0d2fd78864
Lagrangian injections now have a 'uniformParcelSize' control, which specifies what size of the parcels is kept uniform during a given time step. This control can be set to 'nParticles', 'surfaceArea' or 'volume'. The particle sizes, by contrast, are specified by the size distribution. For example, if 'uniformParcelSize nParticles;' is specified then all parcels introduced at a given time will have the same number of particles. Every particle in a parcel has the same properties, including diameter. So, in this configuration, the larger diameter parcels contain a much larger fraction of the total particulate volume than the smaller diameter ones. This may be undesirable as the effect of a parcel on the simulation might be more in proportion with its volume than with the number of particles it represents. It might be preferable to create a greater proportion of large diameter parcels so that their more significant effect is represented by a finer Lagrangian discretisation. This can be achieved by setting 'uniformParcelSize volume;'. A setting of 'uniformParcelSize surfaceArea;' might be appropriate if the limiting effect of a Lagrangian element scales with its surface area; interfacial evaporation, for example. Previously, this control was provided by 'parcelBasisType'. However, this control also effectively specified the size exponent of the supplied distribution. This interdependence was not documented and was problematic in that it coupled physical and numerical controls. 'parcelBasisType' has been removed, and the size exponent of the distribution is now specified independently of the new 'uniformParcelSize' control along with the rest of the distribution coefficients or data. See the previous commit for details. It is still possible to specify a fixed number of particles per parcel using the 'nParticle' control. The presence of this control is used to determine whether or not the number of particles per parcel is fixed, so a 'fixed' basis type is no longer needed. A number of bugs have been fixed with regards to lack of interoperability between the various settings in the injection models. 'uniformParcelSize' can be changed freely and the number of parcels and amount of mass that an injector introduces will not change (this was not true of 'parcelBasisType'). Redundant settings are no longer read by the injection models; e.g., mass is not read if the number of particles per parcel is fixed, duration is not specified for steady tracking, etc... The 'inflationInjection' model has been removed as there are no examples of its usage, its purpose was not clearly documented, and it was not obvious how it should be updated as a result of these changes.
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