公开(公告)号：US20250116591A1

公开(公告)日：2025-04-10

申请号：US18865650

申请日：2023-05-12

Applicant: AALTO UNIVERSITY FOUNDATION SR

Inventor： Mikael MIETTINEN ,  Tuomas TIAINEN ,  Valtteri VAINIO ,  Raine VIITALA

IPC: G01N15/08 ,  G01N33/34

Abstract: A device for measuring porosity and/or gas permeability of a sheet of material (9) comprises a measurement head comprising a body part (1) having a measurement face to be set towards the sheet of material, the body part comprising, on its measurement face, a first indentation defining a control volume (3) and a sealing arrangement (2, 5, 6, 7, 8) surrounding the first indentation to seal the control volume, and a control flow channel (11) forming a flow connection between the control volume and the outside of the body part for controlling the pressure in the control volume to create a pressure difference across the sheet of material to be measured. The sealing arrangement comprises a first aerostatic bearing for forming a contactless sealing between the body part (1) and the sheet of material (9) to be measured.