Preliminary Numerical Modelling of Non-Newtonian Fluid Behaviour Under Surface Microwaves

This paper presents the numerical simulation of a non-Newtonian fluid under the effect of moving sinusoidal surface micro waves generated by a micro actuator. The blood is used as the fluid in the simulation, which is confined between the actuator and the substrate, within a channel of 20 micron high. The simulation was solved using the finite element method by utilizing the commercially available software ANSYS. A mathematical model is developed to convert the non-Newtonian fluid to equivalent Newtonian fluid to estimate the traction force. The results show that a stable thrust force is generated by the moving sinusoidal waves. The magnitude of the thrust force is increasing while the fluid viscosity and the wave frequency are increasing. The results also show that the thrust force is highly predictable and controllable. A surface thrust force of 19.71 micro-Newton per centimetre for the frequency of 1 kilohertz can be obtained in blood by using an actuator of one millimeter diameter. The direction of the force can be changed by changing the wave propagation direction.