UQ eSpace

Abstract

Simulation which incorporates numerical method is practical in investigating the effect of ultrasonic excitations on the acoustic pressure and flow patterns of fluid with arbitrary settings as it can produce reliable results in a relatively short time even for complex cases. This thesis aims to develop efficient simulation of acoustic pressure field generated by ultrasonic transducer using ANSYS Workbench to obtain accurate data of the resulting flow and pressure fields for harmonic ultrasonic excitations. Simulation methodology is developed from reviewing literatures and it is used as a basis to simulate and replicate results from two distinct literatures for validation purpose. An arbitrary simple case is simulated to gauge the effectiveness of simulation made based on the established simulation methodology in investigating acoustic pressure field. Through these processes, the following are concluded: • Computation effort increases with higher number of degrees of freedom (DOF) of nodes involved in solving process. • Mesh quality should be decent, and the element size should follow the meshing guidelines to ensure accurate results. • Appropriate assumption of boundary conditions of experimental setup is important to ensure feasibility of simulation results. • Simple simulation model is better than complex model in both result accuracy and computation time when there is insufficient information on the case to be simulated. • Model reduction via plane/axis of symmetry and use of 2D/2.5D models should be prioritised for fast and accurate simulation.

In situ green synthesis of Cu‐Ni bimetallic nanoparticles supported on reduced graphene oxide as an effective and recyclable catalyst for the synthesis of N‐benzyl‐N‐aryl‐5‐amino‐1H‐tetrazoles

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