Automatically equalizing fluid manometer combined with a computer

A set of equations, developed for the state variables of moist air, will enable flow velocity to be determined from pressure-tube measurements with increased accuracy. Conditions for this development were assumed to be those that would occur, for example, during measurements in wind tunnels. The equations were set up so that a microprocessor (also described) can automatically acquire measured values of the state variables, compute the velocity, and output the results in either analog or digital form. This new technique will significantly enhance the capabilities of a previously published measuring system for differential pressure.