Va. Babenko, HOMOGENEOUS TURBULENCE EVOLUTION IN STABLY STRATIFIED FLOW .1. INTERNAL GRAVITY-WAVES AT LOW INVERSE FROUDE NUMBERS, International journal of heat and mass transfer, 40(8), 1997, pp. 1951-1961
The evolution of homogeneous grid-generated turbulence in stratified f
luid is investigated analytically. A small parameter decomposition on
inverse Froude number is applied to the theory of nearly homogeneous t
urbulence developed earlier in refs. [1] and [2]. Applying the multipl
e scale method we calculate the frequency and amplitude of internal gr
avity waves and formulate differential system describing the wave-aver
aged behaviour of turbulence characteristics. The comparison with the
numerical results published in (?1 and with known experimental data sh
ows a very good agreement as to internal waves as to small scale turbu
lence in collapsed state. The long-term turbulence evolution in weakly
stratified media can be regarded as a singular perturbation problem p
ermitting us to gain an insight into the interaction between gravity w
aves and active turbulence. (C) 1997 Elsevier Science Ltd.