The spectral energy distributions of AGN have a characteristic double-hump structure, with emission at the lower wavelengths being dominated by synchrotron emission from non-thermal electrons in a relativistic jet. In order to investigate possible causes of variability in these systems we model the synchrotron emission from relativistic jets using a 3D hydrodynamic simulation. The simulation was run using the grid based hydrodynamic code PLUTO. The model setup for the simulation consisted of a uniform background medium with less dense jet material injected, at a constant rate, with a Lorentz factor of $\Gamma=10$. Post-processing calculations were applied to the simulation in order to produce 2D intensity maps at 15 GHz. For this emission we assumed that all of the jet particles had a power-law distribution with no cooling effects. A delta-approximation model was setup to calculate the synchrotron emission and absorption coefficients, and these were then integrated along a user defined line of sight to produce intensity maps. The simulation was evolved until just before the working surface of the jet left the computational domain. The intensity plots show the formation of multiple emission regions at the head of the jet along with a varying intensity.