Comparison of the Behavior of Different Jet Configurations in a Crossflow

In this study, the well understood single round jet in crossflow is compared to an array of three jets aligned on the central axis of the crossflow, all of which are distinct with independent temperature and flow control. The benefit of this study is to better understand how an array of jets mix with a crossflow in turbulent conditions in an effort to further validate computation models for a variety of multiple-jet applications. The test section involves jets issuing vertically downward into a cross flow provided by a low speed wind tunnel. The jets are spaced two diameters apart, providing for an upstream, middle, and downstream jet. The hydraulic interactions are tracked via a stereoscopic particle image velocimetry (S-PIV) system. Several reference measurements and the uncertainty of the results are discussed to aid analogous computational fluid dynamics (CFD) models in the future. First order statistics between the single and triple jet cases with fixed flow rates are compared. Temporal analysis yields dominant frequencies at distinct regions within the flow. Insights into flow control of multiple jets in a cross flow is discussed. The experimental data sets compare the classical single jet in cross flow to the extension of multiple jets. Several differences in the flow behavior are found. The data sets serve as benchmark cases for future CFD models that will aim to replicate these flow types in different real-world applications such as coolant flows in a gas cooled reactor.