so that only the solid surfaces (assumed diffuse-grey) give a contribute to such exchange. The effect of Rayleigh numbers and rib width (for Pr=0.7 air fluid) on the heat transfer and flow structure in the channel is examined in detail. Results are presented in terms of isotherms, streamlines,… More >

Y. Amirouche¹, R. Bessaïh²

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.3, pp. 295-310, 2012, DOI:10.3970/fdmp.2012.008.295

Abstract This paper summarizes a series of computational results originating from the simulation of three-dimensional turbulent natural convection occurring in a vertical channel containing 5 cubic aluminum heated sources (mimicking a set of electronics components equally spaced in the vertical direction). A three-dimensional, conjugate heat transfer model with appropriate boundary conditions is used. In particular, the governing equations are solved by a finite volume method throughout the entire physical domain. Calculations are made for distinct values of: the Rayleigh number, the ratio (air/solid) of thermal conductivities and other geometrical parameters (in order to examine the influence of such variables on the… More >

F. Moufekkir¹, M.A. Moussaoui¹, A. Mezrhab^1,2, H. Naji^3,4, M. Bouzidi⁵

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.2, pp. 129-154, 2012, DOI:10.3970/fdmp.2012.008.129

Abstract The problem related to coupled double diffusive convection in a square enclosure filled with a gray gas in the presence of volumetric radiation is examined numerically. The horizontal walls are assumed to be insulated and impermeable. Different temperatures and species concentrations are imposed at vertical walls. In particular, we propose a 2-D numerical approach based on a hybrid scheme combining a multiple-relaxation-time lattice Boltzmann model (MRT-LBM) and a standard finite difference method (FDM). The radiative term in the energy equation is treated using the discrete ordinates method (DOM) with a S8 quadrature. The influence of various parameters (such as the… More >

A.K. Plappally¹, M.A.R. Sharif¹, R.C. Bradt²

FDMP-Fluid Dynamics & Materials Processing, Vol.3, No.2, pp. 115-128, 2007, DOI:10.3970/fdmp.2007.003.115

Abstract A novel physical chemical filtration process in a tundish for removal of inclusion particles from molten steel is proposed and analyzed. The considered inclusion particles are mainly composed of the minerals alumina (Al2O3 and spinel (MgAl2O4, which have an affinity to adhere (on contact) to an inclusion trap. An industrial tundish is considered and modified with a zigzag channel block insert installed across the molten steel flow so that when the molten steel flows through the zigzag channels, the inclusion particles are driven into contact with the channel surfaces by increased recirculation and turbulence. The inclusions will bond with the… More >

Na Lin¹, Jiacheng Tang¹, Xianwei Li^2,3, Liang Zhao^1,*

CMC-Computers, Materials & Continua, Vol.61, No.1, pp. 323-344, 2019, DOI:10.32604/cmc.2019.05674

Abstract Path planning algorithm is the key point to UAV path planning scenario. Many traditional path planning methods still suffer from low convergence rate and insufficient robustness. In this paper, three main methods are contributed to solving these problems. First, the improved artificial potential field (APF) method is adopted to accelerate the convergence process of the bat’s position update. Second, the optimal success rate strategy is proposed to improve the adaptive inertia weight of bat algorithm. Third chaos strategy is proposed to avoid falling into a local optimum. Compared with standard APF and chaos strategy in UAV path planning scenarios, the… More >

Sifan Long¹, Ming Zhao^2,*, Xinfu He³

CMC-Computers, Materials & Continua, Vol.58, No.3, pp. 727-760, 2019, DOI:10.32604/cmc.2019.04454

Abstract With the development of society and the exhaustion of fossil energy, researcher need to identify new alternative energy sources. Nuclear energy is a very good choice, but the key to the successful application of nuclear technology is determined primarily by the behavior of nuclear materials in reactors. Therefore, we studied the radiation performance of the fusion material reduced activation ferritic/martensitic (RAFM) steel. The main novelty of this paper are the statistical analysis of RAFM steel data sets through related statistical analysis and the formula derivation of the gradient descent method (GDM) which combines the gradient descent search strategy of the… More >

Zhaoyue Zhang^{1, *}, Jing Zhang², Peng Wang¹, Lei Chen³

CMC-Computers, Materials & Continua, Vol.57, No.1, pp. 151-166, 2018, DOI:10.32604/cmc.2018.02890

Abstract In order to explore the safe operation of UAVs in non-segregated airspace, a collision risk model for cylindrical UAVs based on conflict areas was constructed and the risk of conflict between manned and unmanned aerial vehicles was researched. According to the results of risk analysis, a strategy for solving the conflict of aircraft is proposed, and the risk assessment experiment of unmanned aerial vehicle (UAV) in non-isolated airspace conflict is carried out. The results show that under the experimental conditions, large unmanned aerial vehicles equipped with ADS-B, TCAS and other airborne sensing systems will indeed interfere with other aircraft in… More >

Mahesh S. Shinde^1,*, Kishor M. Ashtankar¹

CMC-Computers, Materials & Continua, Vol.54, No.3, pp. 287-306, 2018, DOI:10.3970/cmc.2018.054.287

Abstract Cooling system improvement is important in injection molding to get better quality and productivity. The aim of this paper was to compare the different shapes of the conformal cooling channels (CCC) with constant surface area and CCC with constant volume in injection molding using Mold-flow Insight 2016 software. Also the CCC results were compared with conventional cooling channels. Four different shapes of the CCC such as circular, elliptical, rectangular and semi-circular were proposed. The locations of the cooling channels were also kept constant. The results in terms of cooling time, cycle time reduction and improvement in quality of the product… More >