A Caltech Library Service

A computationally efficient inorganic atmospheric aerosol phase equilibrium model (UHAERO)

Amundson, N. R. and Caboussat, A. and He, J. W. and Martynenko, A. V. and Savarin, V. B. and Seinfeld, J. H. and Yoo, K. Y. (2005) A computationally efficient inorganic atmospheric aerosol phase equilibrium model (UHAERO). Atmospheric Chemistry and Physics Discussions, 5 (5). pp. 9291-9324. ISSN 1680-7367.

PDF - Published Version
Creative Commons Attribution.


Use this Persistent URL to link to this item:


A variety of thermodynamic models have been developed to predict inorganic gas-aerosol equilibrium. To achieve computational efficiency a number of the models rely on a priori specification of the phases present in certain relative humidity regimes. Presented here is a new computational model, named UHAERO, that is both efficient and rigorously computes phase behavior without any a priori specification. The computational implementation is based on minimization of the Gibbs free energy using a primal-dual method, coupled to a Newton iteration. The mathematical details of the solution are given elsewhere. The model also computes deliquescence and crystallization behavior without any a priori specification of the relative humidities of deliquescence or crystallization. Detailed phase diagrams of the sulfate/nitrate/ammonium/water system are presented as a function of relative humidity at 298.15 K over the complete space of composition.

Item Type:Article
Related URLs:
URLURL TypeDescription
Seinfeld, J. H.0000-0003-1344-4068
Additional Information:© 2005 Author(s). This work is licensed under a Creative Commons Attribution, NonCommercial and ShareAlike Licence. Received: 17 August 2005 – Accepted: 13 September 2005 – Published: 28 September 2005 This work was supported by US Environmental Protection Agency grant X-83234201. The authors thank S. L. Clegg for providing the code for the PSC model based activity coefficient calculation.
Funding AgencyGrant Number
Environmental Protection Agency (EPA)X-83234201
Issue or Number:5
Record Number:CaltechAUTHORS:AMUacpd05
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:1951
Deposited By: Archive Administrator
Deposited On:25 Feb 2006
Last Modified:02 Oct 2019 22:48

Repository Staff Only: item control page