Experiments and CFD model development for wall condensation on containment structuresCopyright: © Eva Groß
The Separate Effect Test for Condensation Modeling (SETCOM) facility (see Fig. 1) was designed and constructed to provide CFD grade data for the development and validation of wall condensation models. The facility is essentially a closed loop, which allows steady state operation with reproducible boundary conditions. In order to ensure optimal use for CFD model D&V, comprehensive efforts have been made to design the facility components in order to realize well-known boundary conditions that can be directly transferred to the CFD model without (major) further assumptions. Consequently, the SETCOM test section consists of a rectangular flow channel (0,44 m x 0,44 m) with three adiabatic walls, which are electrically heated to balance heat losses (see Fig. 2 right). The 6 m long cooling plate, manufactured from the aluminum alloy AlMg4,5Mn, is designed as a water cooled counter current cross-flow heat exchanger, which allows for a nearly uniform wall temperature (Delta T < 2 K) along the entire cooling plate. It can be modeled in a conjugate heat transfer approach by specifying a measured secondary coolant temperature and characterized heat transfer coefficient. A detailed 3D characterization of the inlet conditions, i.e. velocity, turbulence intensity, gas temperature and humidity fields revealed that both baffles in the flow redirection and a specially designed grid type flow conditioner lead to a nearly constant velocity over the whole inlet cross section of the condensation channel. The SETCOM facility can be inclined between a horizontal to a vertical position (see Fig. 2 left) in order to allow for a detailed investigation of buoyancy effects in mixed convection flows. The facility periphery allows to specify gas temperatures up to 100°C, wall temperatures around 10°C, a gas humidity up to 99% and flow velocities between 0.5 m/s and 5 m/s. The commercial process control system DeltaV TM from Emerson Process Management is used for facility operation and data acquisition. It allows for a precise definition of steady and reproducible boundary conditions.
Copyright: © Stephan Kelm
In the CEC project 150 1404, the Separate Effect Test for Condensation Modeling (SETCOM) test facility was therefore designed with the aim of collecting suitable measurement data in the boundary layer in order to develop wall functions for condensing flows. In the post-project 150 1489, the facility and its instrumentation were systematically improved and quantitative 'CFD-grade' measurements were performed for the first time.
The focus in the current SETCOM2 project (GRS project no. 1501591) will be on further improvement of velocity measurements in the viscous sublayer and the aim to further collect a complete set of CFD grade data for model validation. Therefore, a new measurement technique, the LDV profile sensor, with promising high spatial resolution, was upgraded to the facility.
2019/04 – 2022/03
Prof. Hans Josef Allelein, IEK-6 Jülich Research Centre
Dr.-Ing. Stephan Kelm, IEK-6 Jülich Research Centre
German Federal Ministry for Economic Affairs and Energy (Project No. 1501591)