Dynamic structural and fluid flow analysis of bulk acoustic wave piezoelectric valveless micropumps are carried out for the transport of water. The micropumps consist of trapezoidal prism inlet/outlet elements; the pump chamber, a thin structural layer (Pyrex glass) and a piezoelectric transducer element (PZT-5A, PZT-4, or BaTiO3), as the actuator. Flow contraction and expansion, through the trapezoidal prism inlet and outlet respectively, generates net fluid flow. Governing equations for the flow fields and the structural-piezoelectric bi-layer membrane motions are considered. For the compressible flow formulation, an isothermal equation of state for the working fluid is employed. Two-way dynamic coupling of forces and displacements between the solid and the liquid domains in the systems are considered where actuator deflection and motion causes fluid flow and vice-versa. The effects of the piezoelectric transducer material on the flow rate are investigated for several commonly used actuators: PZT-5A, PZT-4, and BaTiO3. The net flow rate developed by the pump varies with the piezoelectric material. PZT-5A actuator generates the largest pump net flow, and the BaTiO3 actuator results in the lowest pump flow.