TimeExplicit

Solve time-dependent problems with explicit time stepping.

Syntax

model.sol(sname).create(fname,"TimeExplicit")

model.sol(sname).feature(fname).set(pname,pvalue)

Description

 Operation feature. The TimeExplicit solver is used for solving time-dependent PDEs using the classic Runge-Kutta or the Adams-Bashforth 3 explicit time-stepping schemes

Table 6-69: Valid TimeExplicit Properties

Property	Values	Default	Description
clist	String array		Provide values for constants as input parameters using a string array; for the corresponding constant names, use cname.
cname	String array		Provide names of constants as input parameters using a string array; for the corresponding constant values, use clist.
control	String	user	Name of the controlling study step or "user" if the feature is controlled manually.
erkorder	integer between 1 and 4	4	Runge-Kutta order.
exprs	String		Expression for time stepping when tstepping=elemexprs.
keeplog	on | off	off	Keep warnings in stored log.
linsolver			Linear solver
message	String		The log message from the last solution process.
odesolver	erk | ab3 | ab3loc	erk	Time explicit solver.
plot	on | off	off	Plot while solving.
plotfreq	tsteps | tout	tout	Times to update plot.
plotgroup	String		Name of plot group for plot while solving.
probefreq	tsteps | tout	tsteps	Times to update probe.
probes	vector of strings		Probed to use if probesel=manual.
probesel	all | none | manual	all	The probes to compute.
rktimestep	positive scalar	1e-3	Time step.
solfile	on | off	on	Store solution out-of-core.
storeudot	on | off	on	Store time-derivatives.
tlist	vector of strings		Specified time list.
tout	tsteps | tlist	tlist	Times to store in solution.
tstepping	manual | elemexprs	manual	Manual or from expressions time stepping.

The order of the Runge-Kutta method can be set by the erkorder property. The size of the time step is controlled through the property rktimestep and can be given as a single scalar value, a (strictly monotone) numeric vector, or an expression using variables with global scope, which results in a scalar. For Adams-Bashforth 3 only a scalar constant value of the time step is allowed. Time stepping from expressions tstepping=elemexprs is useful for the Wave form PDE interface. A local time stepping version of Adams-Bashforth 3 is available for the Wave form PDE interface by odesolver=ab3loc.