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The high temperature ignition of C1-C4 primary alcohols, methanol, ethanol, n-propanol, and n-butanol, is studied behind reflected shock waves. The experiments are carried out at pressures of 2, 10, and 12 atm with argon/oxygen ratios of 10, 15, and 20 under lean, φ = 0.5, stoichiometric, φ = 1, and rich, φ = 2, conditions between 1070 and 1760 K. It is observed that the ignition delay time data for ethanol, n-propanol, and n-butanol collapse under conditions of constant equivalence ratio, pressure, and dilution. The ignition delay times of methanol are comparable with the other alcohols but show a slightly lower activation energy than the other fuels. The observed collapse of the ignition delay times for the four alcohols under lean-to-stoichiometric conditions is comparable with recent observations by Veloo et al.

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An experimental and numerical study of impinging, incompressible, axisymmetric, laminar jets is described, where the jet axis of symmetry is aligned normal to the wall. Particle streak velocimetry ͑PSV͒ is used to measure axial velocities along the centerline of the flow field. The jet-nozzle pressure drop is measured simultaneously and determines the Bernoulli velocity. The flow field is simulated numerically by an axisymmetric Navier-Stokes spectral-element code, an axisymmetric potential-flow model, and an axisymmetric onedimensional stream-function approximation. The axisymmetric viscous and potential-flow simulations include the nozzle in the solution domain, allowing nozzle-wall proximity effects to be investigated. Scaling the centerline axial velocity by the Bernoulli velocity collapses the experimental velocity profiles onto a single curve that is independent of the nozzle-to-plate separation distance. Axisymmetric direct numerical simulations yield good agreement with experiment and confirm the velocity profile scaling. Potential-flow simulations reproduce the collapse of the data; however, viscous effects result in disagreement with experiment. Axisymmetric one-dimensional stream-function simulations can predict the flow in the stagnation region if the boundary conditions are correctly specified. The scaled axial velocity profiles are well characterized by an error function with one Reynolds-number-dependent parameter. Rescaling the wall-normal distance by the boundary-layer displacement-thickness-corrected diameter yields a collapse of the data onto a single curve that is independent of the Reynolds number. These scalings allow the specification of an analytical expression for the velocity profile of an impinging laminar jet over the Reynolds number range investigated of 200ഛ Re ഛ 1400.