Визуализация потока воздуха в вихревой трубе с использованием различных моделей турбулентности

Visualization of air flow in Ranque-Hilsch vortex tube performed by numerical simulations with standard k-ε and SAS-SST turbulence models is presented in the paper. SAS-SST turbulence model predicted the existence of secondary largescale vortex structures within the computational domain instead k-ε model showed axisymmetrical flow. Existence of large-scale secondary vortex structures is in agreement with experimental data.В статье представлены результаты визуализации потока воздуха в вихревой трубе Ранка-Хилша, выполненной с помощью численного моделирования. Были использованы k-ε и SAS-SST модели турбулентности. SAS-SST модель турбулентности показала наличие вторичных крупномасштабных вихревых структур в расчетном домене, в отличие от k-ε модели. Факт наличия крупномасштабных вторичных вихревых структур хорошо согласуется с экспериментальными данными

Search for a signal on intermediate baryon systems formation in hadron-nuclear and nuclear-nuclear interactions at high energies

We have analyzed the behavior of different characteristics of hadron-nuclear and nuclear-nuclear interactions as a function of centrality to get a signal on the formation of intermediate baryon systems. We observed that the data demonstrate the regime change and saturation. The angular distributions of slow particles exhibit some structure in the above mentioned reactions at low energy. We believe that the structure could be connected with the formation and decay of the percolation cluster. With increasing the mass of colliding nuclei, the structure starts to become weak and almost disappears ultimately. This shows that the number of secondary internuclear interactions increases with increasing the mass of the colliding nuclei. The latter could be a reason of the disintegration of any intermediate formations as well as clusters, which decrease their influence on the angular distribution of the emitted particles.Comment: 2 pages and one figur

Single - particle correlations in events with the total disintegration of nuclei

New experimental data on the behaviour of the single-particle two-dimensional correlation functions R versus Q (Q is the number of nucleons emitted from nuc- lei) and Ap (Ap is the mass of projectile nuclei) are presented in this paper. The interactions of protons, d, 4He and 12C nuclei with carbon nuclei (at a momentum of 4.2 A GeV/c) are considered.The values of R are obtained separately for pi minus mesons and protons.In so doing,the values of R are normalized so that -1=<R=<1.The value of R=0 corresponds to the case of the absence of corre- lations.It has been found that the Q- and Ap-dependence of R takes place only for weak correlations (R< 0.3).In the main (90 %),these correlations are con- nected with the variable pt and have a nonlinear character, that is the regi- ons with different characters of the Q-dependence of R are separated: there is a change of regimes in the Q-dependences of R.The correlations weaken with increasing Ap, and the variable R gets the least values of all the considered ones in 12CC interactions.Simultaneously with weakening the correlations in the region of large Q, the character of the Q-dependence of R changes.Comment: 17 pages, submitted to Phys. Rew.

Deceleration of the Cold Flow in the Vortex Tube

none5siEnhancement of the cold flow deceleration unit is considered in the paper to improve the energetic efficiency of the vortex tube. It was shown that the gradual expansion of the cross-section in the cold flow diffuser is inefficient for reducing the gas flow velocity in presence of its significant rotation. Installation of a blade grid at the entrance to the cold flow diffuser was suggested for interruption of the flow swirling. A notable reduction of the energy losses has been demonstrated improving the efficiency of the vortex tube.openAnoshin N.; Khait A.; Bianco V.; Noskov A.; Alekhin V.Anoshin, N.; Khait, A.; Bianco, V.; Noskov, A.; Alekhin, V