This report covers work on two unrelated tasks. The first was an investigation of the formulation of the equations for non-uniform unsteady flows, by perturbation of an irrotational flow to obtain the linear Green's equation. For the uniform flow case, this kernel was found to limit to the doublet form commonly used in formulating the flutter problem. It is believed that the non-uniform flow effects may prove important in transonic flutter and that in such cases, the use of doublet type solutions of the wave equation would then prove to be erroneous. The second task covered an initial investigation into the use of the Monte Carlo method for solute in of acoustical field problems. Computed results are given for a rectangular room problem, and for a problem involving a circular duct with a source located at the closed end. In both cases, results appear to be within statistical expectations, although statistical deviations were large because computer time was limited. The most severe limitation to further applications of the method is the need for a suitable method to handle acoustical diffraction, as in a shadow zone, or near a window in a room.
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