Hh = absolute viscosity of the fluid dg =d= Gd! ad! - 3,3 —_4_ & #,(P-8 / = liniting diame- ter to which the streamline law applies @ = acceleration due to gravity The values for K,, Kp and P were given as determined for irregular quartz perticles, which for this application is more suitable than those velues given for spherical particles. The vilue of Ky was determined by solving the Eqs. E.] end E.2 at the point of transition (85) from streamline motion to the intermediate region.2/ The density of the particle was determined experimentally for actual fzllout particles collected in the field (see Section 5.4). The densityYof the air and the viscosityl3/of the air which is temperature dependent are shown in Table E.1. The values for the viscosity are based on temperature mexsurements tiken in the Bikini area at Shot 1 time by the Task Force eather Central, Temreriture data were not taken for altitudes above 50,000 ft, so the tempersture above that elevetion Wes assimed to be isothermal. Since choice of the applicuble equation is dependent upon the type of motion experienced by particles felling through air, it was necessary to determine the limiting diameters to which the various laws apply. The expression for the limiting diameter to which the streamline law applies was given above. The expression for the intermediate region, dt = 23.5[ /? & P,(P-A) was available from another source.®/ The caleulated values for the limiting varticle diameters at different altitudes for the tvo types of motion are =lotted in Fig. E.1. These plots define the areas in which the varjovs equations for the uetermination of terminal velocities are applicsble, It is seen th:t for some of the particle sizes considered (100, 150, 2% #) the terminal velocity calculaticns follow the intermediate law to th: altitudes indicated and beyond th:t the streamline law. Also, for the particle sizes considered from 250 to 1000 b in diazeter, it is evident thet the intermediate law only governs the terminal velocity determina- tions. when the density of the fluid is small as compcred to that of the perticle, the buoyancy correction becomes negligible and Eq, «1 takes h forn, the ' _k& ee mn- p Since the temper ture above 50,000 ft was assumed to be isothermal, the viscosity of the air remains coust.nt and the termina] velocity is proportional to the square of the diameter. Thus for a given particle 138