We put forth a modular approach for distilling hidden flow physics from discrete and sparse observations. To address functional expressiblity, a key limitation of the black-box machine learning methods, we have exploited the use of symbolic regression as a principle for identifying relations and operators that are related to the underlying processes. This approach combines evolutionary computation with feature engineering to provide a tool for discovering hidden parameterizations embedded in the trajectory of fluid flows in the Eulerian frame of reference. Our approach in this study mainly involves gene expression programming (GEP) and sequential threshold ridge regression (STRidge) algorithms. We demonstrate our results in three different applications: (i) equation discovery, (ii) truncation error analysis, and (iii) hidden physics discovery, for which we include both predicting unknown source terms from a set of sparse observations and discovering subgrid scale closure models. We illustrate that both GEP and STRidge algorithms are able to distill the Smagorinsky model from an array of tailored features in solving the Kraichnan turbulence problem. Our results demonstrate the huge potential of these techniques in complex physics problems, and reveal the importance of feature selection and feature engineering in model discovery approaches.

1.
M. I.
Jordan
and
T. M.
Mitchell
, “
Machine learning: Trends, perspectives, and prospects
,”
Science
349
,
255
260
(
2015
).
2.
V.
Marx
, “
Biology: The big challenges of big data
,”
Nature
498
,
255
260
(
2013
).
3.
F.
Rosenblatt
, “
The perceptron: A probabilistic model for information storage and organization in the brain
,”
Psychol. Rev.
65
,
386
(
1958
).
4.
Y.
LeCun
,
Y.
Bengio
, and
G.
Hinton
, “
Deep learning
,”
Nature
521
,
436
(
2015
).
5.
E. J.
Candes
,
M. B.
Wakin
, and
S. P.
Boyd
, “
Enhancing sparsity by reweighted l1 minimization
,”
J. Fourier Anal. Appl.
14
,
877
905
(
2008
).
6.
E. J.
Candes
and
M. B.
Wakin
, “
An introduction to compressive sampling
,”
IEEE Signal Process. Mag.
25
,
21
30
(
2008
).
7.
J. R.
Koza
,
Genetic Programming: On the Programming of Computers by Means of Natural Selection
(
MIT Press
,
Cambridge, MA, USA
,
1992
), Vol. 1.
8.
C.
Ferreira
, “
Gene expression programming: A new adaptive algorithm for solving problems
,” preprint arXiv:cs/0102027 (
2001
).
9.
C.
Ferreira
,
Gene Expression Programming: Mathematical Modeling by an Artificial Intelligence
(
Springer
,
2006
), Vol. 21.
10.
M.
Mitchell
,
An Introduction to Genetic Algorithms
(
MIT Press
,
1998
).
11.
J. H.
Holland
,
Adaptation in Natural and Artificial Systems, 1975
(
University of Michigan Press
,
Ann Arbor, MI
,
1992
).
12.
M.
Schmidt
and
H.
Lipson
, “
Distilling free-form natural laws from experimental data
,”
Science
324
,
81
85
(
2009
).
13.
J.
Bongard
and
H.
Lipson
, “
Automated reverse engineering of nonlinear dynamical systems
,”
Proc. Natl. Acad. Sci. U. S. A.
104
,
9943
9948
(
2007
).
14.
Y.
Yang
,
C.
Wang
, and
C.
Soh
, “
Force identification of dynamic systems using genetic programming
,”
Int. J. Numer. Methods Eng.
63
,
1288
1312
(
2005
).
15.
L.
Ferariu
and
A.
Patelli
, “
Elite based multiobjective genetic programming for nonlinear system identification
,” in
International Conference on Adaptive and Natural Computing Algorithms
(
Springer
,
2009
), pp.
233
242
.
16.
C.
Luo
,
Z.
Hu
,
S.-L.
Zhang
, and
Z.
Jiang
, “
Adaptive space transformation: An invariant based method for predicting aerodynamic coefficients of hypersonic vehicles
,”
Eng. Appl. Artif. Intell.
46
,
93
103
(
2015
).
17.
S. L.
Brunton
and
B. R.
Noack
, “
Closed-loop turbulence control: Progress and challenges
,”
Appl. Mech. Rev.
67
,
050801
(
2015
).
18.
N.
Gautier
,
J.-L.
Aider
,
T.
Duriez
,
B.
Noack
,
M.
Segond
, and
M.
Abel
, “
Closed-loop separation control using machine learning
,”
J. Fluid Mech.
770
,
442
457
(
2015
).
19.
T.
Duriez
,
V.
Parezanović
,
K.
von Krbek
,
J.-P.
Bonnet
,
L.
Cordier
,
B. R.
Noack
,
M.
Segond
,
M.
Abel
,
N.
Gautier
,
J.-L.
Aider
 et al., “
Feedback control of turbulent shear flows by genetic programming
,” preprint arXiv:1505.01022 (
2015
).
20.
A.
Debien
,
K. A.
Von Krbek
,
N.
Mazellier
,
T.
Duriez
,
L.
Cordier
,
B. R.
Noack
,
M. W.
Abel
, and
A.
Kourta
, “
Closed-loop separation control over a sharp edge ramp using genetic programming
,”
Exp. Fluids
57
,
40
(
2016
).
21.
M.
Quade
,
M.
Abel
,
K.
Shafi
,
R. K.
Niven
, and
B. R.
Noack
, “
Prediction of dynamical systems by symbolic regression
,”
Phys. Rev. E
94
,
012214
(
2016
).
22.
C.
Luo
and
S.-L.
Zhang
, “
Parse-matrix evolution for symbolic regression
,”
Eng. Appl. Artif. Intell.
25
,
1182
1193
(
2012
).
23.
M. F.
Brameier
and
W.
Banzhaf
,
Linear Genetic Programming
(
Springe-Verlag
,
New York
,
2007
).
24.
R. S.
Faradonbeh
and
M.
Monjezi
, “
Prediction and minimization of blast-induced ground vibration using two robust meta-heuristic algorithms
,”
Eng. Comput.
33
,
835
851
(
2017
).
25.
R. S.
Faradonbeh
,
A.
Salimi
,
M.
Monjezi
,
A.
Ebrahimabadi
, and
C.
Moormann
, “
Roadheader performance prediction using genetic programming (GP) and gene expression programming (GEP) techniques
,”
Environ. Earth Sci.
76
,
584
(
2017
).
26.
F. S.
Hoseinian
,
R. S.
Faradonbeh
,
A.
Abdollahzadeh
,
B.
Rezai
, and
S.
Soltani-Mohammadi
, “
Semi-autogenous mill power model development using gene expression programming
,”
Powder Technol.
308
,
61
69
(
2017
).
27.
H.
Çanakc
ı,
A.
Baykasoğlu
, and
H.
Güllü
, “
Prediction of compressive and tensile strength of Gaziantep basalts via neural networks and gene expression programming
,”
Neural Comput. Appl.
18
,
1031
(
2009
).
28.
J.
Weatheritt
and
R.
Sandberg
, “
A novel evolutionary algorithm applied to algebraic modifications of the RANS stress–strain relationship
,”
J. Comput. Phys.
325
,
22
37
(
2016
).
29.
M.
Schoepplein
,
J.
Weatheritt
,
R.
Sandberg
,
M.
Talei
, and
M.
Klein
, “
Application of an evolutionary algorithm to LES modelling of turbulent transport in premixed flames
,”
J. Comput. Phys.
374
,
1166
1179
(
2018
).
30.
J.
Weatheritt
and
R. D.
Sandberg
, “
Hybrid Reynolds-averaged/large-eddy simulation methodology from symbolic regression: Formulation and application
,”
AIAA J.
55
,
3734
3746
(
2017
).
31.
H.
Rauhut
, “
Compressive sensing and structured random matrices
,” in
Theoretical Foundations and Numerical Methods for Sparse Recovery
(
Walter de Gruyter GmbH & Co. KG, Berlin
,
2010
), Vol. 9, pp.
1
92
.
32.
R.
Tibshirani
, “
Regression shrinkage and selection via the LASSO
,”
J. R. Stat. Soc.: Ser. B
58
,
267
288
(
1996
).
33.
G.
James
,
D.
Witten
,
T.
Hastie
, and
R.
Tibshirani
,
An Introduction to Statistical Learning
(
Springer Science+Business Media
,
New York
,
2013
), Vol. 112.
34.
R.
Tibshirani
,
M.
Wainwright
, and
T.
Hastie
,
Statistical Learning with Sparsity: The LASSO and Generalizations
(
Chapman and Hall/CRC
,
Florida, USA
,
2015
).
35.
E. J.
Candes
,
J. K.
Romberg
, and
T.
Tao
, “
Stable signal recovery from incomplete and inaccurate measurements
,”
Commun. Pure Appl. Math.
59
,
1207
1223
(
2006
).
36.
K. P.
Murphy
,
Machine Learning: A Probabilistic Perspective
(
MIT Press
,
Cambridge, MA, USA
,
2012
).
37.
H.
Zou
and
T.
Hastie
, “
Regularization and variable selection via the elastic net
,”
J. R. Stat. Soc.: Ser. B
67
,
301
320
(
2005
).
38.
J.
Friedman
,
T.
Hastie
, and
R.
Tibshirani
, “
Regularization paths for generalized linear models via coordinate descent
,”
J. Stat. Software
33
,
106182
(
2010
).
39.
S. L.
Brunton
,
J. L.
Proctor
, and
J. N.
Kutz
, “
Discovering governing equations from data by sparse identification of nonlinear dynamical systems
,”
Proc. Natl. Acad. Sci. U. S. A.
113
,
3932
3937
(
2016
).
40.
S. H.
Rudy
,
S. L.
Brunton
,
J. L.
Proctor
, and
J. N.
Kutz
, “
Data-driven discovery of partial differential equations
,”
Sci. Adv.
3
,
e1602614
(
2017
).
41.
H.
Schaeffer
,
R.
Caflisch
,
C. D.
Hauck
, and
S.
Osher
, “
Sparse dynamics for partial differential equations
,”
Proc. Natl. Acad. Sci. U. S. A.
110
,
6634
6639
(
2013
).
42.
H.
Schaeffer
, “
Learning partial differential equations via data discovery and sparse optimization
,”
Proc. R. Soc. A
473
,
20160446
(
2017
).
43.
G.
Tran
and
R.
Ward
, “
Exact recovery of chaotic systems from highly corrupted data
,”
Multiscale Model. Simul.
15
,
1108
1129
(
2017
).
44.
H.
Schaeffer
,
G.
Tran
, and
R.
Ward
, “
Extracting sparse high-dimensional dynamics from limited data
,”
SIAM J. Appl. Math.
78
,
3279
3295
(
2018
).
45.
N. M.
Mangan
,
J. N.
Kutz
,
S. L.
Brunton
, and
J. L.
Proctor
, “
Model selection for dynamical systems via sparse regression and information criteria
,”
Proc. R. Soc. A
473
,
20170009
(
2017
).
46.
N. M.
Mangan
,
S. L.
Brunton
,
J. L.
Proctor
, and
J. N.
Kutz
, “
Inferring biological networks by sparse identification of nonlinear dynamics
,”
IEEE Trans. Mol. Biol. Commun. Multi-Scale
2
,
52
63
(
2016
).
47.
J.-C.
Loiseau
,
B. R.
Noack
, and
S. L.
Brunton
, “
Sparse reduced-order modelling: Sensor-based dynamics to full-state estimation
,”
J. Fluid Mech.
844
,
459
490
(
2018
).
48.
M.
Schmelzer
,
R.
Dwight
, and
P.
Cinnella
, “
Data-driven deterministic symbolic regression of nonlinear stress-strain relation for rans turbulence modelling
,” in
2018 Fluid Dynamics Conference
(
AIAA
,
2018
), p.
2900
.
49.
P.
Zheng
,
T.
Askham
,
S. L.
Brunton
,
J. N.
Kutz
, and
A. Y.
Aravkin
, “
A unified framework for sparse relaxed regularized regression: SR3
,”
IEEE Access
7
,
1404
1423
(
2018
).
50.
T.
Zhang
, “
Adaptive forward-backward greedy algorithm for sparse learning with linear models
,” in
Advances in Neural Information Processing Systems
(
NIPS
,
2009
), pp.
1921
1928
.
51.
S.
Thaler
,
L.
Paehler
, and
N. A.
Adams
, “
Sparse identification of truncation errors
,”
J. Comput. Phys.
397
,
108851
(
2019
).
52.
T.
McConaghy
, “
FFX: Fast, scalable, deterministic symbolic regression technology
,” in
Genetic Programming Theory and Practice IX
(
Springer
,
2011
), pp.
235
260
.
53.
H.
Vaddireddy
and
O.
San
, “
Equation discovery using fast function extraction: A deterministic symbolic regression approach
,”
Fluids
4
,
111
(
2019
).
54.
M.
Schmelzer
,
R. P.
Dwight
, and
P.
Cinnella
, “
Machine learning of algebraic stress models using deterministic symbolic regression
,” preprint arXiv:1905.07510 (
2019
).
55.
C.
Chen
,
C.
Luo
, and
Z.
Jiang
, “
Elite bases regression: A real-time algorithm for symbolic regression
,” in
2017 13th International Conference on Natural Computation, Fuzzy Systems and Knowledge Discovery (ICNC-FSKD)
(
IEEE
,
2017
), pp.
529
535
.
56.
T.
Worm
and
K.
Chiu
, “
Prioritized grammar enumeration: Symbolic regression by dynamic programming
,” in
Proceedings of the 15th Annual Conference on Genetic and Evolutionary Computation
(
ACM
,
2013
), pp.
1021
1028
.
57.
D.
Ciregan
,
U.
Meier
, and
J.
Schmidhuber
, “
Multi-column deep neural networks for image classification
,” in
2012 IEEE Conference on Computer Vision and Pattern Recognition
(
IEEE
,
2012
), pp.
3642
3649
.
58.
A.
Karpathy
and
L.
Fei-Fei
, “
Deep visual-semantic alignments for generating image descriptions
,” in
Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition
(
IEEE
,
2015
), pp.
3128
3137
.
59.
A. E.
Sallab
,
M.
Abdou
,
E.
Perot
, and
S.
Yogamani
, “
Deep reinforcement learning framework for autonomous driving
,”
Electron. Imaging
2017
,
70
76
.
60.
M.
Raissi
,
P.
Perdikaris
, and
G. E.
Karniadakis
, “
Physics-informed neural networks: A deep learning framework for solving forward and inverse problems involving nonlinear partial differential equations
,”
J. Comput. Phys.
378
,
686
707
(
2019
).
61.
M.
Raissi
,
P.
Perdikaris
, and
G. E.
Karniadakis
, “
Numerical Gaussian processes for time-dependent and nonlinear partial differential equations
,”
SIAM J. Sci. Comput.
40
,
A172
A198
(
2018
).
62.
M.
Raissi
and
G. E.
Karniadakis
, “
Hidden physics models: Machine learning of nonlinear partial differential equations
,”
J. Comput. Phys.
357
,
125
141
(
2018
).
63.
J.
Kocijan
,
A.
Girard
,
B.
Banko
, and
R.
Murray-Smith
, “
Dynamic systems identification with Gaussian processes
,”
Math. Comput. Modell. Dyn. Syst.
11
,
411
424
(
2005
).
64.
G.
Gregorčič
and
G.
Lightbody
, “
Nonlinear system identification: From multiple-model networks to Gaussian processes
,”
Eng. Appl. Artif. Intell.
21
,
1035
1055
(
2008
).
65.
L.
Cordier
,
B. R.
Noack
,
G.
Tissot
,
G.
Lehnasch
,
J.
Delville
,
M.
Balajewicz
,
G.
Daviller
, and
R. K.
Niven
, “
Identification strategies for model-based control
,”
Exp. Fluids
54
,
1580
(
2013
).
66.
Z.
Wang
,
D.
Xiao
,
F.
Fang
,
R.
Govindan
,
C. C.
Pain
, and
Y.
Guo
, “
Model identification of reduced order fluid dynamics systems using deep learning
,”
Int. J. Numer. Methods Fluids
86
,
255
268
(
2018
).
67.
J.-F.
Cai
,
B.
Dong
,
S.
Osher
, and
Z.
Shen
, “
Image restoration: Total variation, wavelet frames, and beyond
,”
J. Am. Math. Soc.
25
,
1033
1089
(
2012
).
68.
B.
Dong
,
Q.
Jiang
, and
Z.
Shen
, “
Image restoration: Wavelet frame shrinkage, nonlinear evolution PDEs, and beyond
,”
Multiscale Model. Simul.
15
,
606
660
(
2017
).
69.
Z.
Long
,
Y.
Lu
,
X.
Ma
, and
B.
Dong
, “
PDE-net: Learning PDEs from data
,” in
Proceedings of the 35th International Conference on Machine Learning, Proceedings of Machine Learning Research
, edited by
J.
Dy
and
A.
Krause
(
PMLR, Stockholmsmässan
,
Stockholm, Sweden
,
2018
), Vol. 80, pp.
3208
3216
.
70.
Z.
Long
,
Y.
Lu
, and
B.
Dong
, “
PDE-Net 2.0: Learning PDEs from data with a numeric-symbolic hybrid deep network
,”
J. Comput. Phys.
399
,
108925
(
2019
).
71.
C.
Ferreira
, “
Gene expression programming in problem solving
,” in
Soft Computing and Industry
(
Springer
,
2002
), pp.
635
653
.
72.
G.
Shuhua
, geppy: A gene expression programming framework in python,
2019
, https://github.com/ShuhuaGao/geppy.
73.
F.-A.
Fortin
,
F.-M.
De Rainville
,
M.-A.
Gardner
,
M.
Parizeau
, and
C.
Gagné
, “
DEAP: Evolutionary algorithms made easy
,”
J. Mach. Learn. Res.
13
,
2171
2175
(
2012
).
74.
R. G.
Baraniuk
, “
Compressive sensing
,”
IEEE Signal Process. Mag.
24
,
118
124
(
2007
).
75.
H.
Bateman
, “
Some recent researches on the motion of fluids
,”
Mon. Weather Rev.
43
,
163
170
(
1915
).
76.
G. B.
Whitham
,
Linear and Nonlinear Waves
(
John Wiley & Sons
,
2011
), Vol. 42.
77.
M.
Maleewong
and
S.
Sirisup
, “
On-line and off-line POD assisted projective integral for non-linear problems: A case study with Burgers’ equation
,”
Int. J. Math., Comput. Phys., Electr., Comput. Eng.
5
,
984
992
(
2011
).
78.
D. J.
Korteweg
and
G.
de Vries
, “
On the change of form of long waves advancing in a rectangular canal, and on a new type of long stationary waves
,”
Philos. Mag. Series 5
39
(
240
),
422
443
(
1895
)
D. J.
Korteweg
and
G.
de Vries
, [
Philos. Mag.
91
,
1007
1028
(
2011
)].
79.
L.
Wazzan
, “
A modified tanh–coth method for solving the KdV and the KdV–Burgers’ equations
,”
Commun. Nonlinear Sci. Numer. Simul.
14
,
443
450
(
2009
).
80.
T.
Ozis
and
S.
Ozer
, “
A simple similarity-transformation-iterative scheme applied to Korteweg–de Vries equation
,”
Appl. Math. Comput.
173
,
19
32
(
2006
).
81.
G. L.
Lamb
, Jr.
,
Elements of Soliton Theory
(
Wiley-Interscience
,
New York
,
1980
).
82.
T.
Kawahara
, “
Oscillatory solitary waves in dispersive media
,”
J. Phys. Soc. Jpn.
33
,
260
264
(
1972
).
83.
T.
Kawahara
,
N.
Sugimoto
, and
T.
Kakutani
, “
Nonlinear interaction between short and long capillary-gravity waves
,”
J. Phys. Soc. Jpn.
39
,
1379
1386
(
1975
).
84.
J. K.
Hunter
and
J.
Scheurle
, “
Existence of perturbed solitary wave solutions to a model equation for water waves
,”
Physica D
32
,
253
268
(
1988
).
85.
Sirendaoreji
, “
New exact travelling wave solutions for the Kawahara and modified Kawahara equations
,”
Chaos, Solitons Fractals
19
,
147
150
(
2004
).
86.
C.
Zhi-Xiong
and
G.
Ben-Yu
, “
Analytic solutions of the Nagumo equation
,”
IMA J. Appl. Math
48
,
107
115
(
1992
).
87.
J.
Nagumo
,
S.
Arimoto
, and
S.
Yoshizawa
, “
An active pulse transmission line simulating nerve axon
,”
Proc. IRE
50
,
2061
2070
(
1962
).
88.
D. G.
Aronson
and
H. F.
Weinberger
, “
Multidimensional nonlinear diffusion arising in population genetics
,”
Adv. Math.
30
,
33
76
(
1978
).
89.
A.
Scott
, “
Neuristor propagation on a tunnel diode loaded transmission line
,”
Proc. IEEE
51
,
240
(
1963
).
90.
M.
Dehghan
and
F.
Fakhar-Izadi
, “
Pseudospectral methods for Nagumo equation
,”
Int. J. Numer. Methods Biomed. Eng.
27
,
553
561
(
2011
).
91.
A.
Barone
,
F.
Esposito
,
C.
Magee
, and
A.
Scott
, “
Theory and applications of the sine-gordon equation
,”
La Riv. Nuovo Cimento
1
,
227
267
(
1971
).
92.
J.
Perring
and
T.
Skyrme
, “
A model unified field equation
,”
Nucl. Phys.
31
,
550
555
(
1962
).
93.
C. W.
Hirt
, “
Heuristic stability theory for finite-difference equations
,”
J. Comput. Phys.
2
,
339
355
(
1968
).
94.
R. D.
Ritchmyer
and
K.
Norton
,
Difference Methods for Initial Value Problems
(
Jonh Wiley & Sons
,
New York
,
1967
).
95.
G.
Klopfer
and
D. S.
McRae
, “
Nonlinear truncation error analysis of finite difference schemes forthe Euler equations
,”
AIAA J.
21
,
487
494
(
1983
).
96.
A.
Majda
and
S.
Osher
, “
A systematic approach for correcting nonlinear instabilities
,”
Numer. Math.
30
,
429
452
(
1978
).
97.
E.
Ozbenli
and
P.
Vedula
, “
Numerical solution of modified differential equations based on symmetry preservation
,”
Phys. Rev. E
96
,
063304
(
2017
).
98.
E.
Ozbenli
and
P.
Vedula
, “
High order accurate finite difference schemes based on symmetry preservation
,”
J. Comput. Phys.
349
,
376
398
(
2017
).
99.
N.
Adams
,
S.
Hickel
, and
S.
Franz
, “
Implicit subgrid-scale modeling by adaptive deconvolution
,”
J. Comput. Phys.
200
,
412
431
(
2004
).
100.
L. G.
Margolin
and
W. J.
Rider
, “
A rationale for implicit turbulence modelling
,”
Int. J. Numer. Methods Fluids
39
,
821
841
(
2002
).
101.
C.
Hirsch
,
Numerical Computation of Internal and External Flows: The Fundamentals of Computational Fluid Dynamics
(
Elsevier
,
Burlington, MA
,
2007
).
102.
V. M.
Krasnopolsky
and
M. S.
Fox-Rabinovitz
, “
Complex hybrid models combining deterministic and machine learning components for numerical climate modeling and weather prediction
,”
Neural Networks
19
,
122
134
(
2006
).
103.
V. M.
Krasnopolsky
and
M. S.
Fox-Rabinovitz
, “
A new synergetic paradigm in environmental numerical modeling: Hybrid models combining deterministic and machine learning components
,”
Ecol. Modell.
191
,
5
18
(
2006
).
104.
S.
Dhingra
,
R. B.
Madda
,
A. H.
Gandomi
,
R.
Patan
, and
M.
Daneshmand
, “
Internet of things mobile-air pollution monitoring system (IoT-Mobair)
,”
IEEE Internet Things J.
6
,
5577
5584
(
2019
).
105.
N.
Kumar
, “
Unsteady flow against dispersion in finite porous media
,”
J. Hydrol.
63
,
345
358
(
1983
).
106.
J.
Isenberg
and
C.
Gutfinger
, “
Heat transfer to a draining film
,”
Int. J. Heat Mass Transfer
16
,
505
512
(
1973
).
107.
V.
Guvanasen
and
R.
Volker
, “
Numerical solutions for solute transport in unconfined aquifers
,”
Int. J. Numer. Methods Fluids
3
,
103
123
(
1983
).
108.
P.
Meunier
,
S.
Le Dizès
, and
T.
Leweke
, “
Physics of vortex merging
,”
C. R. Phys.
6
,
431
450
(
2005
).
109.
O.
San
and
A. E.
Staples
, “
High-order methods for decaying two-dimensional homogeneous isotropic turbulence
,”
Comput. Fluids
63
,
105
127
(
2012
).
110.
O.
San
and
A. E.
Staples
, “
A coarse-grid projection method for accelerating incompressible flow computations
,”
J. Comput. Phys.
233
,
480
508
(
2013
).
111.
J. N.
Reinaud
and
D. G.
Dritschel
, “
The critical merger distance between two co-rotating quasi-geostrophic vortices
,”
J. Fluid Mech.
522
,
357
381
(
2005
).
112.
A.
Arakawa
, “
Computational design for long-term numerical integration of the equations of fluid motion: Two-dimensional incompressible flow. Part I
,”
J. Comput. Phys.
1
,
119
143
(
1966
).
113.
S.
Pawar
and
O.
San
, “
CFD Julia: A learning module structuring an introductory course on computational fluid dynamics
,”
Fluids
4
,
159
(
2019
).
114.
G.
Boffetta
and
S.
Musacchio
, “
Evidence for the double cascade scenario in two-dimensional turbulence
,”
Phys. Rev. E
82
,
016307
(
2010
).
115.
G.
Boffetta
and
R. E.
Ecke
, “
Two-dimensional turbulence
,”
Annu. Rev. Fluid Mech.
44
,
427
451
(
2012
).
116.
R. H.
Kraichnan
, “
Inertial ranges in two-dimensional turbulence
,”
Phys. Fluids
10
,
1417
1423
(
1967
).
117.
G. K.
Batchelor
, “
Computation of the energy spectrum in homogeneous two-dimensional turbulence
,”
Phys. Fluids
12
,
II
233
(
1969
).
118.
C.
Leith
, “
Atmospheric predictability and two-dimensional turbulence
,”
J. Atmos. Sci.
28
,
145
161
(
1971
).
119.
U.
Piomelli
, “
Large-eddy simulation: Achievements and challenges
,”
Prog. Aerosp. Sci.
35
,
335
362
(
1999
).
120.
C.
Meneveau
and
J.
Katz
, “
Scale-invariance and turbulence models for large-eddy simulation
,”
Annu. Rev. Fluid Mech.
32
,
1
32
(
2000
).
121.
P.
Sagaut
,
Large Eddy Simulation for Incompressible Flows: An Introduction
(
Springer Science & Business Media
,
2006
).
122.
J.
Smagorinsky
, “
General circulation experiments with the primitive equations: I. The basic experiment
,”
Mon. Weather Rev.
91
,
99
164
(
1963
).
123.
C. E.
Leith
, “
Diffusion approximation for two-dimensional turbulence
,”
Phys. Fluids
11
,
671
672
(
1968
).
124.
B.
Baldwin
and
H.
Lomax
, “
Thin-layer approximation and algebraic model for separated turbulentflows
,” in
16th Aerospace Sciences Meeting
(
AIAA
,
1978
), p.
257
.
125.
A.
Smith
and
T.
Cebeci
, “
Numerical solution of the turbulent-boundary-layer equations
,” Technical Report DAC 33735,
DTIC
,
1967
.
126.
R.
Maulik
,
O.
San
,
A.
Rasheed
, and
P.
Vedula
, “
Subgrid modelling for two-dimensional turbulence using neural networks
,”
J. Fluid Mech.
858
,
122
144
(
2019
).
127.
R.
Maulik
,
O.
San
,
A.
Rasheed
, and
P.
Vedula
, “
Data-driven deconvolution for large eddy simulations of Kraichnan turbulence
,”
Phys. Fluids
30
,
125109
(
2018
).
128.
R.
Maulik
,
O.
San
,
J. D.
Jacob
, and
C.
Crick
, “
Sub-grid scale model classification and blending through deep learning
,”
J. Fluid Mech.
870
,
784
812
(
2019
).
You do not currently have access to this content.