ABAQUS CEL and acoustics problem

Hello everyone!

 I am trying to complete 2 separate analyses which i would love to get some advice on.

The first one is a CEL model in which i am aiming to test the dispersion of one fluid into another as one is slowly introduced into the other. I feel i understand what theory i need to know to model this problem and have the model ready to go, however when i try to solve it complains that one of my eularian components is not fully meshed, i have meshed and remeshed the component over and over to no avail. The component has a diffferent appearance in the mesh module from other components (see image), and is partitioned so as to assign initial material/void condition. To ensure that the unfull meshing wasnt being caused by the partitions i have tried multiple meshing approaches (bottom up meshing cell by cell or the instance as a whole) however the problem persists. One thing i have considered as a possible solution is the mesh-geometry association, however i do not know enough about this tool and this issue feels like a simple fix that i cannot seem to spot, has anyone else had a similar issue??

The second simulation is an acoustic model....this i am still in the theory phase and was hoping to gain some advice. I am simply trying to simulate the motion of a haptic feedback device (that is a linear resonance actuator) and model it's effect on a structure at different powers. It oscillates around 100 Hz. I am unsure what steps to use and wether acoustic elements are entirely neccesary. from what i understand the (linear peturbation-> frequency) step to apply a frequency and then  linear perturbation  ->steady state dynamics, direct) in order to analyse the effect on the structre. However, there is never any reference to applying the load to the set at which i hope to oscillate. can anyone offer a general workflow?

Hope this all makes sense, i know it's a very long post. Ive been going round in circles with these for a while so wanted to be very clear, any help is greatly greatly appreciated!

over and out,

Coz