SIMULATION OF THE VAPORIZATION PROCESS IN INDUCTIVELY-COUPLED PLASMA-ATOMIC EMISSION-SPECTROMETRY WITH A MODIFIED-MODEL USING THE MONTE-CARLO TECHNIQUE

An improved Monte Carlo program based on the velocity model and two-te mperature model for the simulation of the aerosol vaporization process in an inductively coupled plasma (ICP) is presented. The influence of carrier gas flow rate, Q(g), on the useful mass transport rate, W(u), and the influence of Q(g) on W(u) at a given observation height above the load coil are studied. The variation of the evaporated and unevap orated droplet numbers with Q(g) at a known observation height in the axial channel of the ICP is also presented. The results confirm experi mental observations that carrier gas flow rate and observation height are the critical parameters in controlling W(u) and hence, in large pa rt, the observed emission signal. As expected, the quality of the aero sol input is also shown to be an important factor.