What happens to air inside a blender when you turn it on?
That depends strongly on the blender's design, but usually it's going to be pushed downwards or pulled upwards.
The viscosity of the fluid (or other material) inside the blender could be important in many cases, but in case of air, it's not going to be much of a factor.
Perhaps you should refrain from trying to use engineering in your elaborate anecdotes? Your lack of understanding of how simple appliances are built really doesn't help your case. It's very difficult to understand what you're saying when you keep comparing it to your misconceptions of how household appliances work.