ISOLATED FLUID OXYGEN DROP BEHAVIOR IN FLUID HYDROGEN AT ROCKET CHAMBER PRESSURES

A model has been developed for the behavior of an isolated fluid drop of a single compound immersed into another compound in finite, quiesce nt surroundings at supercritical conditions. The model is based upon f luctuation theory which accounts for both Soret and Dufour effects in the calculation of the transport matrix relating molar and heat fluxes to the transport properties and the thermodynamic variables. The tran sport properties have been modeled over a wide range of pressure and t emperature variation applicable to LOx-H-2 conditions in rocket chambe rs, and the form of the chemical potentials is valid for a general flu id. The equations of state have been calculated using a previously-der ived, computationally-efficient and accurate protocol. Results obtaine d for the LOx-H-2 system show that the supercritical behavior is essen tially one of diffusion. The temperature profile relaxes fastest follo wed by the density and lastly by the mass fraction profile. An effecti ve Lewis number calculated using theory derived elsewhere shows that i t is larger by approximately a factor of 40 than the traditional Lewis number. The parametric variations show that gradients increasingly pe rsist with increasing fluid drop size or pressure, and with decreasing temperature. The implication of these results upon accurate measureme nts of fluid drop size under supercritical conditions is discussed. (C ) 1998 Elsevier Science Ltd. All rights reserved.