|
|
Klasická nukleační teorie-Poznámky k parním turbinám
Němec, T. ; Maršík, František
The Classical Nucleation Theory (CNT) is modified to treat a special case of admixtures - electrolytes. Thermodynamic features of aqueous electrolytic solutions are described in a slightly different way from that for ordinary liquid mixtures. Namely, the excess Gibbs energy is expressed in terms of the osmotic coefficient and the mean stochiometric activity coefficient instead of the activity coefficients.
|
|
|
Rozložení energie v kavitační bublině během jejího růstu a kolapsu
Müller, M. ; Maršík, František ; Garen, W.
Shock wave generation during the bubble growth and collapse and the corresponding energy separation were investigated experimentally. The calculation of the shock wave energy was based on the experimentally determined shock wave velocity profile. The possibility of using the similarity solution to determine the shock wave intensity is discussed. The velocity field around the collapsing bubble was visualized and compared with the numerical simulation using the commercial FLUENT code.
|
|
|
Some possibilities of analytical description of strong non-adiabatic gas compression
Bayer, Zdeněk
Paper deals with modelling of the gas state- and thermodynamic behaviour in cavitation bubbles. After recent presentation of model M3 based on the more realistic idea of the heat transfer in the course of bubble compression, introduces its advanced version M4. The comparison of the polytropic and M4 model of process shows the results for high volume compression ratios may differ in tenths of percent. In a like range lies the discrepancy caused by using more accurate state equation and temperature dependence of the heat capacity.
|
|
|
Description of state behavior along the critical isotherm and along the saturation curve using simple equations of state. Part II
Bayer, Zdeněk
The contribution deals with a group of 13 equations of state (EOS), predominantly of the van der Waals type, both classical and also newly developed in the IT AS ČR. In the region from the triple- to the critical points, the changes in the temperature functions (1st criterion), deviations of the derivate from the correct value, (2nd criterion), and the course of the liquid spinodal are investigated. Ordinary water substance is used as the model medium. The data and/or equations following from the critical point and saturation curve conditions are given. The calculations showed that considerable improvements may be arrived at separately applied criteria but at their simultaneous application the improvement has been not gained.
|
|
|
Description of state behavior along the critical isotherm and along the saturation curve using simple equations of state ů part I
Bayer, Zdeněk
The contribution deals with a group of 13 equations of state (EOS), predominantly of the van der Waals type, both classical and also newly developed in the Institute. In the region from the triple- to the critical points, the changes in the temperature functions (1st criterion), deviations of the derivate (2nd criterion), and the course of the liquid spinodal are investigated. Ordinary water substance is used as the model medium. The possibilities of improving EOS of this type are searched. While at separately applied criteria some improvements were arrived at, the simultaneous application of criteria gave no satisfactory results.
|
|
| |
|
| |
|
| |
|
| |
|
| |
guest ::
