Experiences with the open source model for disseminating information in computational gas-solids flow

National Energy Technology Laboratory (NETL) has been developing advanced gassolids flow models and promoting their use in the design of multiphase flow reactors encountered in fossil energy processes for over two decades. In addition to the successful use of the models to help with the design of fossil energy systems such as gasifiers, this research resulted in a general purpose gas-solids computational fluid dynamics code called MFIX. In 2001, MFIX was made open source (http://www.mfix.org). Since then over 750 researchers from 250 research institutions world-wide have downloaded the code, of which a recent survey has shown that at least 10% have become regular users of the code. Nearly 50 % of the respondents, who have been using the code for several years, indicated significant success in their research with MFIX. Over 40% of these users are graduate students, and the code has been used to complete several masters and Ph.D. theses. The enhancements to the code resulting from the academic research have migrated into the main code repository, the quality of which is ensured with extensive testing conducted periodically. The “open source model” provides a new method for code verification as many eyes are able to examine the source code. The use of MFIX has gone beyond its originally intended applications, primarily fluidization, to others, such as volcanology. This makes extensive model validation possible as different users exercise different configurations of the model for their applications. The “open source model” appears to be a particularly effective approach in the emerging field of computational gas-solids flow, where the theory and numerical techniques are rapidly evolving. In addition to the code, the MFIX website hosts several mailing lists that foster technical discussions among the users; an open citation index for literature on gas-solids flows is also maintained. Thus the open source code acts as a vehicle for collecting, verifying and disseminating information, and facilitating collaboration among users. The tools used for the collaboration, examples of successful transfer of information, and experiences with the “open source model” of information transfer and code verification are discussed in this paper.