liquid jet impingement on a porous double screen in microgravity (CFM GPPS)

research area: fluid dynamics

experiment title:

Liquid Jet Impingement at a Porous Screen
(Gas Port Phase Seperator - GPPS)

experiment acronym: CFM GPPS

funding agency: DLR

grant number: 50RL0921

performing organization:

ZARM, Universität Bremen

prime investigator: Prof. Dr. Michael Dreyer

experiment objective


For liquid propellant management in space it is sometimes important to vent gas from the fuel tank.  To this end, gas phase and liquid phase must be separated to avoid the unnecessary loss of fuel. Capillary devices have been developed to master the challenge that are based on the bubble point effect. This effect corresponds to the ability of wetted materials with small pores to resist gas cross flow up to a critical pressure difference – the bubble point. These devices work in principle. One of it is the double screen shown in the Figure. However, in the application environment, liquid fuel drops and blobs of all sizes carried by the gas flow might hit the screen. What happens then? The liquid jet impingement that we study here is a model problem to answer this question. Here we can adjust gas flow rate, liquid flow rate, amount of liquid, porous media, liquid, jet diameter and velocity.
In the course of the experiments we were able to identify critical parameters and different regimes of this configuration. The gained understanding will help to optimize the phase separation devices and in the end also improve the performance of such devices in application.

experiment campaigns

experiment year: 2012
number of catapult flights: 4

experiment year: 2011
number of catapult flights: 10