simecol (version 0.8-2)

chemostat: Chemostat Model

Description

simecol example: Model of continuos culture of microorganisms (chemostat).

Usage

data(chemostat)

See Also

simecol-package, sim, parms, init, times.

Examples

##============================================
## Basic Usage:
##   work with the example
##============================================
data(chemostat)
plot(sim(chemostat))

parms(chemostat)["D"] <- 0.9 
plot(sim(chemostat))



##============================================
## Implementation:
##   The code of the chemostat model
##============================================
chemostat <- new("odeModel",
  main = function(time, init, parms, inputs = NULL) {
    with(as.list(c(init, parms)), {
      mu  <- vm * S/(km + S)              # Monod equation
      dx1 <- mu * X - D * X               # cells, e.g. algae
      dx2 <-  D *(S0 - S) - 1/Y * mu * X  # substrate, e.g. phosphorus
      list(c(dx1, dx2))
    })
  },
  parms = c(
    vm = 1.0,           # max growth rate, 1/d
    km = 2.0,           # half saturation constant, mumol / L
    Y  = 100,           # cells /mumol Substrate
    D  = 0.5,           # dilution rate, 1/d
    S0 = 10             # substrate in inflow, mumol / L
  ),
  times = c(from=0, to=40, by=.5),
  init  = c(X=10, S=10), # cells / L; Substrate umol / L
  solver = "lsoda"
)