Haitao Liu^1,2,*, Jiaming Wang¹, Xiuliang Zhang¹, Yanji Jiang², Qian Xiao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 2747-2772, 2024, DOI:10.32604/cmes.2024.047129 - 11 March 2024

Abstract The expansion chamber serves as the primary silencing structure within the exhaust pipeline. However, it can also act as a sound-emitting structure when subjected to airflow. This article presents a hybrid method for numerically simulating and analyzing the unsteady flow and aerodynamic noise in an expansion chamber under the influence of airflow. A fluid simulation model is established, utilizing the Large Eddy Simulation (LES) method to calculate the unsteady flow within the expansion chamber. The simulation results effectively capture the development and changes of the unsteady flow and vorticity inside the cavity, exhibiting a high… More > Graphic Abstract

Shijun Zhao¹, Qing Zhang², Yusong Miao¹, Weizhao Zhang³, Xinbo Zhao¹, Wei Xu^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 3167-3187, 2024, DOI:10.32604/cmes.2023.045015 - 11 March 2024

Abstract The surrounding rock of roadways exhibits intricate characteristics of discontinuity and heterogeneity. To address these complexities, this study employs non-local Peridynamics (PD) theory and reconstructs the kernel function to represent accurately the spatial decline of long-range force. Additionally, modifications to the traditional bond-based PD model are made. By considering the micro-structure of coal-rock materials within a uniform discrete model, heterogeneity characterized by bond random pre-breaking is introduced. This approach facilitates the proposal of a novel model capable of handling the random distribution characteristics of material heterogeneity, rendering the PD model suitable for analyzing the deformation… More >

Zhengrong Shi^1,3, Jie Ren¹, Tao Zhang^1,3,*, Yanming Shen^2,*

Energy Engineering, Vol.121, No.3, pp. 681-702, 2024, DOI:10.32604/ee.2023.045238 - 27 February 2024

Abstract Building energy consumption and building carbon emissions both account for more than 20% of their total national values in China. Building employing phase change material (PCM) for passive temperature control shows a promising prospect in meeting the comfort demand and reducing energy consumption simultaneously. However, there is a lack of more detailed research on the interaction between the location and thickness of PCM and indoor natural convection, as well as indoor temperature distribution. In this study, the numerical model of a passive temperature-controlled building integrating the developed PCM module is established with the help of… More > Graphic Abstract

Peng Qiao¹, Shuangshuang Lan^1,*, Hongbiao Gu², Zhengtan Mao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 1381-1399, 2024, DOI:10.32604/cmes.2023.045662 - 29 January 2024

Abstract Based on global initiatives such as the clean energy transition and the development of renewable energy, the pumped storage power station has become a new and significant way of energy storage and regulation, and its construction environment is more complex than that of a traditional reservoir. In particular, the stability of the rock strata in the underground reservoirs is affected by the seepage pressure and rock stress, which presents some challenges in achieving engineering safety and stability. Using the advantages of the numerical simulation method in dealing deal with nonlinear problems in engineering stability, in… More > Graphic Abstract

Peilei Yan^1,2,*, Endong Guo^1,2, Houli Wu^1,2, Liangchao Zhang^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 1655-1678, 2024, DOI:10.32604/cmes.2023.044760 - 29 January 2024

Abstract A coupled numerical calculation method combining smooth particle hydrodynamics (SPH) and the finite element method (FEM) was implemented to investigate the seismic response of horizontal storage tanks. A numerical model of a horizontal storage tank featuring a free liquid surface under seismic action was constructed using the SPH–FEM coupling method. The stored liquid was discretized using SPH particles, while the tank and supports were discretized using the FEM. The interaction between the stored liquid and the tank was simulated by using the meshless particle contact method. Then, the numerical simulation results were compared and analyzed… More >

Wei Zhong¹, Zhenfang Xin², Lihua Wang^1,*, Haiping Liu²

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 1427-1453, 2024, DOI:10.32604/cmes.2023.031271 - 29 January 2024

Abstract Flash boiling atomization (FBA) is a promising approach for enhancing spray atomization, which can generate a fine and more evenly distributed spray by increasing the fuel injection temperature or reducing the ambient pressure. However, when the outlet speed of the nozzle exceeds 400 m/s, investigating high-speed flash boiling atomization (HFBA) becomes quite challenging. This difficulty arises from the involvement of many complex physical processes and the requirement for a very fine mesh in numerical simulations. In this study, an HFBA model for gasoline direct injection (GDI) is established. This model incorporates primary and secondary atomization,… More >

Wei Guo¹, Yanliang Liu¹, Xuqiang Wang¹, Jiazheng Meng², Mengqin Hu², Bo He^2,*

Structural Durability & Health Monitoring, Vol.18, No.1, pp. 19-35, 2024, DOI:10.32604/sdhm.2023.042944 - 11 January 2024

Abstract As an important lightning protection device in substations, lightning rods are susceptible to vibration and potential structural damage under wind loads. In order to understand their vibration mechanism, it is necessary to conduct flow analysis. In this study, numerical simulations of the flow field around a 330 kV cylindrical lightning rod with different diameters were performed using the SST k-ω model. The flow patterns in different segments of the lightning rod at the same reference wind speed (wind speed at a height of 10 m) and the flow patterns in the same segment at different reference wind… More >

Zongjun Yin^*, Rong Su, Hui Xu

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.3, pp. 487-504, 2024, DOI:10.32604/fdmp.2023.042631 - 12 January 2024

Abstract In this study, numerical simulations of the pinching-off phenomena displayed by the dispersed phase in a continuous phase have been conducted using COMSOL Multiphysics (level-set method). Four flow patterns, namely “drop flow”, “jet flow”, “squeeze flow”, and “co-flow”, have been obtained for different flow velocity ratios, channel diameter ratios, density ratios, viscosity ratios, and surface tension. The flow pattern map of two-phase flow in coaxial microchannels has been obtained accordingly, and the associated droplet generation process has been critically discussed considering the related frequency, diameter, and pinch-off length. In particular, it is shown that the More > Graphic Abstract

Peiheng He, Jiye Zhang^*, Lan Zhang, Jiaqi Wang, Yuzhe Ma

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.1, pp. 937-953, 2024, DOI:10.32604/cmes.2023.043700 - 30 December 2023

Abstract The running stability of high-speed train is largely constrained by the wheel-rail coupling relationship, and the continuous wear between the wheel and rail surfaces will profoundly affect the dynamic performance of the train. In recent years, under the background of increasing train speed, some scientific researchers have proposed a new idea of using the lift force generated by the aerodynamic wings (aero-wing) installed on the roof to reduce the sprung load of the carriage in order to alleviate the wear and tear of the wheel and rail. Based on the bidirectional running characteristics of high-speed… More >

Huihui Zhai¹, Dongqi Jiao², Haichao Zhou^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.1, pp. 955-975, 2024, DOI:10.32604/cmes.2023.043322 - 30 December 2023

Abstract The wheels have a considerable influence on the aerodynamic properties and can contribute up to 25% of the total drag on modern vehicles. In this study, the effect of the wheel spoke structure on the aerodynamic performance of the isolated wheel is investigated. Subsequently, the 35° Ahmed body with an optimized spoke structure is used to analyze the flow behavior and the mechanism of drag reduction. The Fluent software is employed for this investigation, with an inlet velocity of 40 m/s. The accuracy of the numerical study is validated by comparing it with experimental results obtained… More >