Output files

uDALES writes its outputs as NetCDF files. Simulations run on more than one CPU write one file per CPU for most output types; files that are already reduced across the whole domain (e.g. the y-, xy- and xy-time-averaged statistics, the TKE budget and the facet energy balance files) are written once, by rank 0. Per-CPU files use the naming pattern <name>.<px>.<py>.<expnr>.nc, where <px> and <py> are the three-digit x- and y-pencil ranks; reduced files use <name>.<expnr>.nc. Use gather_outputs.sh (or its HPC/ARCHER2 wrappers) to merge the per-CPU files into single files per experiment — see Post-processing.

All switches and frequency parameters below live in the &OUTPUT, &TREES, &WALLS and &ENERGYBALANCE namelists of namoptions; see the Configuration page for their defaults and constraints.

Output files

File	Enabled by	Frequency	Contents
Statistics (time- and/or space-averaged)
tdump.<px>.<py>.<expnr>.nc	ltdump	tstatsdump	Time-averaged 3D statistics per CPU: mean velocity, temperature, moisture, pressure and scalar fields; PSS defect; turbulent momentum/heat/scalar fluxes; variances and TKE; SGS scalar fluxes.
mintdump.<px>.<py>.<expnr>.nc	lmintdump	tstatsdump	Reduced time-averaged 3D statistics per CPU: mean u, v, w, temperature and moisture, and pressure only (lighter-weight alternative to tdump).
xytdump.<expnr>.nc	lxytdump	tstatsdump	x-, y- and time-averaged 1D (height) statistics: mean velocity/temperature/moisture/pressure profiles, turbulent/kinematic/SGS fluxes, temperature and momentum variances, TKE.
xydump.<expnr>.nc	lxydump	tsample	x- and y-averaged instantaneous 1D (height) profiles: velocity, temperature, moisture, pressure, turbulent/SGS momentum and heat fluxes, advective fluxes.
ytdump.<expnr>.nc	lytdump	tstatsdump	y- and time-averaged 2D (x, height) statistics: mean velocity/temperature/moisture/scalar profiles, turbulent/kinematic/SGS fluxes, variances. Only functional if the x-direction is not parallelised.
ydump.<expnr>.nc	lydump	tsample	y-averaged instantaneous 2D (x, height) profiles: velocity, temperature, moisture, scalars, turbulent/SGS momentum and heat fluxes, advective fluxes. Only functional if the x-direction is not parallelised.
tkedump.<expnr>.nc	ltkedump	tstatsdump	xy-averaged TKE budget terms vs. height: buoyancy production, total transport, advection, turbulent transport, SGS transport, shear production, viscous and SGS dissipation. Currently marked unsupported in the namoptions documentation — treat as experimental.
treedump.<px>.<py>.<expnr>.nc	ltreedump (&TREES)	tstatsdump	Time-averaged 3D vegetation/tree terms per CPU: drag in x, y, z; temperature and moisture source/sink terms; scalar source/sink terms; decoupling factor.
Instantaneous fields
fielddump.<px>.<py>.<expnr>.nc	lfielddump	tfielddump	Instantaneous 3D snapshots of the variables listed in fieldvars (e.g. velocity components, temperature, moisture, pressure, scalars, wall stresses, heat flux, IBM masks, divergence), per CPU.
Slices
kslicedump.<px>.<py>.<expnr>.nc	lkslicedump	tsample	Instantaneous horizontal (x, y) slice at k = kslice of u, v, w, temperature and moisture, per CPU.
islicedump.<px>.<py>.<expnr>.nc	lislicedump	tsample	Instantaneous vertical (y, z) slice at i = islice of u, v, w, temperature and moisture; written only by the CPU(s) owning that i-index.
jslicedump.<px>.<py>.<expnr>.nc	ljslicedump	tsample	Instantaneous vertical (x, z) slice at j = jslice of u, v, w, temperature and moisture; written only by the CPU(s) owning that j-index.
Facets
fac.<expnr>.nc	lwritefac (&WALLS)	dtfac	Facet momentum and heat-transfer data per facet, averaged over the dtfac window: surface shear stresses tau_x, tau_y, tau_z, pressure and pressure fluctuation, heat transfer coefficients.
facT.<expnr>.nc	lwriteEBfiles (requires lEB)	dtEB	Facet layer temperature (T) and temperature gradient (dTdz) per facet and facet layer.
facEB.<expnr>.nc	lwriteEBfiles (requires lEB)	dtEB	Facet surface energy-balance terms per facet: net shortwave, incoming longwave, outgoing longwave, sensible heat flux, latent heat flux, soil water content.

Statistics that are sampled every tsample and only dumped every tstatsdump (tdump, mintdump, xytdump, ytdump, treedump, tkedump) report the average over the preceding tstatsdump window; the switches whose frequency is tsample (xydump, ydump, the slice dumps) instead write an instantaneous sample every tsample. Sampling/averaging only starts once the simulation time passes tstatstart.

Restart files

If trestart is smaller than runtime, uDALES periodically writes unformatted (non-NetCDF) restart files per CPU: initd<ntrun>_<px>_<py>.<expnr> holds the flow fields (mindist, wall, u0, v0, w0, pres0, thl0, e120, ekm, qt0, ql0, ql0h, plus the current time and timestep), and, if nsv > 0, a companion inits<ntrun>_<px>_<py>.<expnr> holds the scalar fields sv0. ntrun is an 8-digit run counter embedded in the filename. These are written by writerestartfiles in modsave.f90, at the interval set by trestart, and additionally whenever an exit_now.<expnr> file is detected or (for driver simulations) when the inlet file store is exhausted.

To resume from a restart file, set lwarmstart = .true. (or lstratstart = .true.) and point startfile at the initd... filename of the desired restart point (the trailing digits of startfile must match the experiment's iexpnr); the matching inits... file, if present, is read automatically. See the RUN and SCALARS namelists on the Configuration page for the exact parameter definitions.