Device and method for determining the permeation rate of barrier elements and ultra-barrier elements

摘要

The invention relates to a method and a device for determining the permeation rate of barrier elements and ultra-barrier elements according to an isostatic permeation measurement method. In the process, the convective mass transfer of a permeate permeated through a barrier element is replaced by a diffusion-controlled mass transfer along a diffusion path in a subsequently arranged measurement chamber with a hollow conducting element and permeate sink.;The permeate sink ensures that permeate is removed continuously, and so a mass flux equilibrium of the permeate is set through the barrier element and through the diffusion path.;The concentration gradient of the permeate and, from this, the permeation rate of the barrier element is then determined by non-invasive determination of the concentration of the permeate along the diffusion path.

主权项

1. Device for determining the permeation rate of a barrier element, in which
a barrier element (2), at least in sections, forms a separation with a permeable cross-sectional area AB between a test gas space (1) and a measurement chamber (3), the test gas space (1) containing a gas, to be permeated, at constant partial pressure, characterized in that at least one hollow conducting element (4) with a permeate sink (5) is arranged or formed on the measurement chamber (3) in such a way that a flow-free diffusion path (11), through which a permeate can diffuse, is formed starting from the barrier element (2), through the hollow conducting element (4), up to the permeate sink (5), wherein the hollow conducting element (4) has a cross-sectional area AG, modified compared to the cross-sectional area AB at at least one position, with the permeate concentration being measurable in a non-invasive fashion using at least one detector (8,8.1,8.2) at at least one known position along the measurement chamber (3) or the hollow conducting element (4).