Rongge Xiao^a , Wenbo Jin^a,*, Shicong Han^b , Rui Li^a , Xuewen Cao^c

Frontiers in Heat and Mass Transfer, Vol.9, pp. 1-8, 2017, DOI:10.5098/hmt.9.6

Abstract Combines theories of gas dynamics, fluid dynamics and numerical heat transfer theory, the condensing flow characteristics of water vapor in wet natural gas within the Laval nozzle were studied. A mathematical model was developed to predict the spontaneous condensing phenomenon in the supersonic flows using the classical nucleation and droplet growth theories. The numerical approach is validated with the experimental data by using UDF and UDS modules in FLUENT software, which shows a good agreement between them, and showed that the mathematical model can better predict the parameter changes in the condensation process. The condensation characteristics of water vapor in… More >

Huan Zheng^a,*, Yuliang Ma^b , Huaping Mei^c , Xiaohong Xu^a , Xiguang Chen^d , Xunchen Cao^e

Frontiers in Heat and Mass Transfer, Vol.11, pp. 1-6, 2018, DOI:10.5098/hmt.11.34

Abstract The supersonic separator has proved to be an effective method to condense and separate CO₂ from natural gas, and the inlet temperature plays a vital role on condensation characteristics of CO₂ in the supersonic separator due to the instability temperature of wellhead natural gas. In this paper, the physical and mathematical models for the supersonic condensation process of CO₂ in the natural gas were established on the basis of CO₂ droplet surface tension, nucleation and growth model. The flow and condensation parameters were investigated under different temperature conditions. The results show that when the inlet gas pressure is 8.0 MPa,… More >

Rongge Xiao^a,*, Shuaishuai Jin^a, Xin Feng^b, Peng Zhang^c, Zheng Dai^c

Frontiers in Heat and Mass Transfer, Vol.16, pp. 1-7, 2021, DOI:10.5098/hmt.16.25

Abstract With the increasing production and use of natural gas, the supersonic nozzle has become focus of the impurity removal research. In this paper, the modified classical nucleation model is used as the condensation nucleation model, and the Gyarmathy growth model is selected as the droplet growth model. Based on the assumption of no phase slip and Eulerian two fluid model, the flow control equation of wet natural gas is established. By giving the selection criteria as a turbulence equation, the SRK real gas equation is used to carry out the corresponding numerical simulation. The required supersonic nozzle structure and grid… More >

Xiaohui Cheng¹, Haiqing Si^1,*, Yao Li¹, Peihong Zhang²

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.2, pp. 1729-1742, 2023, DOI:10.32604/cmes.2023.022694

Abstract To understand the influence of the initial release conditions on the separation characteristics of the store and improve it under high Mach number (Ma = 4) flight conditions, the overset grid method and the Realizable turbulence model coupled with an equation with six degrees of freedom are used to simulate the store released from the internal bay. The motion trajectory and the attitude angle of the store separation under the conditions of different centroid, velocity, height and control measures are given by the calculated result. Through analysis, the position of the centroid will affect the separation of the store, which needs to… More >

Javed S. Shaikh^1,*, Krishna Kumar¹, Khizar A. Pathan², Sher A. Khan³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1637-1653, 2023, DOI:10.32604/fdmp.2023.025113

Abstract The complex fluid-dynamic instabilities and shock waves occurring along the surface of a two-dimensional wedge at high values of the Mach number are studied here through numerical solution of the governing equations. Moreover, a regression model is implemented to determine the pressure distribution for various Mach numbers and angles of incidence. The Mach number spans the interval from 1.5 to 12. The wedge angles (θ) are from 5° to 25°. The pressure ratio (P₂/P₁) is reported at various locations (x/L) along the 2D wedge. The results of the numerical simulations are compared with the regression model showing good agreement. More >

Ridwan¹, Sher Afghan Khan^1,*, Jaffar Syed Mohamed Ali¹, Mohd. Azan Mohammed Sapardi¹, Abdul Aabid²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1655-1678, 2023, DOI:10.32604/fdmp.2023.025230

Abstract In the present study, the base pressure variations induced by the presence of a cavity, known to have a strong influence of the behaviour of supersonic projectiles, are investigated through numerical solution of the balance equations for mass, momentum, and energy. An area ratio of four is considered and numerical simulations are carried out at Mach M = 1.2, 1.4, 1.6, and 1.8 assuming no cavity or cavity locations 0.5D, 1D, 1.5D, and 2D. The inlet pressure of the nozzle is considered as a flow variable. The Taguchi method is also used, and the considered cases are then analyzed using… More >

Yong Zheng¹, Lei Zhao¹, Yujiang Wang¹, Feng Chang¹, Weijia Dong^2,*, Xinying Liu², Yunfei Li², Xiaohan Zhang², Ziyuan Zhao³

Energy Engineering, Vol.120, No.2, pp. 529-540, 2023, DOI:10.32604/ee.2023.022765

Abstract Supersonic separation technology is a new natural gas sweetening method for the treatment of natural gas with high CO₂ (carbon dioxide) content. The structures of the Laval nozzle and the supersonic separator were designed, and the mathematical models of supersonic condensation and swirling separation for CO₂-CH₄ mixture gas were established. The supersonic condensation characteristics of CO₂ in natural gas and the separation characteristics of condensed droplets under different inlet pressures were studied. The results show that higher inlet pressure results in a larger droplet radius and higher liquid phase mass fraction; additionally, the influence of centrifugal force is more pronounced,… More >

Nur Husnina Muhamad Zuraidi¹, Sher Afghan Khan^1,*, Abdul Aabid^2,*, Muneer Baig², Istiyaq Mudassir Shaiq³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.3, pp. 807-829, 2023, DOI:10.32604/fdmp.2023.023246

Abstract In this study, a duct is considered and special attention is paid to a passive method for the control of the base pressure relying on the use of a cavity with a variable aspect ratio. The Mach number considered is 1.8, and the area ratio of the duct is 2.56. In particular, two cavities are examined, their sizes being 3:3 and 6:3. The used L/D spans the interval 1–10 while the NPRs (nozzle pressure ratio) range from 2 to 9. The results show that the control becomes effective once the nozzles are correctly expanded or under-expanded. The pressure contours at… More >

Hao Tian, Yongkang Zheng^*, Hanxin Zhang

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.1, pp. 207-222, 2023, DOI:10.32604/fdmp.2023.019790

Abstract In this paper, some typical methods to promote mixing in supersonic combustion are reviewed, and the fluid-dynamic mechanism underpinning the development of the supersonic shear layer in the presence of a streamwise vortex is analyzed through computational fluid dynamics. It is proven that the streamwise vortex-couple method is an excellent approach to enhance mixing. A specific combustor design is proposed accordingly. More >

Wei Xia^1,2,*, Weilin Kong¹, Yupeng Feng¹, Shengping Shen^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.24, No.1, pp. 1-2, 2022, DOI:10.32604/icces.2022.08765

Abstract Post-buckling and panel flutter behaviors of ceramic-metal FGM plates are studied for the skins of supersonic aircrafts. The effects of asymmetric material and temperature distributions, as well as the aerodynamic loads, on the thermo-mechanical response of FGM plates are discussed using finite element simulations. The aero-thermo-elastic model is established by using the simple power law material distribution, the rule of mixture for material effective properties, the nonlinear Fourier equations of heat conduction, von-Karman strain-displacement nonlinear relations, and the piston theory for supersonic aerodynamics. The finite element equations are established using the first-order shear deformable plate elements. The thermal post-buckling equilibrium… More >