This paper presents a universal engineering model, which can be used to formulate both counterflow and crossflow cooling towers. By using fundamental laws of mass and energy balance, the effectiveness of heat exchange is approximated by a second order polynomial equation. Gauss-Newton and Levenberg-Marquardt methods are then used to determine the coefficients from manufactures data. Compared wi...

In this paper we investigate the role of convection in clusters of galaxies. A number of studies have shown that the convective stability criterion for the intracluster medium (ICM) is very different from the Schwarzchild criterion due to the effects of anisotropic thermal conduction and cosmic rays. Building on these studies, we present a model in which a central active galactic nucleus (AGN) ...

Luminescence refrigeration in semiconductors is studied using a model that includes the rate equations for carriers and photons as well as the influence of spectral dependent photon recycling. Expressions are derived for cooling efficiency, cooling power density, and the minimum external quantum efficiency required for cooling. These results show that net cooling is accessible and that photon r...

BACKGROUND AND OBJECTIVES Explanations for laparoscopic-induced hypothermia fail to explain clinical observations. It is possible that water evaporation occurs from the jet stream of gas inflation resulting in tissue surface super-cooling leading to tissue damage and drying. METHODS Theoretical calculations based on thermal conductivity, mass transfer effects and heat flux considerations corr...

Recent theoretical and experimental studies of evaporation have suggested that on average, molecules in the higher-energy tail of the Boltzmann distribution are more readily transferred into the vapor during evaporation. To test these conclusions, the evaporative cooling rates of a droplet train of liquid water injected into vacuum have been studied via Raman thermometry. The resulting cooling ...

Microscale freeze-drying makes rapid process cycles possible for early-stage formulation development. To investigate the effects of equipment scale and cooling rate on the solid state properties and the protein's secondary structure of a sample, three binary formulations of catalase were prepared and freeze-dried with sucrose, mannitol, or (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD). The protein...

We report on the solidification of Au49, Ag5.5, Pd2.3, Cu26.9, Si16.3 bulk metallic glass under various strain rates. Using a copper mold casting technique with a low strain rate during solidification, this alloy is capable of forming glassy rods of at least 5 mm in diameter. Surprisingly, when the liquid alloy is splat cooled at much higher cooling rates and large strain rates, the solidified ...