Portal de Periódicos da CAPES

Changes in the Vibrational Napier (Relaxation) Time of Methane-Water-Vapor Mixtures

1967; Acoustical Society of America; Volume: 42; Issue: 1 Linguagem: Inglês

10.1121/1.1910562

1520-9024

Alan A. Monkewicz,

Atomic and Subatomic Physics Research

Using a modified Hubbard low-pressure acoustic interferometer, the velocity dispersion of methane-water-vapor mixtures was measured as a function of (f/p). The napier time of the mixture was determined from these measurements. From this it was possible to obtain values of the napier time of the mixtures as a function of the mole percent of water vapor present. These values show a nonlinear dependence on the percent mole fraction. The results were subjected to an analysis similar to that of Tuesday and Boudart, an analysis that is based on two postulates: a “resonance” between methane and water vapor and rapid de-excitation of water vapor by itself. Numerical solution of the resulting equation kTτP−K10+(K20−K10)X+K30X[K50+(K40−K50)X(K03+K50)+(K40−K03−K50)X] yielded a quadratic dependence of the napier time on the mole fraction of water vapor similar to the case of oxygen-water mixture. Reaction rates for the five possible reactions in a binary gas mixture were obtained. Since these reaction rates are the reciprocals of the napier times, the collisions numbers were also obtained. When the collision numbers obtained are compared with those of other investigators, the agreement is found to be very good, particularly for water vapor.