Closure Modeling for Three-dimensional Integral Boundary Layer using Physics-constrained Neural Network and Model Inversion

Abstract This paper describes the development of a finite difference method that solves the boundary-layer equations for three-dimensional compressible turbulent flows. The most prominent achievements are the employment of a Newton technique for the simultaneous solution of all governing equations, an option to choose an algebraic or a k-ε eddy-viscosity turbulence model, and the flexible use of curvilinear coordinates. The method is validated by comparisons with a number of experimental and theoretical data sets of three-dimensional, compressible and incompressible, steady and unsteady boundary layers. In parallel, the performance of a three-dimensional compressible industrial integral boundary-layer technique is evaluated by comparisons with experimental test cases and with the results of the field method.

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Study of the Boundary Layer on Ship Forms

Journal of Ship Research ◽

10.5957/jsr.1970.14.3.153 ◽

1970 ◽

Vol 14 (03) ◽

pp. 153-167

Author(s):

W. C. Webster ◽

T.T. Huang

Keyword(s):

Boundary Layer ◽

Shape Factor ◽

Three Dimensional ◽

Momentum Thickness ◽

Flow Conditions ◽

Integral Boundary ◽

Outer Flow ◽

Boundary Layer Equations ◽

Pressure Distributions ◽

Layer Flow

This paper presents a theoretical investigation of the development of the boundary layer about a ship. The "outer flow" conditions, including the streamlines and pressure distributions, are found from linearized, thin-ship theory using the method of Guilloton. Linearized, integral boundary-layer equations appropriate for three-dimensional turbulent flow are integrated numerically along the streamlines to determine the momentum thickness, the shape factor, and the angle of the boundary-layer flow to the outer flow. The results of computations for Series 60, block 0.60 and 0.80 are presented for various Froude numbers and ship lengths.

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Long-Wave and Integral Boundary Layer Analysis of Falling Film Flow on Walls With Three-Dimensional Periodic Structures

ASME 2009 7th International Conference on Nanochannels, Microchannels and Minichannels ◽

10.1115/icnmm2009-82115 ◽

2009 ◽

Author(s):

Tatiana Gambaryan-Roisman ◽

Hongyi Yu ◽

Karsten Lo¨ffler ◽

Peter Stephan

Keyword(s):

Boundary Layer ◽

Reynolds Number ◽

Inclination Angle ◽

Film Flow ◽

Three Dimensional ◽

Falling Film ◽

Integral Boundary ◽

Long Wave ◽

Surface Patterns ◽

Periodic Microstructures

Falling films exhibit very complex wavy patterns, which depend on the properties of the liquid, the Reynolds number, the wall inclination angle, and the distance from the film inlet. The film hydrodynamics and the surface patterns have a high impact on heat and mass transfer. Our aim is to control and enhance heat and mass transport by using walls with specific micro topographies that influence the falling film flow, stability and wavy pattern. In the present work long-wave theory and integral boundary layer (IBL) approximation are used for modelling the falling film flow on walls with three-dimensional periodic microstructures. The wall topography is periodic both in the main flow direction and in the transverse direction. Examples of such microstructures are longitudinal grooves with sinusoidal path (or meandering grooves) and herringbone structures. The effects of the Reynolds number, the wall inclination angle and the longitudinal and transverse periods of the structure on the shape of liquid-gas interface are investigated. It is shown that, as opposed to straight grooves in longitudinal direction, grooves with meandering path may lead to significant interface deformations.

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Stability of a temporally evolving natural convection boundary layer on an isothermal wall

Journal of Fluid Mechanics ◽

10.1017/jfm.2019.639 ◽

2019 ◽

Vol 877 ◽

pp. 1163-1185 ◽

Cited By ~ 2

Author(s):

Junhao Ke ◽

N. Williamson ◽

S. W. Armfield ◽

G. D. McBain ◽

S. E. Norris

Keyword(s):

Boundary Layer ◽

Natural Convection ◽

Linear Stability ◽

Transition Point ◽

Three Dimensional ◽

Base Flow ◽

Convection Boundary Layer ◽

Two Dimensional ◽

Integral Boundary ◽

Convection Boundary

The stability properties of a natural convection boundary layer adjacent to an isothermally heated vertical wall, with Prandtl number 0.71, are numerically investigated in the configuration of a temporally evolving parallel flow. The instantaneous linear stability of the flow is first investigated by solving the eigenvalue problem with a quasi-steady assumption, whereby the unsteady base flow is frozen in time. Temporal responses of the discrete perturbation modes are numerically obtained by solving the two-dimensional linearized disturbance equations using a ‘frozen’ base flow as an initial-value problem at various $Gr_{\unicode[STIX]{x1D6FF}}$, where $Gr_{\unicode[STIX]{x1D6FF}}$ is the Grashof number based on the velocity integral boundary layer thickness $\unicode[STIX]{x1D6FF}$. The resultant amplification rates of the discrete modes are compared with the quasi-steady eigenvalue analysis, and both two-dimensional and three-dimensional direct numerical simulations (DNS) of the temporally evolving flow. The amplification rate predicted by the linear theory compares well with the result of direct numerical simulation up to a transition point. The extent of the linear regime where the perturbations linearly interact with the base flow is thus identified. The value of the transition $Gr_{\unicode[STIX]{x1D6FF}}$, according to the three-dimensional DNS results, is dependent on the initial perturbation amplitude. Beyond the transition point, the DNS results diverge from the linear stability predictions as nonlinear mechanisms become important.

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Experimental Investigation of the Three-Dimensional Flow in an Annular Compressor Cascade

Journal of Turbomachinery ◽

10.1115/1.3262220 ◽

1988 ◽

Vol 110 (4) ◽

pp. 467-478 ◽

Cited By ~ 46

Author(s):

H. D. Schulz ◽

H. D. Gallus

Keyword(s):

Boundary Layer ◽

Experimental Investigation ◽

Three Dimensional ◽

Suction Side ◽

Boundary Layer Transition ◽

Compressor Cascade ◽

Three Dimensional Flow ◽

Layer Transition ◽

Integral Boundary ◽

Dimensional Flow

A detailed experimental investigation was carried out to examine the influence of blade loading on the three-dimensional flow in an annular compressor cascade. Data were acquired over a range of incidence angles. Included are airfoil and endwall flow visualization, measurement of the static pressure distribution on the flow passage surfaces, and radial-circumferential traverse measurements. The data indicate the formation of a strong vortex near the rear of the blade passage. This vortex transports low-momentum fluid close to the hub toward the blade suction side and seems to be partly responsible for the occurrence of a hub corner stall. The effect of increased loading on the growth of the hub corner stall and its impact on the passage blockage are discussed. Detailed mapping of the blade boundary layer was done to determine the loci of boundary layer transition and flow separation. The data have been compared with results from an integral boundary layer method.

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