  We present a model of center vortices, represented by closed random lines in
continuous 2+1- dimensional space- time. These random lines are modeled as
being piece-wise linear and an ensemble is generated by Monte Carlo methods.
The physical space in which the vortex lines are defined is a cuboid with
periodic boundary conditions. Besides moving, growing and shrinking of the
vortex configuration, also reconnections are allowed. Our ensemble therefore
contains not a fixed, but a variable number of closed vortex lines. This is
expected to be important for realizing the deconfining phase transition. Using
the model, we study both vortex percolation and the potential V (R) between
quark and anti-quark as a function of distance R at different vortex densities,
vortex segment lengths, reconnection conditions and at different temperatures.
We have found three deconfinement phase transitions, as a function of density,
as a function of vortex segment length, and as a function of temperature. The
model reproduces the qualitative features of confinement physics seen in SU(2)
Yang-Mills theory.
