Youxin Li^*

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.6, pp. 1129-1145, 2020, DOI:10.32604/fdmp.2020.09437 - 17 December 2020

Abstract In order to explore the impact of different structural design parameters and environmental factors on the performance of the hydrostatic guide rail, the flow field inside its oil chamber is simulated, which provides direction and guidance for the design and optimization of the guide rail system. Based on the theory of fluid lubrication and the Reynolds equation, numerical simulations are performed through a mathematical model. The results suggest that the bearing capacity of the oil film increases with the oil supply pressure. The film thickness and the film stiffness share a positive correlation. Different oil More >

Xiaorui Cheng^1,2,*, Yimeng Jiang¹, Min Li¹, Shuyan Zhang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 1047-1061, 2020, DOI:10.32604/fdmp.2020.010695 - 09 October 2020

Abstract The influence of the axial mount position of the guide vane on the pressure fluctuation in a nuclear pump (AP1000) is investigated. The characteristics of the three-dimensional flow inside the nuclear pump are analyzed by means of numerical simulation. Results indicate that when the axial relative distance between the guide vane and the pumping chamber is reduced, in conditions of “small flow,” the efficiency of the pump increases, the pressure inside the pumping chamber decreases, while the losses related to the guide vane grow. Under large flow conditions, as the efficiency of the pump decreases, More >

Miao He^1,2, Yihang Zhang^1,*, Mingbiao Xu^1,2,*, Jun Li³

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 1031-1046, 2020, DOI:10.32604/fdmp.2020.011145 - 09 October 2020

Abstract This study presents a new multiphase flow model with transient heat transfer and pressure coupling to simulate HTHP (high temperature and high pressure) sour gas “kicks” phenomena. The model is intended to support the estimation of wellbore temperature and pressure when sour gas kicks occur during drilling operation. The model considers sour gas solubility, phase transition and effects of temperature and pressure on the physical parameters of drilling fluid. Experimental data for a large-diameter pipe flow are used to validate the model. The results indicate that with fluid circulation, the annulus temperature with H₂S kicks is… More >

Xiaobin Shu, Miaomiao Ren^*

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 1019-1029, 2020, DOI:10.32604/fdmp.2020.09564 - 09 October 2020

Abstract In order to address typical problems due to the huge demand of oil for consumption in traditional internal combustion engines, a new more efficient combustion mode is proposed and studied in the framework of Computational Fluid Dynamics (CFD). Moreover, a Non-dominated Sorting Genetic Algorithm (NSGA-II) is applied to optimize the related parameters, namely, the engine methanol ratio, the fuel injection time, the initial temperature, the Exhaust Gas Re-Circulation (EGR) rate, and the initial pressure. The so-called Conventional Diesel Combustion (CDC), Homogeneous Charge Compression Ignition (HCCI) and the Reactivity Controlled Compression Ignition (RCCI) combustion modes are… More >

Lingzhi Yu¹, Yunqing Gu^1,*, Jiegang Mou¹, Denghao Wu¹, Zhenfu Chen², Yun Ren³

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 1007-1018, 2020, DOI:10.32604/fdmp.2020.09509 - 09 October 2020

Abstract In order to improve the performances of a cycloid gerotor pump, the variations of the radial force induced by different rotating speeds and outlet pressures are analyzed numerically. Using the numerical simulations as a basis, an improved oil inlet and outlet groove structure is proposed. The results show that the radial force decreases with the decrease of the outlet pressure and of the rotor speed. Compared with the original model, the large-end oil inlet line and pressure line of the new oil groove are claw-shaped. This configuration can effectively weaken the pressure changes inside the More >

Minxuan Li¹, Jing Sun^1,*, Dehua Liu¹, Yang Li¹, Kuidong Li², Wei Liu², Jialin Xiao², Jiani Hu³

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 993-1005, 2020, DOI:10.32604/fdmp.2020.010443 - 09 October 2020

Abstract Existing “evaluation indicators” are selected and combined to build a model to support the optimization of shale gas horizontal wells. Towards this end, different “weighting methods”, including AHP and the so-called entropy method, are combined in the frame of the game theory. Using a relevant test case for the implementation of the model, it is shown that the horizontal section of the considered well is in the middle sweet spot area with good physical properties and fracturing ability. In comparison with the FSI (flow scanner Image) gas production profile, the new model seems to display More >

Miaomiao Ren^*, Xiaobin Shu

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 979-991, 2020, DOI:10.32604/fdmp.2020.09563 - 09 October 2020

Abstract A novel algorithm is proposed for the simulation of fluid-structure interaction problems. In particular, much attention is paid to natural phenomena such as debris flow. The fluid part (debris flow fluid) is simulated in the framework of the smoothed particle hydrodynamics (SPH) approach, while the solid part (downstream obstacles) is treated using the finite element method (FEM). Fluid-structure coupling is implemented through dynamic boundary conditions. In particular, the software “TensorFlow” and an algorithm based on Python are combined to conduct the required calculations. The simulation results show that the dynamics of viscous and non-viscous debris More >

Yunfei Liao^1,*, Jin Liu²

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 961-977, 2020, DOI:10.32604/fdmp.2020.09163 - 09 October 2020

Abstract In order to improve the convective heat transfer relating to an eddy current retarder, the finite element model has been used to assess the performances of different possible designs. In particular, assuming the steady running state of retarder as the working condition, flow and temperature fields have been obtained for the rotor. The influence of airflow path on heat dissipation has been analysed, and the influence of the temperature field distribution on the performance of retarder has been discussed accordingly. The results show that when the steady running state of the turntable is considered, the More >

Chang Su^1,2, Qiangqiang Zheng^3,*, Wukun Zhao⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 947-960, 2020, DOI:10.32604/fdmp.2020.09676 - 09 October 2020

Abstract In this research, the dynamics of wet spray nozzles with different geometries, used to accelerate shotcrete, are investigated on the basis of a suitable three-dimensional mathematical model and related numerical method. Simulations have been conducted in the frame of the SIMPLEC algorithm. The k-ε turbulence model has been used to account for turbulent effects. The study shows that when the angle of the convergent section is less than 3°, it has a scarce effect on the dynamics of the jet of shotcrete; with the increase of the convergence angle, the shotcrete jet velocity decreases and More >

Sheng Bai, Feng Bao^*, Fengzhi Zhao, Miaomiao Liu

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 935-946, 2020, DOI:10.32604/fdmp.2020.010113 - 09 October 2020

Abstract The main objective of the present study is the development of a new algorithm that can adapt to complex and changeable environments. An artificial fish swarm algorithm is developed which relies on a wireless sensor network (WSN) in a hydrodynamic background. The nodes of this algorithm are viscous fluids and artificial fish, while related ‘events’ are directly connected to the food available in the related virtual environment. The results show that the total processing time of the data by the source node is 6.661 ms, of which the processing time of crosstalk data is 3.789… More >