modelLotkaVolterra

Lotka Volterra prey-predator behaviour

Information

Predator-Prey Interaction (Lotka-Volterra)

This example has been taken from the PowerDEVS software.

The Lotka-Volterra equations describe an ecological predator-prey (or parasite-host) model which assumes that, for a set of fixed positive constants A (the growth rate of prey), B (the rate at which predators destroy prey), C (the death rate of predators), and D (the rate at which predators increase by consuming prey), the following conditions hold.
  1. A prey population x increases at a rate dx=A*x*dt (proportional to the number of prey) but is simultaneously destroyed by predators at a rate dx=-B*x*y*dt (proportional to the product of the numbers of prey and predators).
  2. A predator population y decreases at a rate dy=-C*y*dt (proportional to the number of predators), but increases at a rate dy=D*x*y*dt (again proportional to the product of the numbers of prey and predators).
This gives the coupled differential equations:
dx/dt=A*x-B*x*y
dy/dt=-C*y+D*x*y


Reference: http://mathworld.wolfram.com/Lotka-VolterraEquations.html


The current ModelicaDEVS predator-prey model features the following parameters: A=B=C=D=0.1


Output:

The output variable Prey represents the behaviour of the prey population, the variable Predators shows the trajectory of the predator polutation.

Components

TypeNameDefaultDescription
RealPrey
RealPredator
ModelicaDEVS.FunctionBlocks.MultiplierMult1
ModelicaDEVS.FunctionBlocks.AddAdd1
ModelicaDEVS.FunctionBlocks.AddAdd2
ModelicaDEVS.FunctionBlocks.IntegratorIntegrator1
ModelicaDEVS.FunctionBlocks.IntegratorIntegrator2
ModelicaDEVS.Miscellaneous.worldModelworld