Direct numerical simulation of thermal channel flow for and

Alcántara-Ávila, Francisco; Hoyas, Sergio; Pérez-Quiles, M.J.

doi:10.1017/jfm.2021.231

Cited by 39 publications

(59 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(2004) reported , whereas more data at higher Reynolds number suggest (Alcántara-Ávila et al. 2021). Studies carried out with CMT typically tend to yield slightly higher values, namely (Pirozzoli et al.…”

Section: Resultsmentioning

confidence: 95%

“…Although the total heat flux resulting from the CMT approach is not strictly constant in time, it oscillates around its mean value under statistically steady conditions. Differences of the results obtained with the CMT and CHF approaches have been described by Abe & Antonia (2017) and Alcántara-Ávila et al (2021), which although generally small deserve some attention.…”

Section: Numerical Datasetmentioning

confidence: 97%

“…This is in contrast to properties related to the velocity field, which are significantly affected from use of a short domain . The interesting consequence of this observation is the possibility to carry out DNS of scalar fields in more limited domains, as also noted by Alcántara-Ávila et al (2021). In order to quantify uncertainties associated with numerical discretisation, additional simulations have been carried out by doubling the number of grid points in the azimuthal, radial and axial directions, respectively.…”

Section: Numerical Datasetmentioning

confidence: 99%

See 2 more Smart Citations

DNS of passive scalars in turbulent pipe flow

et al. 2022

View full text Add to dashboard Cite

We study the statistics of passive scalars at $Pr=1$ , for turbulent flow within a smooth straight pipe of circular cross section up to $Re_{\tau } \approx 6000$ using direct numerical simulation (DNS) of the Navier–Stokes equations. While featuring a general organisation similar to the axial velocity field, passive scalar fields show additional energy at small wavenumbers, resulting in a higher degree of mixing and in a $k^{-4/3}$ spectral inertial range. The DNS results highlight logarithmic growth of the inner-scaled bulk and mean centreline scalar values with the friction Reynolds number, implying an estimated scalar von Kármán constant $k_{\theta } \approx 0.459$ , which also nicely fits the mean scalar profiles. The DNS data are used to synthesise a modified form of the classical predictive formula of Kader & Yaglom (Intl J. Heat Mass Transfer, vol. 15 (12), 1972, pp. 2329–2351), which points to some shortcomings of the original formulation. Universality of the mean core scalar profile in defect form is recovered, with very nearly parabolic shape. Logarithmic growth of the buffer-layer peak of the scalar variance is found in the Reynolds number range under scrutiny, which well conforms with Townsend's attached-eddy hypothesis, whose validity is also supported by the spectral maps. The behaviour of the turbulent Prandtl number shows good universality in the outer wall layer, with values $Pr_t \approx 0.84$ , as also found in previous studies, but closer to unity near the wall, where existing correlations do not reproduce the observed trends.

show abstract

Section: Resultsmentioning

confidence: 95%

Section: Numerical Datasetmentioning

confidence: 97%

Section: Numerical Datasetmentioning

confidence: 99%

See 1 more Smart Citation

DNS of passive scalars in turbulent pipe flow

et al. 2022

View full text Add to dashboard Cite

show abstract

“…CFD, instead, relates a linear combination of the second derivatives with the values of the function. To explain the practical use of CFD schemes, we are going to work with one specific example, the scheme used in [29]. In that work, the authors used a stencil of seven points in the function and five in the second derivative.…”

Section: Cfd Techniquesmentioning

confidence: 99%

“…Later, in [27], the large structures of Couette flow were analyzed. In [28,29], the authors were able to increase the study for Pr > 0.7, reaching Pr = 10, and Re τ = 5000 for Pr = 0.7. Finally, this code has been used to study the large structures found in stratification problems, cite [30].…”

Section: Introductionmentioning

confidence: 99%

A Code for Simulating Heat Transfer in Turbulent Channel Flow

et al. 2021

Self Cite

View full text Add to dashboard Cite

One numerical method was designed to solve the time-dependent, three-dimensional, incompressible Navier–Stokes equations in turbulent thermal channel flows. Its originality lies in the use of several well-known methods to discretize the problem and its parallel nature. Vorticy-Laplacian of velocity formulation has been used, so pressure has been removed from the system. Heat is modeled as a passive scalar. Any other quantity modeled as passive scalar can be very easily studied, including several of them at the same time. These methods have been successfully used for extensive direct numerical simulations of passive thermal flow for several boundary conditions.

show abstract