A linear electric motor to study turbulent hydrodynamics

Dimonte, Guy; Morrison, J.J.; Hulsey, Scott; Nelson, Don H.; Weaver, Sam; Susoeff, A.R.; Hawke, R.S.; Schneider, M. B.; Batteaux, Jan; Lee, Dean; Ticehurst, Judy

doi:10.1063/1.1146585

Cited by 20 publications

(8 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Later, Dimonte & Schneider (2000) found bubbles and spike responses of θ b = 0.25 and θ s = 0.3 (for A ∼ 0.7). However, to compensate for demixing caused by any residual deceleration in their linear electric motor system (Dimonte et al 1996), it was suggested that these exponents may have to be increased by ∼10 %. Experiments performed using membranes by Prasad et al (2000) produced a late-time growth exponent of (0.26 ≤ θ ≤ 0.33).…”

Section: Mixing Widths and Scalingmentioning

confidence: 99%

The effect of initial conditions on mixing transition of the Richtmyer–Meshkov instability

et al. 2020

View full text Add to dashboard Cite

show abstract

Section: Mixing Widths and Scalingmentioning

confidence: 99%

The effect of initial conditions on mixing transition of the Richtmyer–Meshkov instability

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Here, we conduct experiments on the Linear Electric Motor (LEM) [13] using different acceleration profiles to measure the critical wavelength l c and amplitude P cr , and to compare 2D and 3D perturbations. The elastic material is chosen to be yogurt because its constitutive properties ͑m, h, s 0 ͒ are well characterized [14] and satisfy Eqs.…”

mentioning

confidence: 99%

Rayleigh-Taylor Instability in Elastic-Plastic Materials

1998

Self Cite

View full text Add to dashboard Cite

The Rayleigh-Taylor instability is investigated in a material with a shear modulus m and yield stress s 0 . Incompressible experiments are conducted with constant and impulsive acceleration histories g͑t͒ using a fully characterized material. Two dimensional (2D) perturbations are found to be stabilized for wave number k . rg͞2m and initial amplitude h 0 , s 0 ͞rg, where r is the density. The stability region is larger for 3D perturbations. Unstable modes are found to grow classically during the acceleration phase, but they can recover elastically while coasting. [S0031-9007 (97)05230-7] PACS numbers: 47.20.Bp, 47.50. + dWhen an elastic-plastic plate is accelerated by a lower density fluid, the interface between them is Rayleigh-Taylor (RT) unstable [1-7], but the mechanical strength of the plate mitigates the growth. This occurs when metal plates are accelerated by high explosives (HE) [6,[8][9][10] or electrical currents [11], and in volcanic island formation due to the strength of the earth's crust [12].The effect of a shear modulus m and a tensile yield s 0 on RT stability is reviewed nicely by Robinson and Swegle (RS) [3]. The elastic force ϳ22mk 2 h can overcome the RT buoyancy ϳrgkh and stabilize small amplitude ͑kh ø 1͒ perturbations with wave numbers k . rg͞2m ϵ k c , (1) where r is the plate density and g is the acceleration. These modes may again be destabilized if the pressure drop across the initial amplitude h 0 exceeds the yield stress and drives the plastic flow, i.e., P ‫ء‬ ϵ rgh 0 ͞2s 0 $ P cr .(2) Estimates of the critical scaled pressure P cr for two dimensional (2D) perturbations are ϳ1.15͑͞1 1 e 2kH ͒ by Miles [1], where H is the plate thickness, ϳ1 by Drucker [2], ϳ0.58͓b 1 ͑b 2 1 1͒ 1͞2 ͔ 1͞2 by RS [3], where b ϵ 1 2 e 22kH , and ϳ͑1 2 0.86e 2kH͞ p 3 ͒ ͓͑1 2 e 2kH͞ p 3 ͒ 2 2 ͑k c ͞k͒ 2 ͔ by Nizovtsev and Raevskii (NR) [5,6]. The stability may be enhanced in 3D [2] with P cr ϳ 2 and reduced growth rates [6].Experiments [6,[8][9][10] in which metal plates are accelerated by HE find a P cr , 1 that decreases with l ϵ 2p͞k and show slower growth in 3D than in 2D [5]. Unfortunately, the uncertainties are large, ϳ50%, because the parameter variations are coarse and the material properties are uncertain at the high pressure. For example, to explain the observations, it is necessary to increase the static yield tenfold for weak aluminum (1100-0) but not for strong aluminum (6061-T6) and steel. If there is a strain rate dependence, as with viscosity ͑h͒, a reduced RT growth rate [3] may appear as strength since the experiments are short t ϳ 2͞ p kg. Also, Eq. (1) could not be tested because l c 2p͞k c exceeded the plate width.Numerical simulations [4,6] can treat the nonlinear constitutive properties and complex g͑t͒ profiles. For 10 GPa drive pressures, the simulations obtain P cr ϳ 0.4 at l 2H consistent with the HE experiments. However, the critical wavelength is observed to be much smaller than 4pm͞rg for the experimental conditions, possibly because k c H ø 1. At higher pressures, the values o...

show abstract

“…Once the flow becomes self‐similar, the growth of the instability is described by the power law and the corresponding coefficient θ . Numerical and experimental investigations suggested slightly different values for θ . The discrepancies in the estimation between the experiments and the numerical simulations are mainly due to the different perturbation wavelengths .…”

Section: Sources Of Uncertaintymentioning

confidence: 77%

“…Numerical and experimental investigations suggested slightly different values for . 33,35,35,67,[69][70][71] The discrepancies in the estimation between the experiments and the numerical simulations are mainly due to the different perturbation wavelengths. 72 Furthermore, the power law coefficient is correlated with the density ratio of the 2 fluids.…”

Section: Sources Of Uncertaintymentioning

confidence: 98%

Multidimensional quantification of uncertainty and application to a turbulent mixing model

Barmparousis

Drikakis

2017

Numerical Methods in Fluids

View full text Add to dashboard Cite

SUMMARYThis paper concerns the implementation of the generalized Polynomial Chaos (gPC) approach for parametric studies, including the quantification of uncertainty (UQ), of turbulence modelling. The method is applied to Richtmyer-Meshkov turbulent mixing. The K − L turbulence model has been chosen as a prototypical example and parametric studies have been performed to examine the effects of closure coefficients and initial conditions on the flow results. It is shown that the proposed method can be used to obtain a relation between the uncertain inputs and the monitored flow quantities, thus efficiently performing parametric studies. It allows the simultaneous calibration and quantification of uncertainty in an efficient numerical framework.

show abstract

A linear electric motor to study turbulent hydrodynamics

Cited by 20 publications

References 9 publications

The effect of initial conditions on mixing transition of the Richtmyer–Meshkov instability

The effect of initial conditions on mixing transition of the Richtmyer–Meshkov instability

Rayleigh-Taylor Instability in Elastic-Plastic Materials

Multidimensional quantification of uncertainty and application to a turbulent mixing model

Contact Info

Product

Resources

About