EXPERIMENTAL AND NUMERICAL STUDY OF AN INCINERATOR-RELATED AND FURNACE-RELATED FLOW

The results of an experimental and computational study of the flow ove r a separation-inducing corner formed by a surface-mounted, triangular obstacle located close to a 90 degrees turn are presented. The study was undertaken as part of a process to develop and validate numerical simulation methods for predicting incinerator and furnace flows, and t he flow configuration studied is characteristic of such devices. The p redictions from FEM simulations based on the standard k-epsilon turbul ence model are compared with results from two-component LDV measuremen ts from a water tunnel experiment. In the numerical simulations, two d ifferent outflow boundary conditions are used, one being the stress-fr ee outflow condition and the other making use of special outflow eleme nts. The results from the numerical simulation with the special outflo w elements are in better agreement with the experimental results than those from the simulation with the stress-free outflow boundary condit ion. With the special outflow elements, the mean velocities and the gr adients of the mean vertical velocity are well predicted. In the regio n separating the recirculation zone from the freestream where turbulen t transport is most important, good agreement between the experiment a nd the special outflow elements simulation is achieved for the turbule nt kinetic energy.