Numerical modeling of a high-enthalpy shock tunnel driven by gaseous detonation

Luo, Kai; Wang, Qiu; Li, Jiwei; Li, Jinping; Zhao, Wei

doi:10.1016/j.ast.2020.105958

Cited by 7 publications

(3 citation statements)

References 24 publications

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“…However, due to the excessive power of high-enthalpy shock tunnels [5], it is very difficult to develop continuously-running shock tunnels. At the same time, the effective test duration is far less than the theoretical value due to the interaction of tunnel waves, viscous boundary layer interference [6,7], diaphragm rupture, the nozzle starting process, and other factors [8,9]. Furthermore, with the increase of the total enthalpy of the gas, the test duration decreases further [10].…”

Section: Introductionmentioning

confidence: 93%

Numerical and Experimental Study on the Duration of Nozzle Starting of the Reflected High-Enthalpy Shock Tunnel

Wang

et al. 2022

Applied Sciences

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The starting process of the flow in the nozzle of the JF-14 shock tunnel (1.6 m in length, 500 mm in outlet diameter) in the State Key Laboratory of High Temperature Gas Dynamics is analyzed by calculation and experiment. Two key factors which directly affect the duration of the nozzle starting are the velocity of the expansion wave and the low-velocity zone generated by the interaction between the secondary shock wave and boundary layer on the wall surface. In the process of the nozzle starting, the flow field stabilizes at the center of the nozzle outlet first, and then gradually stabilizes along the radius direction, thus defining the central startup and complete startup of the nozzle. It is found that there is a critical initial pressure. When the initial pressure is lower than the critical pressure, the airflow can reach stability in the nozzle outlet center with the shortest time, otherwise, the time required is much longer. The time required for the airflow to stabilize in the whole outlet section is mainly affected by the size of the low-velocity zone. It is also found that only at a very low initial pressure can the airflow simultaneously reach stability at the entire outlet of the nozzle.

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Section: Introductionmentioning

confidence: 93%

Numerical and Experimental Study on the Duration of Nozzle Starting of the Reflected High-Enthalpy Shock Tunnel

Wang

et al. 2022

Applied Sciences

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“…In Eq 26 , the area change and mixture viscosity are considered. For the determination of shear stress τ 0 , the Darcy-Weisbach friction factor f [ 15 , 40 , 41 ] for the pipe flow has been widely used for Q1D calculations [ 13 , 15 ], and can be represented as follows: …”

Section: Thermochemical Nonequilibrium Modelmentioning

confidence: 99%

“…Numerical simulations are therefore commonly performed to understand and diagnose the thermochemical nonequilibrium state inside the shock-tunnel facility and the hypersonic free-stream conditions at the nozzle exit. In numerical simulations, the three-dimensional flow calculations have an advantage of the performance analysis of the shock-tunnel facility [ 13 ]. However, the computational costs of the three-dimensional calculations are enormous to analyze the thermochemical nonequilibrium phenomena of the shock-tunnel flows.…”

Section: Introductionmentioning

confidence: 99%

Thermochemical nonequilibrium flow analysis in low enthalpy shock-tunnel facility

et al. 2020

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A thermochemical nonequilibrium analysis was performed under the low enthalpy shocktunnel flows. A quasi-one-dimensional flow calculation was employed by dividing the flow calculations into two parts, for the shock-tube and the Mach 6 nozzle. To describe the thermochemical nonequilibrium of the low enthalpy shock-tunnel flows, a three-temperature model is proposed. The three-temperature model treats the vibrational nonequilibrium of O 2 and NO separately from the single nonequilibrium energy mode of the previous two-temperature model. In the three-temperature model, electron-electronic energies and vibrational energy of N 2 are grouped as one energy mode, and vibrational energies of O 2 , O 2 + , and NO are grouped as another energy mode. The results for the shock-tunnel flows calculated using the three-temperature model were then compared with existing experimental data and the results obtained from one-and two-temperature models, for various operating conditions of the K1 shock-tunnel facility. The results of the thermochemical nonequilibrium analysis of the low enthalpy shock-tunnel flows suggest that the nonequilibrium characteristics of N 2 and O 2 need to be treated separately. The vibrational relaxation of O 2 is much faster than that of N 2 in low enthalpy condition, and the dissociation rate of O 2 is manly influenced by the species vibrational temperature of O 2. The proposed three-temperature model is able to describe the thermochemical nonequilibrium characteristics of N 2 and O 2 behind the incident and reflected shock waves, and the rapid vibrational freezing of N 2 in nozzle expanding flows.

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