Imperial College London


Faculty of Natural SciencesDepartment of Mathematics

Chair in Applied Mathematics







753Huxley BuildingSouth Kensington Campus






BibTex format

author = {Qadri, UA and Schmid, PJ},
doi = {10.1103/PhysRevFluids.2.043902},
journal = {Physical Review Fluids},
title = {Effect of nonlinearities on the frequency response of a round jet},
url = {},
volume = {2},
year = {2017}

RIS format (EndNote, RefMan)

AB - We investigate the effect of nonlinearities on the frequency response of a round, incompressible jet. Experiments show that axisymmetric structures dominate the response of forced and unforced jets. In contrast, linear stability and frequency response analyses predict the asymmetric mode (m=1) to be locally more unstable and globally more amplified than the axisymmetric mode (m=0). We perform a weakly nonlinear expansion of the response of the flow to harmonic forcing and derive an asymptotic expression for the sum of this divergent series beyond its limit of validity. This expression compares reasonably well with the nonlinear gain up to forcing amplitudes an order of magnitude greater than the limit of validity of the weakly nonlinear expansion. For equal forcing amplitudes, the asymmetric mode dominates over the axisymmetric mode. This suggests that the projection of environmental forcing onto the individual azimuthal modes plays an important role in the preferred dynamics of round jets.
AU - Qadri,UA
AU - Schmid,PJ
DO - 10.1103/PhysRevFluids.2.043902
PY - 2017///
SN - 2469-990X
TI - Effect of nonlinearities on the frequency response of a round jet
T2 - Physical Review Fluids
UR -
UR -
VL - 2
ER -