The classical theory of homogeneous bubble nucleation is reconsidered by employing a phenomenological barrier in the capillarity approximation that utilizes superheat threshold achieved experiments. Consequently, an algorithm constructed for evaluation temperatures boiling (tensile strengths cavitation), critical radii and steady-state rates. theorem written this framework applied to employed. calculated show excellent agreement over wide range liquid pressures most substances investigated....

A semiphenomenological droplet model, which corrects for the macroscopic surface tension and monomer–monomer interactions from real gas behavior (second virial coefficient) correlation between mean area of a cluster number molecules constituting over all ranges temperature below critical point, is proposed by modifying Fisher’s theory condensation. steady-state nucleation rate equation derived compared with expansion diffusion cloud chamber data variety substances. An overall good agreement...

Quasi-one-dimensional cavitating nozzle flows are considered by employing a homogeneous bubbly liquid flow model. The nonlinear dynamics of bubbles is described modified Rayleigh–Plesset equation that takes into account bubble/bubble interactions local mean-field theory and the various damping mechanisms coefficient, lumping them together in form viscous dissipation. resulting system quasi-one-dimensional equations then uncoupled leading to third-order ordinary differential for speed. This...

Quasi-one-dimensional steady-state cavitating nozzle flows with homogeneous bubble nucleation and nonlinear dynamics are considered using a continuum bubbly liquid flow model. The onset of cavitation is modeled an improved version the classical theory nucleation, bubbles described by Rayleigh-Plesset equation. Using polytropic law for partial gas pressure within accounting damping mechanisms, in crude manner, effective viscosity, stable solutions stationary shock waves as well unstable...

The validity of the reduced order [Delale and Pasinlioglu, “Acoustic cavitation model based on a novel gas pressure law,” AIP Adv. 11, 115309 (2021)] classical polytropic laws during response bubble to variations in surrounding liquid is investigated. In particular, from exact expression coupled thermal behavior bubbles, we identify conditions where law hold. We then distinguish three regimes for change state its nonlinear oscillations as nearly isothermal, transition, adiabatic regimes,...

The one-dimensional (1-D) asymptotic solution of subcritical transonic nozzle flows with nonequilibrium homogeneous condensation is presented. An algorithm based on a local iterative scheme that exhibits the in distinct zones developed for moist air expansions under atmospheric supply conditions. Two models characterize state condensed phase as water drops or ice crystals are employed, together classical nucleation theory and Hertz–Knudsen droplet growth law. It shown 1-D predictions good...

The propagation of a pressure wave in an initially quiescent bubbly liquid relatively high void fraction contained two-dimensional (2D) or three-dimensional (3D) rectangular domain is investigated by direct numerical simulations the Navier-Stokes equations using front-tracking/finite-volume method. gas inside bubbles either set equal to constant varied polytropic relation. Results obtained for 2D and 3D domains show mean shock speeds agreement with those one-dimensional homogeneous theory.

A detailed analysis of supercritical transonic nozzle flows with stationary normal shock waves is presented. classification scheme based on the location obtained using asymptotic methods, and four distinct flow regimes are distinguished. simple fitting technique that determines within any desired precision introduced. Consequently, an algorithm exhibits solution in each regime developed for expansion moist air nozzles atmospheric supply conditions by utilizing classical nucleation theory...

The compressible nozzle flow of a mixture condensible vapor and an inert carrier gas with nonequilibrium condensation is considered. An asymptotic method used respect to two disparate parameters appearing in the rate equation. A high activation limit another consideration that signify large nucleation time followed by small droplet growth are employed. Under limits, coupled integral equation so controlled function homogeneous over its six zones there appears be one-to-one correspondence...

A bubble fission model that takes into account energy dissipation during violent collapses of cavitation bubbles is introduced by assuming volume conservation and continuity the gas pressure instantaneous breakup, invoking either Rayleigh–Taylor instability or high speed microjet formation. In particular, a modified Rayleigh–Plesset equation derived for volumetric motion fragments in rebound. Results obtained under signal typical confirm scaling law Brennen [C. E. Brennen, “Fission...

The axially symmetric collapse and growth of a cylindrical bubble are considered. A universal law dynamics is obtained when the pressure at boundary that inside satisfy certain conditions. Both vapor bubbles having constant gas obeying isothermal Moreover, for bubbles, energy equation within considered in uniform approximation effect heat conduction through wall, an exact particular solution, leading to explicit temperature expressions, obtained. Finally, findings validated by direct...

Recent investigations of bubbly cavitating nozzle flows using the polytropic law for partial gas pressure have shown flow instabilities that lead to flashing solutions. Here, we investigate stabilizing effect thermal damping on these instabilities. For this reason consider energy equation within bubble, assumed be composed vapor and gas, in uniform approximation with low concentration. The is fixed by saturation corresponding interface temperature, which evaluated assuming thin boundary...

Journal Article On the temporal stability of steady-state quasi-1D bubbly cavitating nozzle flow solutions Get access Şenay Pasinlioğlu, Pasinlioğlu † Faculty Science and Letters, Department Mathematics, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey †Email: pasinliogl@itu.edu.tr Search for other works by this author on: Oxford Academic Google Scholar Can F. Delale, Delale Aeronautics Astronautics, TÜBİTAK Feza Gürsey Institute, PO Box 6, 81220 Çengelköy, Günter H. Schnerr...

Prandtl–Meyer flows with embedded oblique shock waves due to excessive heat release from condensation (supercritical flows) are considered by extending the subcritical asymptotic solution of Delale & Crighton (1998). The origin is located construction envelope family characteristics emanating either corner or deflected wall in parabolic approximation. A fitting technique for introduced small deflection angle approximation and law a streamline through an wave established within same...

The thermal behaviour of a spherical gas bubble in liquid driven by an acoustic pressure is investigated the uniform approximation employing iterative method to solve energy balance equations between and surrounding for temperature distribution inside bubble. It shown that first solution leads order law as polytropic power wall radius, with index given explicit function isentropic exponent gas. resulting reduces classical isothermal adiabatic laws appropriate limits. then applied...

A two-fold Cayley tree graph with fully q-coordinated sites is constructed and the ferromagnetic Ising model on solved exactly. It shown that a phase transition results in zero field at critical Bethe temperature spontaneous magnetization below temperature.

Prandtl–Meyer flows with heat addition from homogeneous condensation not exceeding a critical value (subcritical flows) are investigated by an asymptotic method in the double limit of large nucleation time followed small droplet growth time. The physically distinct zones, detailed analytical structure, displayed along streamlines and flow field each zone is determined utilizing solution rate equation streamlines. In particular wave front, which corresponds to states maximum streamlines,...

In this article the computational and asymptotic methods used in aeroacoustics are reviewed. particular, two different aeroacoustic applications demonstrated.In first problem we investigate second order predictions of thickness loading noise a subsonic B-bladed helicopter rotor far field compare SPL results with those full numerical computations. The formula seem to be better agreement computations than formula. problem, effect acoustic wave propagation transonic nozzle flow is investigated...