THE QUASI-STEADY APPROXIMATION IN SPEECH PRODUCTION

Because boundary-layer separation is important in determining force be tween flowing air and solid bodies and separation can be sensitive to unsteadiness, the quasisteady approximation needs to be examined for t he flow-induced oscillations of speech (e.g., phonation and trills). A review of the literature shows that vibratory phenomena, such as phon ation and tongue-tip trills, may need to be modeled without the quasis teady approximation.