Chaplygin-Kármán-Tsien relation

Chaplygin-Kármán-Tsien relation

[chə′plē·gən ‚kär‚män ′tsyen ri′lā·shən]
(fluid mechanics)
The relation that in the case of isentropic flow of an ideal gas with negligible viscosity and thermal conductivity, the sum of the pressure and a constant times the reciprocal of the density of the fluid is constant along a streamline; a useful, although physically impossible, approximation.