Pressure Distribution and Membrane Deflection During EO
The pressure distribution during EO is a little counter-intuitive. Assuming no back pressure, and neglecting the effects of the meniscus on either end of an EO channel, the pressure distribution relative to the (left-to-right) direction of flow must look something like …
The counter-intuitive part is that the pressure drop across the membrane opposes the EO flow. Of course this has to be true of any pump that takes in a low pressure fluid and puts out a high pressure fluid. But here the flow in the pores is moving toward the high pressure side of the membrane!
Confirming a point made Professor Mcaleavey as reported in a recent post by Karl, the membrane should deflect away from the direction of flow during EO …
Also not an intuitive picture.
Interesting.
I guess you could look at this as the “flow moving toward the high pressure side”, but isn’t it the flow itself that creates the pressure differential? I don’t think the membrane has to do any pushing, the applied E-field does that. However, as a result, there is a pressure differential that deflects the membrane. Maybe these effects cannot be truly separated, but that’s how I look at it…
Thanks!