This thesis develops a method to model the acoustic field generated by a monopole source placed in a moving rectangular duct. The walls of the duct are assumed to be infinitesimally thin and the source is placed at the center of the duct. The total acoustic pressure is written in terms of the free-space pressure, or incident pressure, and the scattered pressure. The scattered pressure is the augmentation to the incident pressure due to the presence of the duct. It satisfies a homogeneous wave... Topics: LEAD ISOTOPES, TROPOSPHERE, BOUNDARY LAYERS, VERTICAL DISTRIBUTION, METAL IONS, NASA PROGRAMS,...
May 24, 2011byBrummell, Nicholas H.; Hurlburt, Neal E.; Toomre, Jur
The effects of rotation on turbulent, compressible convection within stellar envelopes are studied through three-dimensional numerical simulations conducted within a local f-plane model. This work seeks to understand the types of differential rotation that can be established in convective envelopes of stars like the Sun, for which recent helioseismic observations suggest an angular velocity profile with depth and latitude at variance with many theoretical predictions. This paper analyzes the... Topics: AEROSOLS, SULFURIC ACID, ASHES, COAGULATION, DILUTION, DROP SIZE, MASS RATIOS, NUCLEATION, OZONE...