Yuanjun Dai^1,2, Jingan Cui¹, Baohua Li^1,*, Cong Wang¹, Kunju Shi¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.4, pp. 771-786, 2024, DOI:10.32604/fdmp.2023.029584

Abstract A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient, lift coefficient, and drag coefficient. The numerical results demonstrate that the flap can effectively improve the lift coefficient of the airfoil; however, at small attack angles, its influence is significantly reduced. When the angle of attack exceeds the critical stall angle and the flap height is 1.5% of the chord length, the influence of the flap becomes very evident. As the flap height… More >

Xuhui Jiang¹, Xi Zhang¹, Song Wang¹, Ruiqiong Wang¹, Peng Zou¹, Jingzhou Lu², Xiaoxiao Li^2,*

Frontiers in Heat and Mass Transfer, Vol.22, No.1, pp. 193-216, 2024, DOI:10.32604/fhmt.2023.046832

Abstract This study investigates the performance of a natural draft dry cooling tower group in crosswind conditions through numerical analysis. A comprehensive three-dimensional model is developed to analyze the steady-state and dynamic behavior of the towers. The impact of wind speed and direction on heat rejection capacity and flow patterns is examined. Results indicate that crosswinds negatively affect the overall heat transfer capacity, with higher crosswind speeds leading to decreased heat transfer. Notably, wind direction plays a significant role, particularly at 0°. Moreover, tower response time increases with higher crosswind speeds due to increased turbulence and the formation of vortices. The… More >

Fayi Yan^*, Xuejian Pei, He Lu, Shuzhen Zong

Frontiers in Heat and Mass Transfer, Vol.22, No.1, pp. 287-304, 2024, DOI:10.32604/fhmt.2023.045038

Abstract As compact and efficient heat exchange equipment, helically coiled tube-in-tube heat exchangers (HCTT heat exchangers) are widely used in many industrial processes. However, the thermal-hydraulic research of liquefied natural gas (LNG) as the working fluid in HCTT heat exchangers is rarely reported. In this paper, the characteristics of HCTT heat exchangers, in which LNG flows in the inner tube and ethylene glycol-water solution flows in the outer tube, are studied by numerical simulations. The influences of heat transfer characteristics and pressure drops of the HCTT heat transfers are studied by changing the initial flow velocity, the helical middle diameter, and… 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

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 compensation provided by the wind… More >

Shiyue Zhang¹, Xue Song^1,2, Jingying Wang^1,*, Wen Huang^3,*, Yue Zhou⁴, Mingrui Li¹

Molecular & Cellular Biomechanics, Vol.20, No.2, pp. 81-94, 2023, DOI:10.32604/mcb.2023.044445

Abstract Pulmonary embolism (PE), caused by deep venous thrombosis (DVT), is a disease with high morbidity and mortality. Implantation of inferior vena cava filters is an important method for the clinical prevention of PE. The hemodynamic characteristics of filters implanted in the inferior vena cava (IVC) have a significant impact on their performance. However, IVC diameters vary among patients. This may have a direct impact on the hemodynamic properties of the filter. At present, there is no research on this kind of problem to be investigated. In this paper, the hemodynamic properties of the VenaTech convertible filter were simulated in three… More > Graphic Abstract

Dawei Liu, Zhiwei Jin, Xin Peng^*, Gang Liu, Yue Zhang

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.3, pp. 2691-2713, 2023, DOI:10.32604/cmes.2023.026048

Abstract The large dual-channel wide-bodied aircraft has a long range and a high cruise Mach number. Therefore, its aerodynamic design requires a high level of wind tunnel test refinement. Based on the requirements of aerodynamic design for the future wide-bodied aircraft and the characteristics of high-speed wind tunnel tests, the error theory is introduced to analyze the factors affecting the accuracy of the test data. This study carries out a series of research on the improvement of refined aerodynamic test technology in an FL-26 wind tunnel, including design and optimization of the support system of wide-bodied aircraft, model attitude angle measurement,… More >

Hongtao Guo, Changrong Zhang, Binbin Lv, Li Yu^*

CMES-Computer Modeling in Engineering & Sciences, Vol.132, No.3, pp. 991-1010, 2022, DOI:10.32604/cmes.2022.020638

Abstract The static aeroelastic effect of aircraft ailerons with high aspect ratio at transonic velocity is investigated in this paper by the CFD/CSD fluid-structure coupling numerical simulation. The influences of wing static aeroelasticity and the ‘scissor opening’ gap width between aileron control surface and the main wing surface on aileron efficiency are mainly explored. The main purpose of this paper is to provide technical support for the wind tunnel experimental model of aileron static aeroelasticity. The results indicate that the flight dynamic pressure has a great influence on the static aeroelastic effect of ailerons, and the greater the dynamic pressure, the… More >

Yanbin Tan¹, Xingwen He^1,*, Lei Shi², Shi Zheng³, Zhe Zhang¹, Xinshan Wang²

CMES-Computer Modeling in Engineering & Sciences, Vol.131, No.2, pp. 1041-1061, 2022, DOI:10.32604/cmes.2022.018543

Abstract To numerically evaluate the reinforcement effect on dynamic characteristics of a concrete-filled steel tube arch bridge with vibration problems, a 12-degree-of-freedom sprung-mass dynamic vehicle model and a 3D finite element bridge model were established. Then, the coupled equations of vehicle-bridge interaction were derived and a computer program was developed using the FORTRAN language. This program can accurately simulate vehicle-bridge coupled vibration considering the bumping effect and road surface irregularity during motion of the vehicle. The simulated results were compared with those of relevant literatures to verify the correctness of the self-developed program. Then, three reinforcement schemes for the bridge (Addition… More >

Xu Li¹, Ying Yan², Shuai Shao³, Shunying Ji^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.2, pp. 645-671, 2021, DOI:10.32604/cmes.2021.013674

Abstract Considering the interaction between a sleeper, ballast layer, and substructure, a three-dimensional coupled discrete-finite element method for a ballasted railway track is proposed in this study. Ballast granules with irregular shapes are constructed using a clump model using the discrete element method. Meanwhile, concrete sleepers, embankments, and foundations are modelled using 20-node hexahedron solid elements using the finite element method. To improve computational efficiency, a GPU-based (Graphics Processing Unit) parallel framework is applied in the discrete element simulation. Additionally, an algorithm containing contact search and transfer parameters at the contact interface of discrete particles and finite elements is developed in… More >

Chongfei Sun¹, Jianzhong Shang¹, Zirong Luo¹, Xin Li^2,*, Zhongyue Lu¹, Guoheng Wu¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.6, pp. 1147-1159, 2020, DOI:10.32604/fdmp.2020.09937

Abstract Small moving vehicles represent an important category of marine engineering tools and devices (equipment) typically used for ocean resource detection and maintenance of marine rights and interests. The lack of efficient power supply modes is one of the technical bottlenecks restricting the effective utilisation of this type of equipment. In this work, the performance characteristics of a new type of elastic-blade/wave-energy converter (EBWEC) and its core energy conversion component (named wave energy absorber) are comprehensively studied. In particular, computational fluid dynamics (CFD) simulations and experiments have been used to analyze the hydrodynamics and performance characteristics of the EBWEC. The pressure… More >