ISSN:
1066-8527
Keywords:
Chemistry
;
Chemical Engineering
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
When a gas under pressure is released, the momentum imparted to it causes the gas to mix with the surrounding air. A series of tests was carried out, and a model was used to determine the dynamics of the gas and air mixing for releases of a very short time duration. The amount of mixing that occurs when a pressurized fluid is released was determined by filling a container with varying mixtures of fumed silica and nitrogen, by bursting the container's rupture disks at fixed pressures, and by measuring the cloud velocity, location, and size at successive time intervals. A two-stage model was developed to predict the location, size, and fluid concentration (i.e., degree of dilution) of the cloud resulting from the release of a two-phase fluid composed of a non-flashing or non-evaporating dense phase. The dimensionless form of the model (ρ0u0t/ρ0r0) was found to correlate the cloud properties over initial pressures ranging from 3.1 to 70.7 barg (46 to 1025 psig), and gas quality ranging from 0.2 to 0.7 (gas mass fraction). Both the model and the data showed that the initial fluid concentration was reduced by factor of 300 to 1000 as a result of the momentum imparted mixing. This dilution is in addition to that resulting from atmospheric dispersion. Combining the predicted dilution effect from the instantaneous release with atmospheric dispersion to predict both near field and far-field concentration is an important application of this two stage model.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/prs.680130117
Permalink
