(54e) Deposition Rate Consequences of the Formation of Multi-Spherule Cluster Aggregates in Gases "Role of Momentum ShieldingTM"
World Congress on Particle Technology
Tuesday, April 24, 2018 - 11:45am to 1:15pm
This information now enables instructive engineering calculations of the deposition-rate consequences of spherule aggregation to form large cluster aggregates-----i.e. at the same mainstream spherule volume fraction we can now determine how much aggregation will increase or decrease the total spherule acquisition rate on an immersed target. We present here representative results for each of the abovementioned particle transport mechanisms----i.e.: i) isothermal convective-diffusion (C-D), ii) thermo-phoresis (TP-) or iii) inertial impaction (II)----- including a brief account of the consequences of dealing with Kn1-dependent coagulation-âagedâ aggregate size distributions (ASDs) in the mainsteam. We summarize our current re-examination of the canonical problem of inertial impaction on a circular cylinder in Re>>1 crossflow (Rosner and Tandon (2017c), dealing now with CA-âprojectilesâ but in the absence of spherule loss from the much larger target. We conclude by briefly outlining our planned work on the efficient âinversionâ of sampled cluster-ASD-data to reconstruct, using the abovementioned Smom(N,Kn1;Df information, what ASD must have existed in the mainstream---at least in the absence of appreciable supercritical aggregate break-up.
1. Rosner, D. E. and P. Tandon (2017a). Knudsen Transition Effects on the Thermophoretic Properties of Fractal-like Aggregates; Implications for Thermophoretic Sampling of High-Pressure Flames, Aerosol Science and Technology (in press).
2. Rosner, D. E. and P. Tandon (2017b). Aggregation- and Knudsen Transition Rarefaction- Effects on Particle Mass Deposition Rates by Convective-Diffusion, Thermophoresis or Inertial Impaction; Consequences of Multi-spherule âMomentum Shieldingâ, Aerosol Science and Technology (in press).
3. Rosner, D. E. and P. Tandon (2017b). Mainstream Aggregation and Polydispersity Effects for Inertially-Dominated Deposition Rates on Cylinders (or Leading âEdgesâ) in Crossflowâ---- Consequences of âMomentum Shieldingâ for the Impaction of Large, âCompactâ (2<Df<3) Multi-spherule Aggregates, Aerosol Science and Technology (prepared for submission, August 2017).
4. Sorensen, C. M. (2011). The Mobility of Fractal Aggregates: A Review, Aerosol Science and Technology. 45: 765-779.