In the present study, we introduce a method which we call the glass box optimization (GBO) method as a strategy how to reduce flow losses whenever numerical data based on computational fluid dynamics (CFD)-results are available. Based on local values of the velocity and entropy generation fields, a systematic analysis of the loss mechanisms involved is used in order to develop control mechanisms for the reduction of losses due to a conduit component. Furthermore, it is shown how the losses are distributed between a component itself and the adjacent flow field. Since often a large amount of the losses occurs outside of the actual component, it is discussed under which circumstances an optimized component leads to improved efficiency of an entire fluid flow network. The method is exemplified for turbulent flow through a 90 deg bend.

References

References
1.
Munson
,
B.
,
Young
,
D.
, and
Okiishi
,
T.
,
2005
,
Fundamentals of Fluid Mechanics
,
5th ed.
,
Wiley
,
New York
.
2.
Schmandt
,
B.
, and
Herwig
,
H.
,
2011
, “
Internal Flow Losses: A Fresh Look at Old Concepts
,”
ASME J. Fluids Eng.
,
133
(
5
), p.
051201
.
3.
Herwig
,
H.
, and
Schmandt
,
B.
,
2014
, “
How to Determine Losses in a Flow Field: A Paradigm Shift Towards the Second Law Analysis
,”
Entropy
,
16
(
6
), pp.
2959
2989
.
4.
Verstraete
,
T.
,
Coletti
,
F.
,
Bulle
,
J.
,
Van der Wielen
,
T.
, and
Arts
,
T.
,
2013
, “
Optimization of a U-Bend for Minimal Pressure Loss in Internal Cooling Channels—Part I: Numerical Method
,”
ASME J. Turbomach.
,
135
(
5
), p.
051015
.
5.
Herwig
,
H.
, and
Kautz
,
C.
,
2007
,
Technische Thermodynamik
,
Pearson Studium
,
München, Germany
.
6.
Bejan
,
A.
,
1996
,
Entropy Generation Minimization
,
CRC Press
,
Boca Raton
.
7.
Herwig
,
H.
, and
Wenterodt
,
T.
,
2011
,
Entropie für Ingenieure: Erfolgreich das Entropie-Konzept bei energietechnischen Fragestellungen anwenden
,
Vieweg + Teubner Praxis, Grundlagen Maschinenbau
,
Vieweg+Teubner Verlag, Wiesbaden
.
8.
Kock
,
F.
, and
Herwig
,
H.
,
2004
, “
Local Entropy Production in Turbulent Shear Flows: A High Reynolds Number Model With Wall Functions
,”
Int. J. Heat Mass Transfer
,
47
(
10–11
), pp.
2205
2215
.
9.
Kelly
,
S.
,
Tsatsaronis
,
G.
, and
Morosuk
,
T.
,
2009
, “
Advanced Exergetic Analysis: Approaches for Splitting the Exergy Destruction Into Endogenous and Exogenous Parts
,”
Energy
,
34
(
3
), pp.
384
391
.
10.
Gielen
,
R.
,
Van Oevelen
,
T.
, and
Baelmans
,
M.
,
2014
, “
Challenges Associated With Second Law Design in Engineering
,”
Int. J. Energy Res.
,
38
(
12
), pp.
1501
1512
.
11.
Schmandt
,
B.
, and
Herwig
,
H.
,
2011
, “
Loss Coefficients in Laminar Flows: Essential for the Design of Micro Flow Systems
,”
PAMM
,
11
(
1
), pp.
27
30
.
12.
Küppers
,
U.
,
2007
, “
Kleine Biegung, große Wirkung-Bionische Rohrbögen in Lüftungsleitungen
,”
Chemietechnik
,
9
, pp.
24
26
.
13.
Miller
,
D. S.
,
1978
(reprint 1990),
Internal Flow Systems
,
2nd ed.
,
BHRA
,
Cranfield
.
14.
Ito
,
H.
,
1960
, “
Pressure Losses in Smooth Pipe Bends
,”
ASME J. Basic Eng., Ser. D
,
82
(
1
), pp.
131
143
.
15.
Hofmann
,
A.
,
1929
, “
Der Verlust in 90 deg-Rohrkrümmern mit gleichbleibendem Kreisquerschnitt
,”
Mitt. des Hydraul. Instituts der TH München
,
3
, pp.
45
67
.
16.
Idelchik
,
I.
,
2007
,
Handbook of Hydraulic Resistance
,
Begell House
,
Redding, CA
.
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