Interaction of heated filaments with a blunt cylinder in supersonic flow

A computational study is performed to examine the influence of pulsed energy deposition on a cylinder in supersonic flow. A code is written to solve the compressible Navier–Stokes equations. The energy deposition is modeled as a high temperature, low density filament introduced at the inflow boundary, and the frequency of energy deposition pulses is varied. It is shown that the energy deposition reduces both the average drag and the average heat transfer to the front face of the cylinder. The effectiveness of drag reduction is shown to be inversely proportional to the energy deposition pulsation period. The efficiency of drag reduction is shown to be approximately 100. The average heat transfer to the face is reduced from the steady state, with a maximum reduction of 30%.     

Radiative collisions and two-photon transitions

We explore the heuristic connections between laser-induced energy transfer in radiative collisions and a simple two photon transition involving two near-resonant fields.     

Neutron activation analysis of wear products in a Diesel engine fueled with coal-oil slurries

The technique described is a stable tracer method and has the advantage of eliminating the use of radioactive engine components during the wear tests. The results obtained clearly show that the use of these slurries comprising pulverized coal and fuel oil is not acceptable due to excessive wear rates.     

Photophysics of the B̃ 1A1 state of thiophosgene

The results of fluorescence lifetime measurements using a dye laser excitation source are combined with other recently published data to present a consistent picture of the photophysics of the B? ¹A₁ state of Cl₂CS.