Characterising amorphous pharmaceuticals using PDF methods

Amorphous pharmaceuticals often suffer from poor physical stability, which can negate their high solubility, fast dissolution rate, and better oral bioavailability vs. crystalline forms. This represents a major hurdle to processing, storage, and delivery of amorphous pharmaceuticals. Several approaches to addressing these problems have been pursued, but there is still a need for a general method for stabilizing the amorphous form. We describe a novel approach using a water-unstable metal-organic framework as a drug delivery vehicle that demonstrates improved amorphous form stability accompanied by remarkably enhanced solubility and a fast dissolution rate. This research project spanned eleven years from conception to realization and dissemination. With origins in understanding the stability or porous solids for energy storage materials, the work also highlights potential of basic science understanding to illuminate new areas of application.

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Modeling of heat transfer and differential diffusion in transported PDF methods

Combustion and Flame ◽

10.1016/j.combustflame.2014.01.021 ◽

2014 ◽

Vol 161 (8) ◽

pp. 2107-2119 ◽

Cited By ~ 7

Author(s):

Andreas Fiolitakis ◽

Peter R. Ess ◽

Peter Gerlinger ◽

Manfred Aigner

Keyword(s):

Heat Transfer ◽

Differential Diffusion ◽

Pdf Methods

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Investigation of Temperature Statistics in Turbulent Rayleigh-Bénard Convection using PDF Methods

Journal of Physics Conference Series ◽

10.1088/1742-6596/318/8/082008 ◽

2011 ◽

Vol 318 (8) ◽

pp. 082008

Author(s):

J Lülff ◽

M Wilczek ◽

R Friedrich

Keyword(s):

Bénard Convection ◽

Benard Convection ◽

Pdf Methods ◽

Rayleigh Benard Convection ◽

Rayleigh Benard

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Towards the Use of Eulerian Field PDF Methods for Combustion Modeling in IC Engines

SAE International Journal of Engines ◽

10.4271/2014-01-1144 ◽

2014 ◽

Vol 7 (1) ◽

pp. 286-296 ◽

Cited By ~ 4

Author(s):

Tommaso Lucchini ◽

Gianluca D'Errico ◽

Francesco Contino ◽

Mehdi Jangi

Keyword(s):

Combustion Modeling ◽

Pdf Methods ◽

Ic Engines

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Modeling a Non-Premixed Industrial Gas Turbine Combustor by a Transported PDF Approach With ILDM Chemistry

Volume 2: Turbo Expo 2007 ◽

10.1115/gt2007-27370 ◽

2007 ◽

Author(s):

Sebastian Harder ◽

Franz Joos

Keyword(s):

Gas Turbine ◽

Particle System ◽

Measurement Techniques ◽

Combustion Process ◽

Generic Model ◽

Numerical Comparison ◽

Gas Turbine Combustor ◽

Turbulent Diffusion Flame ◽

Pdf Methods ◽

Industrial Gas Turbine

The combustion process in a typical can combustor of an industrial gas turbine is determined by the nature of turbulent flow, the chemical reaction and the interaction with each other. Turbulent non-premixed combustion can be divided into different flame regimes in terms of time- and length scales. A typical non-premixed turbulent diffusion flame in a gas turbine combustor covers all regimes. PDF methods are suitable to describe the entire combustion regime without any limitation to a certain regime. In this paper a hybrid pdf/RANS method is presented. The pdf model is based on the transported composition pdf equation, coupled with a commercial three dimensional CFD solver. A stochastic particle system in a Lagrangian framework is used to solve the pdf equation. The chemistry is described by an ILDM approach. The numerical results have been validated with measurements. The test rig consists of an non-premixed gas turbine can combustor with a typical primary and secondary zone. A main air swirler stabilizes the natural gas/air mixture in the primary zone, followed by a burnout and a mixing zone. The setup is investigated using conventional measurement techniques. Field measurements of compositions and mixture fraction as well as temperature are compared with the pdf/RANS calculations. The benefit of this approach is a realistic prediction of all relevant species. The complete one point statistics of the numerical calculations are used to identify the different combustion regimes from the combustor to the exit. The numerical comparison of pdf-, edm- and flamelet-model shows that the pdf approach can be used to describe a realistic gas turbine combustor. In the past, pdf-methods were applied only on simple generic model flames. The purpose of the presented paper is to demonstrate the application of a transported-pdf approach to a realistic gas turbine combustor.

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