## References

van den Berg, T. H., Doering, Ch. R., Lohse, D. & Lathrop, D. P.
2003
Smooth and rough boundaries in turbulent Taylor–Couette flow. Phys. Rev. E
68, 036307.

Van den Berg, T. H., van Gils, D. P. M., Lathrop, D. P. & Lohse, D.
2007
Bubbly turbulent drag reduction is a boundary layer effect. Phys. Rev. Lett.
98, 084501.

van den Berg, T. H., Luther, S., Lathrop, D. P. & Lohse, D.
2005
Drag reduction in bubbly Taylor–Couette turbulence. Phys. Rev. Lett.
94, 044501.

Cadot, O., Couder, Y., Daerr, A., Douady, S. & Tsinober, A.
1997
Energy injection in closed turbulent flows: stirring through boundary layers versus inertial stirring. Phys. Rev. E
56, 427–433.

Ceccio, S. L.
2010
Friction drag reduction of external flows with bubble and gas injection. Annu. Rev. Fluid Mech.
42, 183–203.

Chouippe, A., Climent, E., Legendre, D. & Gabillet, C.
2014
Numerical simulation of bubble dispersion in turbulent Taylor–Couette flow. Phys. Fluids
26 (4), 043304.

Deutsch, S., Moeny, M., Fontaine, A. A. & Petrie, H.
2004
Microbubble drag reduction in rough walled turbulent boundary layers with comparison against polymer drag reduction. Exp. Fluids
37, 731–744.

Eckhardt, B., Grossmann, S. & Lohse, D.
2007
Torque scaling in turbulent Taylor–Couette flow between independently rotating cylinders. J. Fluid Mech.
581, 221–250.

Elbing, B. R., Mäkiharju, S., Wiggins, A., Perlin, M., Dowling, D. R. & Ceccio, S. L.
2013
On the scaling of air layer drag reduction. J. Fluid Mech.
717, 484–513.

Elbing, B. R., Winkel, E. S., Lay, K. A., Ceccio, S. L., Dowling, D. R. & Perlin, M.
2008
Bubble-induced skin-friction drag reduction and the abrupt transition to air-layer drag reduction. J. Fluid Mech.
612, 201–236.

Fardin, M. A., Perge, C. & Taberlet, N.
2014
‘The hydrogen atom of fluid dynamics’: introduction to the Taylor–Couette flow for soft matter scientists. Soft Matt.
10, 3523.

Flack, K. A. & Schultz, M. P.
2014
Roughness effects on wall-bounded turbulent flows. Phys. Fluids
26 (10), 101305.

Foeth, E. J.
2008
Decreasing frictional resistance by air lubrication. In 20th Int. HISWA Symp. on Yacht Design and Yacht Construction. HISWA.

van Gils, D. P. M., Bruggert, G. W., Lathrop, D. P., Sun, C. & Lohse, D.
2011a
The Twente turbulent Taylor–Couette (T^{3}C) facility: strongly turbulent (multi-phase) flow between independently rotating cylinders. Rev. Sci. Instrum.
82, 025105.

van Gils, D. P. M., Huisman, S. G., Bruggert, G. W., Sun, C. & Lohse, D.
2011b
Torque scaling in turbulent Taylor–Couette flow with co- and counter-rotating cylinders. Phys. Rev. Lett.
106, 024502.

van Gils, D. P. M., Huisman, S. G., Grossmann, S., Sun, C. & Lohse, D.
2012
Optimal Taylor–Couette turbulence. J. Fluid Mech.
706, 118–149.

van Gils, D. P. M., Narezo Guzman, D., Sun, C. & Lohse, D.
2013
The importance of bubble deformability for strong drag reduction in bubbly turbulent Taylor–Couette flow. J. Fluid Mech.
722, 317–347.

Grossmann, S., Lohse, D. & Sun, C.
2016
High Reynolds number Taylor–Couette turbulence. Annu. Rev. Fluid Mech.
48, 53.

Huisman, S. G., van der Veen, R. C. A., Sun, C. & Lohse, D.
2014
Multiple states in highly turbulent Taylor–Couette flow. Nat. Commun.
5, 3820.

Kodama, Y., Kakugawa, A., Takahashi, T. & Kawashima, H.
2000
Experimental studies on microbubbles and their applicability to ships for skin friction reduction. Intl J. Heat Fluid Flow
21, 582–588.

Kraichnan, R. H.
1962
Turbulent thermal convection at arbritrary Prandtl number. Phys. Fluids
5, 1374.

Lathrop, D. P., Fineberg, J. & Swinney, H. S.
1992a
Transition to shear-driven turbulence in Couette–Taylor flow. Phys. Rev. A
46, 6390–6405.

Lathrop, D. P., Fineberg, J. & Swinney, H. S.
1992b
Turbulent flow between concentric rotating cylinders at large Reynolds numbers. Phys. Rev. Lett.
68, 1515–1518.

Lewis, G. S. & Swinney, H. L.
1999
Velocity structure functions, scaling, and transitions in high-Reynolds-number Couette–Taylor flow. Phys. Rev. E
59, 5457–5467.

Mäkiharju, S., Perlin, M. & Ceccio, S. L.
2012
On the energy economics of air lubrication drag reduction. Intl. J. Nav. Archit. Ocean Engng.
4, 412–422.

Marusic, I., McKeon, B. J., Monkewitz, P. A., Nagib, H. M., Smits, A. J. & Sreenivasan, K. R.
2010
Wall-bounded turbulent flows at high Reynolds numbers: recent advances and key issues. Phys. Fluids
22 (6), 065103.

Murai, Y.
2014
Frictional drag reduction by bubble injection. Exp. Fluids
55 (7), 1773.

Ostilla-Mónico, R., van der Poel, E. P., Verzicco, R., Grossmann, S. & Lohse, D.
2014
Exploring the phase diagram of fully turbulent Taylor–Couette flow. J. Fluid Mech.
761, 1–26.

Rosenberg, B. J., van Buren, T., Matthew, K. F. & Smits, A. J.
2016
Turbulent drag reduction over air- and liquid-impregnated surfaces. Phys. Fluids
28, 015103.

Saranadhi, D., Chen, D., Kleingartner, J. A., Srinivasan, S., Cohen, R. B. & McKinley, G. H.
2016
Sustained drag reduction in a turbulent flow using a low temperature Leidenfrost surface. Sci. Adv.
2 (10), E1600686.

Schultz, M. P.
2007
Effects of coating roughness and biofouling on ship resistance and powering. Biofouling
23 (5), 331–341.

Schultz, M. P., Bendick, J. A., Holm, E. R. & Hertel, W. M.
2011
Economic impact of biofouling on a naval surface ship. Biofouling
27 (1), 87–98.

Shen, X., Perlin, M. & Ceccio, S. L.
2006
Influence of bubble size on micro-bubble drag reduction. Exp. Fluids
41, 415–424.

Spandan, V., Verzicco, R. & Lohse, D.
2017
Deformable ellipsoidal bubbles in Taylor–Couette flow with enhanced Euler–Lagrangian tracking. Phys. Rev. Fluids
2, 104304.

Srinivasan, S., Kleingartner, J. A., Gilbert, J. B., Cohen, R. B., Milne, A. J. B. & McKinley, G. H.
2015
Sustainable drag reduction in turbulent Taylor–Couette flows by depositing sprayable superhydrophobic surfaces. Phys. Rev. Lett.
114, 014501.

Sugiyama, K., Calzavarini, E. & Lohse, D.
2008
Microbubble drag reduction in Taylor–Couette flow in the wavy vortex regime. J. Fluid Mech.
608, 21–41.

Takagi, S. & Matsumoto, Y.
2011
Surfactant effects on bubble motion and bubbly flows. Annu. Rev. Fluid Mech.
43 (1), 615–636.

Takagi, S., Ogasawara, T. & Matsumoto, Y.
2008
The effects of surfactant on the multiscale structure of bubbly flows. Phil. Trans. A. Math. Phys. Engng Sci.
366 (1873), 2117–2129.

Takahashi, T., Kakugawa, A., Nagaya, S., Yanagihara, T. & Kodama, Y.
2001
Mechanisms and scale effects of skin friction reduction by microbubbles. In Proceedings of 2nd Symposium on Smart Control of Turbulence, University of Tokyo.

Toppaladoddi, S., Succi, S. & Wettlaufer, J. S.
2017
Roughness as a route to the ultimate regime of thermal convection. Phys. Rev. Lett.
118, 074503.

van der Veen, R. C. A., Huisman, S. G., Dung, O.-Y., Tang, H.-L., Sun, C. & Lohse, D.
2016
Exploring the phase space of multiple states in highly turbulent Taylor–Couette flow. Phys. Rev. Fluids
1, 024401.

Verschoof, R. A., Bakhuis, D., Bullee, P. A., Huisman, S. G., Sun, C. & Lohse, D.
2018
Air cavities at the inner cylinder of turbulent Taylor–Couette flow. Intl J. Multiphase Flow
105, 264–273.

Verschoof, R. A., van der Veen, R. C. A., Sun, C. & Lohse, D.
2016
Bubble drag reduction requires large bubbles. Phys. Rev. Lett.
117, 104502.

Winkel, E. S., Ceccio, S. L., Dowling, D. R. & Perlin, M.
2004
Bubble-size distributions produced by wall injection of air into flowing freshwater, saltwater and surfactant solutions. Exp. Fluids
37, 802–810.

Zhu, X., Ostilla-Monico, R., Verzicco, R. & Lohse, D.
2016
Direct numerical simulation of Taylor–Couette flow with grooved walls: torque scaling and flow structure. J. Fluid Mech.
794, 746–774.

Zhu, X., Verschoof, R. A., Bakhuis, D., Huisman, S. G., Verzicco, R., Sun, C. & Lohse, D.
2018
Wall roughness induces asymptotic ultimate turbulence. Nat. Phys.
14, 417–423.

Zverkhovskyi, O.2014 Ship drag reduction by air cavities. PhD thesis, Delft University of Technology, Delft, NL.