  The development of the classical physics fundamentals with usage of
experience of the experimental and computational-analytical investigations has
allowed to create the valid conception of a fluid motion. The multidisciplinary
approach on a new basis has allowed to ensure the physical adequacy to a
mathematical model of the gas flow with allowance for essential nonlinearity of
change of the gas stream main parameters and the metering characteristics of
the flow elements of the type: pipe, pipeline, convergent nozzle and also with
allowance for the evolutional character of the gas flow structure before a
setting, in the itself flow element and in jet flowing out from one. The
example of the valid solution of the direct and inverse problems about a gas
flow through the flow element is given for the first time. The results of the
solution by amount, kind and precision of the obtained information are an
example of the satisfactory solution of the gas dynamics problem.
