Abstract. Turbulent mixing of dry air affects the evolution cloud droplet size spectrum via various mechanisms. In a turbulent cloud, high- and low-vorticity regions coexist, inertial clustering droplets can occur in regions. The nonuniformity spatial distribution number droplets, variable vertical velocity vortical structures, dilution by entrainment/mixing may result supersaturation variabili...

This paper describes simple modifications to thermally diffusive laminar flow ultrafine condensation particle counters (UCPCs) that allow detection of ∼1 nm condensation nuclei with much higher efficiencies than have been previously reported. These nondestructive modifications were applied to a commercial butanolbased UCPC (TSI 3025A) and to a diethylene glycol-based UCPC (UMN DEG-UCPC). Size a...

Astrophysical multi-phase media display rich spatial structures, as for example the cold cirrus clouds found in the neutral atomic interstellar medium. Condensation of cold structures in locally compressed regions of turbulent thermally bistable flows is a plausible, not exclusive, origin for the structuration of the medium. Simulations in plane-parallel geometry show that trans-sonic convergen...

Experimental measurements of local heat tra nsfer coefficients and pressure drop are made for forced conv ection boiling and condensation for R134a-oil mixtures inside a horizontal tube. The results are compared with the experime ntal data of pure Rl34a. Average convection boiling and cond ensation heat transfer coefficients decreased about 20% at a 10\ o il mass fraction, and boiling and conde...

The growth by condensation of small water droplets in a three-dimensional homogeneous isotropic turbulent flow is considered. Within a simple model of advection and condensation, the dynamics and growth of millions of droplets are integrated. A droplet-size spectra broadening is obtained and it is shown to increase with the Reynolds number of turbulence, by means of two series of direct numeric...