Experimental Based Empirical Model Of The Initial Onset Of Sand Deposits On Hastelloy-X From 1000 Degrees C To 1100 Degrees C Using Particle Tracking

Deposition experiments are performed on a Hastelloy-X coupon using Arizona Road Test Dust (ARD). A statistical empirical model of the initial onset of ARD deposits is developed from the experimental data. The initial onset of deposits are a quadratic function of local surface temperature and impact velocity components (normal and tangential). A prominent observation is that tangential impact velocity has a significant non-linear, independent effect on deposits relative to normal impact velocity and local surface temperatures. All experiments use 20-40 mu m ARD on a bare metal surface over a 1000-1100 degrees C range. Unlike prior mass-based deposit studies, initial deposits for this study are quantified using a Coverage Ratio (CR), which is the area covered by deposits relative to the total area available. The empirical CR model has a strong correlation to coupon surface temperature and impact velocity vectors and is a foundation for future numerical or experimental model comparisons.