We show that in an unsteady Poiseuille flow of a Navier-Stokes fluid in an infinite straight pipe of constant cross-section, σ, the flow rate, F (t), and the axial pressure drop, q(t), are related, at each time t, by a linear Volterra integral equation of the second type, where the kernel depends only upon t and σ. One significant consequence of this result is that it allows us to prove that the inverse parabolic problem of finding a Poiseuille flow corresponding to a given F (t) is equivalent to the resolution of the classical initial-boundary value problem for the heat equation. (2000). 35Q30, 76D03, 76D05.
Mathematics Subject Classification