PP module
- PP.pebble_predictor(snowline_i=numpy.zeros, **pars)
Returns estimates of pebble Stokes number and flux from disk.
This has been modifed by S. McCloat to work directly with the PPOLs Model code. Main modification incorporates a snow line and changes to dust surface density, dust/gas fraction. Also introduces tracking of eta and Hgas over time for gas evolution, but not yet implemented.
User inputs disk properties and PP returns estimates of pebble Stokes number St(t,r) and pebble flux Mdot_p(t,r) [g/s] at every time (tgrid) and location (rgrid).
- Parameters:
- rgridndarray
Radial grid positions for disk. [cm]
- tgridndarray
Time grid for “lifetime” of disk model. [s]
- Mstarfloat
Mass of the central star. [g]
- SigmaGas, SigmaDustndarray
Initial gas, dust surface density at every point of rgrid. Must be same size as rgrid. [g/cm^2]
- Tndarray
Gas temperature at every point of rgrid. [K]
- alphafloat
Turbulence strength parameter.
- vfragfloat
Collisional fragmentation threshold velocity. [cm/s]
- rhopfloat
Bulk density of dust grains. [g/cm^3]
- Returns:
- stndarray
Flux-averaged Stokes value of pebbles at each [t,r].
- fluxndarray
Estimated pebble mass flux (i.e. Mdot_p[t,r]).
- etaIndarray
Initial and constant gas pressure gradient. Negative values.
- HgasIndarray
Initial and constant gas scale height. [cm]
- fDGndarray
Dust/Gas fraction, averaged across rgrid for each t.
- hgas_temptest, etas_temptestndarray
Experimental arrays that record eta, hgas, over [t,r] instead of just [r]. Intended for future implementation of gas evolution.
Notes
The base and fundamental action of pebble_predictor (PP) comes from Drazkowska et al. (2021), and interested readers are directed there for full technical details. PP is modified here to incorporate a snow line and related changes, and return more parameters.