English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Effects of two types of shock topology, namely, small-scale shocklet andlarge-scale shock wave, on the statistics of temperature in compressibleturbulence were investigated by simulations. The shocklet and shock wave arecaused by the solenoidal and compressive modes of driven forces, respectively.Hereafter, the related two flows are called as SFT and CFT, respectively. Itshows that in SFT the temperature spectrum follows the k^-5/3 power law, andthe temperature field has "ramp-cliff" structures. By contrast, in CFT thetemperature spectrum obeys the k^-2 power law, and the temperature field isdominated by large-scale rarefaction and compression. The power-law exponentsfor the p.d.f. of large negative dilatation are -2.5 in SFT and -3.5 in CFT,close to theoretical values. For the isentropic assumption of thermodynamicvariables, the derivation in SFT grows with the turbulent Mach number (Mt), andfor same Mt, the variables in CFT are more anisentropic. The angle statisticsshows that the temperature gradient in CFT is preferentially perpendicular tothe anisotropic strain rate tensor. It tends to be parallel with the firsteigenvector and be orthogonal with the other two eigenvectors. For the cascadeof temperature, the temperature variance is increased by the viscousdissipation and the pressure-dilatation, but is decreased by the SGStemperature flux. The statistics of pressure-dilatation proves that thenegligible contribution of pressure-dilatation at small scales is due to thecancelations of high values between rarefaction and compression regions. Thestrongly positive skewness of the p.d.f.s of pressure-dilatation implies thatthe conversion from kinetic to internal energy through compression is moreintense than the opposite process through rarefaction. Furthermore, in SFT thefluctuations of pressure-dilatation approximately follow the Zeman model.

Effects of shock topology on temperature field in compressible turbulence