The addition of acoustic energy to the fluid flow can be used to increase the microchannel flow efficiency. In this paper, a 3D numerical study is carried out on a rectangular fluid cavity designed in the PDMS (Polydimethylsiloxane) material which is bonded with the Lithium Niobate (LiNbO₃) substrate. An IDT (Interdigital Transducer) made up of gold material is designed over the lithium niobate substrate for giving the acoustic effect to the fluid (here, water) flow domain. The flow parameters, such as pressure and velocity, are investigated with and without the acoustic effect. The results show that the total acoustic pressure varies from -228 Pa to 189 Pa at 25 MHz frequency compared to the maximum pressure value of 0.16 Pa without any acoustic effect. Also, the total acoustic velocity was found to vary from 2.65×10^-5 m/s to 2.21×10^-5 m/s at 25 MHz frequency which is comparatively higher to the maximum velocity obtained without any acoustic effect. At different acoustic frequencies of 15, 25 and 35 MHz, flow parameters are compared with that of laminar flow. It has been observed that both pressure and velocity enhanced after the introduction of acoustic in the flow. These results show that the microchannel flow parameters are enhanced by applying acoustic energy to the microchannel fluid flow.