The Effect of Water Droplets on the Relaxation Zone Developed Behind Strong Normal Shock Waves

Abstract

The propagation of strong normal shock waves into quiescent argon gas seeded with water droplet is studied. For evaluating the effect of the water droplets on the post shock-wave flow field, i.e., the relaxation zone, the conservation equations appropriate to a steady, one-dimensional suspension flow are formulated and solved numerically. The solution, carried out for a range of shock Mach numbers 13 ≤ M ≤ 17 and a few different values for the water droplet concentration, indicates that the presence of the water droplets has a significant effect on the extent of the relaxation zone and on the values obtained for the flow properties throughout this zone.

AEROFROSH: a shock condition calculator for multi-component fuel aerosol-laden flows

“…Their results showed that the error induced by neglecting particle volume becomes especially significant at the end of the evaporation/equilibration period, but before this time the solutions including and excluding this volume are quite similar. Rakib et al studied shock waves in water aerosols [21,22]. They found that even for very strong shocks (in this case with Mach number equal to 15), the presence of water droplets significantly reduced the post-shock temperature due to the enthalpy of vaporization.…”

“…However, if these values differ significantly, the outer loop updates the C m variable according to (5), (19), and (20), produces new gas phase mole fraction guesses via (21) and (22), and commences another iteration cycle. In these equations, x guess 2,bath,i and x guess 2,fuel are the guessed postevaporation Region 2 mole fractions of bath gas components and fuel, respectively (i is the bath gas component index); these are sent to the next cycle of the loop.…”

“…The remaining C fuel − 1 constraints come by assuming that the mole fractions of the fuel components in the evaporating droplets y fuel,droplet,j are identical to those prepared by the supplier y fuel,supplier,j , resulting in (32) (see Appendix 13.5 for a derivation of this equation). The quantity N 1,d N 1,g is still given by (20), and the bath gas mole fractions x guess 2,bath,i are still computed by (21). Finally, C m is still given in (5).…”

Normal Shock Waves in Water-Vapour Flow

“…During the experiments; the static pressure distribution along the nozzle axis, steam flow rate,static vapour temperature, and the wetness fraction at the nozzle entrance were measured. The axial pressure variation along the ǹ ozzle axis was measured by means of a Stodola search probe (3) C3f nominal diameter 3.31 mm and is equipped with a pressure trapducer (4). The probe is traversed in increments of 2 mm by rotating a calibrated dial.…”

“…[3] discussed the influence of the initial velocity and temperature lag on the flow behaviour through the relaxation zone behind a shock wave in a flow of gas-solid suspension. Also, the effect of water droplets on the flow properties through the relaxation zone developed behind strong normal shock waves was studied by Rakib and others [4] as well as by Amanbayev [5].…”