caa a22 4500 606199047 CHVBK 20210128100936.0 cr unu---uuuuu 210128e20151101xx s 000 0 eng 10.1007/s00348-015-2070-z doi (NATIONALLICENCE)springer-10.1007/s00348-015-2070-z On the trajectory scaling of tandem twin jets in cross-flow in close proximity [Elektronische Daten] [T. New, B. Zang] An experimental study has been conducted on tandem twin jets in cross-flow (JICF) in close proximity to investigate the relationships between their trajectories, separation distances and velocity ratios. Results show that the front and rear jets, each with initially distinct jet trajectory, merge into a single trajectory shortly after they exhaust into the cross-flow. Furthermore, the merged tandem JICF attains deeper cross-flow penetration than that of a single JICF at the same velocity ratio. The front jet is also observed to provide ‘shielding' for the rear jet such that the latter penetrates relatively deeper into the cross-flow, which corroborates observations made by earlier studies. In particular, the present study demonstrates that it is possible to collapse the tandem JICF merged trajectories by ‘rD'-scaling, where A and B coefficients show slight reductions and increments, respectively, with increasing separation distance. Collapsing the merged trajectories by using single JICF A and B coefficients leads to the notion of effective velocity ratio for tandem JICF, which enable the authors to propose a modification in the ‘rD'-scaling law for tandem JICF. Lastly, the modified ‘rD'-scaling law is applied to trajectory data from an earlier tandem JICF study, and its validity is demonstrated by the resulting good collapse. Springer-Verlag Berlin Heidelberg, 2015 New T. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, Singapore aut Zang B. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, Singapore aut Experiments in Fluids Springer Berlin Heidelberg 56/11(2015-11-01), 1-12 0723-4864 56:11<1 2015 56 348 https://doi.org/10.1007/s00348-015-2070-z text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00348-015-2070-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- New T. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, Singapore aut NATIONALLICENCE 700 1- Zang B. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, Singapore aut NATIONALLICENCE 773 0- Experiments in Fluids Springer Berlin Heidelberg 56/11(2015-11-01), 1-12 0723-4864 56:11<1 2015 56 348