Engineering Papers⌕ Search

Engineering topics

Hanson, R. K.

Publications and source records attributed to Hanson, R. K..

51 records · Page 3

Experimental study of shock-wave reflection from a thermally accommodating wall.

Shock-tube experiments have been conducted to study the nonequilibrium gas-surface interaction which occurs when a thick shock wave in argon reflects from a coplanar, heat-conducting wall. Fast-response instrumentation was used to monitor variations in temperature and normal stress on the surface of the shock-tube end wall during and immediately following reflection of the incident shock wave. The laboratory observations are compared with computer predictions obtained by Deiwert using the direct-simulation Monte Carlo method, and excellent agreement is obtained when a suitable average thermal accommodation coefficient is chosen for the wall surface.

Hanson, R. K.↗

The dissociation of shock-heated carbon monoxide

Investigation of the dissociation kinetics of undiluted carbon monoxide over the 5,600 to 12,000 K temperature range. Data are presented that have been obtained as time-resolved pressure measurements on the end wall of a shock tube and radiation emission of a C2 Swan system (0-0 band) behind incident shock waves. The decomposition of CO is complex and includes a chain with C2 as an intermediate species. The dissociation rate for the overall process has been found to be independent of the proportions of the collision partners M = CO, C, and O. The rate constant found is on the average about 10 times that previously measured with argon as the collision partner.

Hanson, R. K.↗

Numerical solutions of several reflected shock-wave flow fields with nonequilibrium chemical reactions

The method of characteristics for a chemically reacting gas is used in the construction of the time-dependent, one-dimensional flow field resulting from the normal reflection of an incident shock wave at the end wall of a shock tube. Nonequilibrium chemical reactions are allowed behind both the incident and reflected shock waves. All the solutions are evaluated for oxygen, but the results are generally representative of any inviscid, nonconducting, and nonradiating diatomic gas. The solutions clearly show that: (1) both the incident- and reflected-shock chemical relaxation times are important in governing the time to attain steady state thermodynamic properties; and (2) adjacent to the end wall, an excess-entropy layer develops wherein the steady state values of all the thermodynamic variables except pressure differ significantly from their corresponding Rankine-Hugoniot equilibrium values.

Hanson, R. K.↗

Nonequilibrium shock wave structure, 1. Kinetics of nitric oxide formation and decomposition, 2

Theoretical and numerical aspects of molecular flow simulation focussed on the development of collision models for diatomic and triatomic gases undergoing rotational excitation and energy exchange. A laser absorption technique is proposed and analyzed as sufficiently sensitive for measuring rotational populations in a nonequilibrium shock wave. Also reported is a survey of available literature on NO chemical rate data in preparation for experiments on NO decompensation kinetics in atmospheric pollution.

Kruger, C. H.↗

Improved fast response pressure gauge for shock reflection studies in ionized gases.

An improved design is presented for a fast response pressure gauge (0.1 microsec risetime) suitable for short duration measurements on the end wall of a shock tube. The design includes standard components to facilitate gauge construction, and it utilizes dual capacitive sensing elements together with a signal differencing scheme to permit use of the gauge in ionized gases. Pressure-time records obtained with the gauge are presented showing details of pressure profiles on the shock tube end wall for reflecting shock waves in ionized gases.

Hanson, R. K.↗

Shock-wave reflexion in a relaxing gas

Plane normal shock wave reflection in relaxing gas for shock tube endwall upstream and downstream dynamic pressures, using method of characteristics

Hanson, R. K.↗