The presented experimental investigations of static characteristics of check valves are a contribution to work leading to improve check valve models in 1D network programs. Two designs of check valves were tested: a swing disc and a tilting disc check valve. For each type of these valves static characteristics for the two directions of water flow were performed.
Following physical quantities were measured during the experiments: the angular position of the valve closing element (disc), water discharge, pressure losses caused by the check valve, moment of the hydrodynamic forces acting on the valve disc and pressure at selected locations of the flow system of the test rig.
The paper describes the test rig designed for developing the static characteristics of the check valves and presents the results of tests for the characteristics of the swing and tilting disc check valve under steady flow conditions. These characteristics are presented as time-averaged parameters measured during the tests. Following dimensionless quantities are calculated basing on these parameters:
- the flow rate coefficient,
- the coefficient of the moment of hydrodynamic forces acting on the valve disc,
- the local loss coefficient of the valve.
The above-mentioned coefficients were determined for disc angular position of selected values (opening rate) and interpolated within the full range of openings for both directions of flow through the valve.
The static behaviors of the tested valves are discussed and compared with each other.