Topic
Mass transfer coefficient
About: Mass transfer coefficient is a research topic. Over the lifetime, 7827 publications have been published within this topic receiving 168354 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper, the reduction and subsequent sulfidation of single cylindrical pellets of ZnFe2O4 have been studied in a microbalance reactor and the time-conversion results during sulfidation are consistent with the unreacted core model assuming the global kinetics are controlled by mass transfer and pore diffusion.
89 citations
TL;DR: In this article, a numerical study of the dynamic performance of an ad-hoc cooling system for automobile waste heat recovery is presented, where a new lumped parameter non-equilibrium model is developed and used to investigate and optimize the waste heat cooling system, which is estimated to operate in quicker cycles when compared with the time needed to reach equilibrium.
89 citations
TL;DR: In this paper, heat and mass transfer modeling in the air drying of solids is considered as a two-stage procedure, in which the first stage aims to discover the dominant heat versus mass, internal versus external, and the latter aims to formulate empirical equations for the calculation of the corresponding heat andmass transport properties (mass diffusivity, thermal conductivity, boundary heat and transfer coefficients).
89 citations
TL;DR: Oxygen transfer enhancements from fiber‐optic dissolved oxygen sensing technique were directly translatable into enhancements in overall fermenter productivity for actual microbial cultivation systems.
Abstract: A new fiber-optic dissolved oxygen sensing technique was applied to the study of two-phase aqueous/perfluorocarbon (pfc) dispersions. These dispersions were examined for their oxygen transfer enhancement capability in the absence and presence of an oxygen-consuming reaction. For the pfc-in-water dispersions, oxygen uptake rate (OUR) enhancements were equal both with and without oxygen-consuming cells present in the aqueous phase. In contrast, for water-in-pfc dispersions, OUR enhancements inthe presence of reaction were limited by oxygen diffusion across the aqueous phase droplets. Nevertheless, enhancement factors of 5-10 on an aqueous phase volume basis were obtained in a 75% pfc dispersion.These oxygen transfer enhancements were directly translatable into enhancements in overall fermenter productivity for actual microbial cultivation systems.
89 citations
TL;DR: The concept of the active surface was introduced in this article, which is the surface on which transfer of momentum, energy, and mass from the gas to the particle takes place, i.e., the area on which the transfer of mass, momentum, and energy from a gas to a nanoparticle takes place.
Abstract: The dynamics of nanoparticles in a carrier gas are governed by the physical and chemical nature of the surface. The total surface area can be divided into an “active” and a “passive” part. The active surface is the surface on which transfer of momentum, energy, and mass from the gas to the particle takes place. The experiments show that the active surface may be determined in physically very different in situ experiments such as measuring the mobility b, the diffusion constant D, or the mass transfer coefficient K of the particle. The concept of the active surface manifests itself in scaling laws Kb=const, KD=const, and Yb=const, found valid over a large range of particle shapes and sizes. Y is the yield of low energy photoelectrons from the particles upon irradiating the carrier gas with light of energy below the ionization energy of the carrier gas molecules but above the photoelectric threshold of the particles. While K, D and b are independent of the chemical nature of the particles as far as we know ...
89 citations