Experimental Heat Transfer, Fluid Mechanics and Thermodynamics 1993

956 Pages·1993·173.317 MB·English

by  M.D. Kelleher, R.K. Shah, K.R. Sreenivasan and Y. Joshi (Eds.)

Experimental Heat Transfer,
Fluid Mechanics
and Thermodynamics
1993
Proceedings of the Third World Conference on
Experimental Heat Transfer, Fluid Mechanics and Thermodynamics
Honolulu, Hawaii, USA, 31 October-5 November, 1993
Editors
M.D. Kelleher R.K. Shah
Naval Postgraduate School Harrison Division, GM
Monterey, CA, USA Lockport, NY, USA
K.R. Sreenivasan Y. Joshi
Yale University Naval Postgraduate School
New Haven, CT, USA Monterey, CA, USA
Volume 1
1993
ELSEVIER
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Library of Congress CatalogIng-ln-PublIcatlon Data
rtorld Conference on Experimental Heat Transfer, Fluid Mechanics, and
Thermodynamics (3rd : 1993 : Honolulu, Hawaii)
Experimental heat transfer, fluid mechanics, and thermodynamics
1993 : proceedings of the Third World Conference on Experimental
Heat Transfer, Fluid Mechanics, and Thermodynamics, Honolulu,
Hawaii, USA, 31 October-5 November 1993 / editors, M.D. Kelleher ...
[et al .].
p. cm. — (Elsevier series in thermal and fluid sciences)
Includes bibliographical references and index.
ISBN 0-444-81619-4
1. Fluid mechanics—Congresses. 2. Heat—Transmission-
-Congresses. 3. Thermodynamics—Congresses. I. Kelleher, Matthew
D. II. Title. III. Series.
QC138.W67 1993
621 .402'2—dc20 93-32073
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ISBN: 0 444 81619 4
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V
PREFACE
This Volume contains papers presented at the 3rd World Conference on Experimental Heat
Transfer, Fluid Mechanics and Thermodynamics, held in Honolulu, Hawaii during October 31-
November 5, 1993. Specifically the volume contains the texts of the Plenary Lecture,
Nusselt-Reynolds Prize Lecture, seven Keynote Lectures, 21 Invited Lectures, and 195
Contributed Papers. The number of the papers and the variety of subjects addressed attest to the
continued vitality and vigor of experimental work. The papers cover a broad spectrum from the
experimental investigation of complex fundamental physical phenomena to the study o fpractical
devices and applications.
A decade ago there were those who predicted that large scale computational codes would
go a long way toward eliminating the need for experiments. What has emerged though is the
true nature of the symbiotic relationship between experimental and computational simulation.
Computation can provide the direction for the conduct of efficient experimentation while
experimentation is necessary to verify complex computational codes and for complex situations
for which no reasonably accurate numerical analysis is possible. Also, physical experiments still
possess unsurpassed advantages as a tool for exploring and discovering new physical phenomena.
The papers contained in this volume reflect the ingenuity and originality of experimental
work in the areas of fluid mechanics, heat transfer and thermodynamics. A quick perusal of the
papers also indicates that the quality of work is not limited by geography. The contributors to
the Volume come from 27 countries and provide an indication of how well the worldwide
scientific community is networked.
The two previous Conferences were held m Dubrovnik, Yugoslavia. The first was held in
September 1988, and the second in June 1991. In an effort to reflect the trul yworldwide nature
of the participants of the Conference, the Scientific Committee at the Firs tWorld Conference
in 1988 had decided to move the conference location worldwide after the Second World
conference. Accordingly, the venue has been moved to the USA this time.
An attempt has been made to use a uniform outline and method of presentation of each
paper. The International System of Units (SI) is used throughout the proceedings. All keynote
papers are included first followed by all invited papers. Contributed papers are grouped in
appropriate sections to provide better access to readers. In addition to the Table of Contents at
the beginning of the proceedings, an author index is included at the end of the volume.
We are grateful to the lead scientists of this conference, experts in the area of thermal and
fluid science, for their contributions in coordinating the evaluation of contributed papers and
maintaining the high quality of research papers presented in this proceedings. We especially
acknowledge the professional help of over 700 reviewers from all over the world for selection
of papers and suggestions for improvement of the content of accepted papers published in the
proceedings.
vi
The sponsorship of the following professional societies and institutions also contributed to
the success of the conference:
. American Society of Mechanical Engineers
. American Institute of Chemical Engineers
. National Committee of Heat and Mass Transfer, Russia
. The Society of Chemical Engineers, Japan
. Regional Centre of Energy, Heat and Mass Transfer for
Asia and the Pacific
Finally, we greatly appreciate the cooperation provided by Ms. Inez van der Heide of
Elsevier Science Publishers B.V. for her preparation of this fine proceedings in a very timely
manner.
The Editors
vii
SCIENTIFIC COMMITTEE
Conference Chairman
M.D. Kelleher
Naval Postgraduate School
Monterey, CA, USA
Conference Vice-chairman
K.R. Sreenivasan
Yale University
New Haven, CT, USA
Assistant Program Chairman
Y. Joshi
Naval Postgraduate School
Monterey, CA, USA
Conference Scientific Secretary
R.K. Shah
Harrison Division, GMC
Lockport, NY, USA
Local Organizing Committee Chairman
P. Cheng
Univeristy of Hawaii
Honolulu, Hawaii, USA
LEAD SCIENTISTS
P.J. Catania, International Energy Foundation, Regina, Canada
G.P. Celata, ENEA Casaccia, Roma, Italy
J.C. Chen, Lehigh University, Bethleham, PA, USA
Dr. T. Choi, Korea Institute of Machinery & Metals, Kyungnam, S. Korea
G.R. Cunnington, Jr., Lockheed Missiles & Space Co., Palo Alto, CA, USA
D.S. Dolling, University of Texas at Austin, Austin, TX, USA
L.J. Fang, Industrial Technology Res. Inst., Hsinchu, Taiwan, China
M. Gharib, California Institute of Technology, Pasadena, CA, USA
P.J. Heggs, University of Bradford, Bradford, United Kingdom
L.A. Kennedy, Ohio State University, Columbus, OH, USA
V.V. Klimenko, Moscow Power Engineering Institute, Moscow, Russia
D. G. KrOger, University of Stellenbosch, Stellenbosch, South Africa
M. Lance, Ecole Centrale de Lyon, Ecully, France
A.I. Leontiev, Moscow Higher Technical School, Moscow, Russia
viii
L. Martfti, Institute of Atomic Energy Research, Budapest, Hungary
L.F. Melo, University of Minho, Braga, Portugal
Y. Miyake, Osaka University, Osaka, Japan
A.K. Mohanty,'Indian Institute of Technology, Kharagpur, India
P.H. Oosthuizen, Queen's University, Kingston, Canada
E. Payko$, Middle East Technical University, Ankara, Turkey
A. Pollard, Queen's University, Kingston, Canada
AT. Prata, Universidade Federal de Santa Catarina, Florian6polis, SC, Brazil
K. Rehme, Kernforschungszentrum Karlsruhe GmbH, Karlsruhe, Germany
D.P. Sekuli6, University of Novi Sad, Novi Sad, Yugoslavia
B. Sund6n, Chalmers University of Technology, GOteborg, Sweden
I. Tanasawa, University of Tokyo, Tokyo, Japan
P.R. Viswanath, National Aeronautical Laboratory, Bangalore, India
M.C. Welsh, CSIRO Div. of Building, Construction, and Engineering, Highett, Australia
S.M. Yang, Shanghai Jiaotong University, Sanghai, China
A.A. Zukauskas, Lithuanian Academy of Sciences, Vilnius, Lithuania
ASSEMBLY OF WORLD CONFERENCES
Officers
R.K. Shah, President
Harrison Division, GMC, Lockport, NY, USA
J.F. Keffer, Vice President
University of Toronto, Toronto, Canada
T. Aihara, Member
Tohoku University, Sendai, Japan
J. Bataille, Member
Ecole Centrale de Lyon, Ecully, France
E.N. GaniC, Secretary General
University of Sarajevo, Sarajevo, Bosnia-Herzegovina
General Members
J.S.M. Botterill, UK R. Letan, Israel
P.J. Catania, Canada Y. Miyake, Japan
G.P. Celata, Italy A.K. Mohanty, India
T. Choi, S. Korea W. Nakayama, Japan
M. Cumo, Italy E. Payko?, Turkey
J.E. Fackrell, UK A. Pollard, Canada
L.J. Fang, Taiwan, China A.T. Prata, Brazil
M. Giot, Belgium K. Rehme, Germany
Z.Y. Guo, Beijing, China V.M.K. Sastri, India
M.D. Kelleher, USA K.R. Sreenivasan, USA
V.V. Klimenko, Russia M.C. Welsh, Australia
Y. Kurosaki, Japan K.T. Yang, USA
A. Leontiev, Russia
Experimental Heat Transfer, Fluid Mechanics and Thermodynamics 1993
M.D. Kelleher et al. (Editors)
1993 Elsevier Science Publishers B.V. 3
THE CHANGING ROLES OF EXPERIMENTAL AND COMPUTATIONAL FLUID MECHANICS
AJ. Strazisar
NASA Lewis Research Center, Cleveland, OH 44135 U.S.A.
ABSTRACT
When computational fluid mechanics was in its infancy, the complexity of our experimental, theoretical, and nu­
experiments and theoretical analysis were often the pri­ merical methods - it is a rare individual who is expert in all
mary approaches used to study flow physics. Numeri­ three. The field of fluid and thermal sciences has therefore
cal simulations were performed after an experiment was been divided by natural forces into two "camps", exper­
complete, and the measured, theoretical, and numerical imental and theoretical/analytic/computational. In addi­
results were compared to assess the accuracy of the nu­ tion, the very organization of our research laboratories, in
merical results. As numerical simulation techniques have which there are quite often separate "test" and "numerical
matured, computational, analytic, and experimental efforts analysis" groups, continues to foster this situation. Be­
have become equal partners in fluid mechanics research. cause of these facts, the integration of experimental and
Today numerical simulations are being used to guide the computational approaches in a particular investigation is
design of experimental hardware, to determine those ar­ not something which naturally "happens" - it must be pro-
eas of the flow field in which to concentrate the measure­ actively sought by one camp or the other.
ment effort, and to complement measurements in studying In the past, experimental and analytic approaches to
flow physics. The changing roles of experimental, ana­ problems were often done separately. The interaction be­
lytical, and computational research will be traced by re­ tween the two approaches consisted of comparing results
viewing several investigations in which these approaches when both efforts were complete, and learning from the re­
were used in varying degrees. A case will be made for sults. This "open loop" way of doing business has changed
maintaining a high degree of interaction between these ap­ markedly over the past forty years. I believe that this
proaches throughout the course of an investigation. The change has been driven by the significant advances which
development of prototype computing systems designed to have occurred in both analysis and measurement capa­
enhance the integration of numerical simulations and flow bility. During this time, instrumentation has progressed
physics experiments will also be described. from pitot probes and thermocouples to high-response in­
struments (such as hot-wires and semiconductor pressure
INTRODUCTION transducers) and to non-intrusive optical techniques (such
The importance of using experimental measurements, as laser anemometry and laser-based spectroscopy). Anal­
mathematical analysis, and numerical methods to investi­ ysis approaches have moved from the realm of approxima­
gate fluid mechanics problems has long been recognized. tion methods to the realm of computational fluid mechan­
Most of us are introduced to this concept during our for­ ics, which in itself has moved from the solution of invis-
mal education. Graduate programs of study in fluid and cid equations to the solution of the full three- dimensional
thermal sciences include strong emphasis on pure and ap­ Navier-Stokes equations. These advances now necessitate
plied mathematics and, in more recent times, on numerical a new way of doing business, in which computations and
methods as well. Graduate students who perform an ex­ experiments are conducted concurrently during an inves­
periment for their dissertation research are often encour­ tigation. For example, the experimentalist needs to know
aged by their professors to either perform some analysis "Where should I concentrate my measurements? Is there
of the problem on their own or to compare their mea­ likely to be separated flow in the corner of the model?"
sured results with theoretical, analytic, or computational The analyst can answer "Yes, I predict separation will oc­
results generated by other researchers. Conversely, stu­ cur, but I don't trust my transition model. Can you tell
dents who pursue an analytic approach to a problem are me where the flow separates? My predicted separation
often encouraged to compare their results to experimen­ point varies as I change the parameters in my transition
tal measurements in order to assess the accuracy of their model and I'd like to know which settings yield the best
results. agreement with your measurements".
In our professional careers we tend to specialize in one The roles of analysis and experiments in fluid mechan­
approach or the other. This is in large part necessitated by ics research will be examined by reviewing several differ-
4
ter a close interaction between the three disciplines will
also be described.
BOUNDARY LAYER STABILITY — A STUDY OF
INDEPENDENT INVESTIGATIONS
The first example which I would like to examine con­
sists of several investigations dealing with the stability of
laminar boundary layers to small disturbances. These in­
vestigations were carried out over a period of 40 years by
different research groups. Taken as a whole, they repre­
Understanding of Flow Physics sent what I call an "open loop" type of interaction between
Accurate Predictive Capability
computations, modelling, and experiments in that much of
Figure 1 Schematic model of an integrated approach the work progressed in serial fashion rather than concur­
to fluid mechanics research. rently. Before describing the separate investigations, a
little background information is in order.
It is generally accepted that transition from laminar to
ent investigations in which each approach has been used turbulent flow within a boundary layer occurs in several
in varying degrees. This topic has been discussed by sev­ stages. If the free stream disturbance levels are suffi­
eral previous authors. Dunham [1] and Lakshminarayana ciently small, they will excite the normal modes of the
[2] have recently examined the role of computations in laminar boundary layer, which are often referred to as
fluid mechanics research directed at turbomachinery. At Tollmien-Schlichting (TS) waves. These waves are small-
the 2nd World Conference on Experimental Heat Trans­ amplitude, two-dimensional disturbances whose behavior
fer, Fluid Mechanics and Thermodynamics, Bergles [3] is described by the Orr- Sommerfeld equations [5]. If
discussed the role of experiments in fluid mechanics re­ the TS waves decay, then the boundary layer will remain
search. In a review which addressed both analysis and ex­ laminar and the flow will be "stable". If the TS waves
periments, Horlock [4] has pointed out that there are really grow sufficiently strong (an "unstable" situation), they can
six possible interactions between theoretical (T), computa­ trigger non-linear disturbances which in turn can lead to
tional (C) and experimental (E) research, which he labelled the formation of turbulent spots and eventually to a com­
as the T/C, C/T, T/E, E/T, C/E, and E/C interactions. pletely turbulent flow. Understanding the stability of the
In place of Horlock's "theoretical" category, I would boundary layer as evidenced by the behavior of TS waves
like to introduce the concept of flow physics modelling. is therefore an important component of understanding the
Flow physics models are simplified mathematical repre­ larger phenomena of boundary layer transition.
sentations of real flow physics. These models are tightly The Orr-Sommerfeld equations are derived from the full
coupled to both experimental and computational research. Navier-Stokes equations by making several simplifying
The formulation of such models is often based upon ob­ assumptions (see Schlichting [5]). One of these assump­
servations drawn from experimental measurements. The tions is that a flat plate boundary layer can be modelled
models serve to simplify the computational approach to as a parallel flow, i.e. that the streamwise velocity, U, is
a particular problem because the flow physics which they only a function of the distance normal to the plate, y, and
account for does not have to be solved computationally. is independent of the streamwise distance, x. This is ob­
A classic example of flow physics modelling is the tur­ viously a good model when the length Reynolds number
bulence modelling approach used in the solution of the is large and the boundary layer is relatively thin, which
Reynolds-averaged Navier-Stokes equations, wherein tur­ is often the case.
bulent mixing is modelled as a simple diffusion process. Analytic solutions of the Orr-Sommerfeld equations
I believe that a modern approach to research in the fluid were first achieved by Tollmien [6] and Schlichting [7]
and thermal sciences should be structured as shown in Fig­ in the early 1930's. In 1940, a key experiment was per­
ure 1. The key feature of such an approach is the close formed in a flat plate boundary layer in air by Schubauer
interaction between experimental, analytic, and modelling and Skramstad [8]. This team had designed and built a
disciplines. The benefits which can be realized from such wind tunnel with very low turbulence intensity (0.02%)
an approach will be demonstrated by reviewing several re­ in order to study boundary layer transition. The low
search efforts in which the degree of coupling between the free-stream disturbance environment in this tunnel enabled
three disciplines varied. In reviewing these examples, a them to detect TS waves which were triggered by free-
case will be made for the fact that modern fluid mechanics stream disturbances. This discovery was accomplished
research can reap substantial benefits from a strong inter­ using hot wire anemometers to measure the unsteady ve­
action between analysis, computations, and experiments. locity within the boundary layer. In order to more easily
The design of two prototype computer systems which fos­ study the TS waves, Schubauer and Skramstad then added
5
420 1- low Reynolds numbers, they do bracket the experimental
data. In addition, Schubauer and Skramstad noted that the
Data, Schubauer& unstable disturbances which they found at low Reynolds
Skramstad numbers and high frequencies were extremely weak and
difficult to measure, which lead to larger experimental un­
300 4- certainty in the (Re, F) coordinates of the neutral points in
this region in Figure 2. Based on the agreement between
Tollmlen
6 measured and predicted results for several other charac­
Fx io 4-
teristics of the disturbances, Schlichting himself declared
Schlichting in his textbook that "The experimental results show such
180 4- complete agreement with the theory of stability of lami­
nar flows that the latter may now be regarded as a verified
Stable component of fluid mechanics" [5].
During the 1950's and 1960's the solution of the Orr-
Sommerfeld equations was further pursued using ana­
60 4- lytic approaches and, with the aid of computers, finite-
Stable
difference techniques as well. These solutions were dis­
cussed by Jordinson [9], who also solved the equations
»
4A 0n0 ^ 800 1200 numerically on a computer. The maximum unstable fre­
quencies and the lowest Reynolds number for which the
boundary layer is unstable, (termed the minimum critical
Figure 2 Comparison of analytically predicted boundary
Reynolds number, Remc) are summarized in Table 1 for a
layer neutral stability characteristics [6,7] to
number of these investigations. Since the numerical solu­
measured neutral stability characteristics [8].
tions obtained by several additional investigators all gave
exactly the same results, there was a general feeling that
a thin vibrating ribbon placed near the plate surface to in­
the numerical solutions were more accurate than the ear­
troduce small- amplitude two-dimensional harmonic dis­
lier analytic solutions of the Orr-Sommerfeld equation.
turbances into the boundary layer at known frequencies.
They then mapped the growth and decay of these distur­ Table 1 Comparison of measured and predicted
bances as they moved downstream and thus experimen­ properties of the neutral stability curve at
tally established the stability characteristics of the laminar
low Reynolds number.
boundary layer. Figure 2 is a comparison of their exper­
imental results with the calculations of Schlichting and Source Approach FnuuXW6
Tollmien. This figure is called a neutral stability diagram. Tollmein, 1931 Analytic 420 <300
The ordinate is the non-dimensional frequency of the dis­
Schlichting 1933 Analytic 575 178
turbance and the abscissa is the displacement thickness
Reynolds number. The solid lines in Figure 2 are the an­ Lin, 1945 Analytic 425 345
alytical solutions, while the broken lines are curves fared Shen, 1954 Analytic 425 345
through the neutral points measured by Schubauer and Wazzan, 1968 Numerical 520 245
Skramstad. The data points and analytical results define
Jordinson, 1970 Numerical 520 245
the neutral points of the boundary layer, which are the loci
of disturbances that neither grow nor decay. The boundary Schubauer 1940 Exp 400 400
layer is stable to disturbances which fall outside the neu­
tral curve (in other words these disturbances will decay). Jordinson was one of a team of researchers at the Uni­
The boundary layer is unstable to disturbances which fall versity of Edinburgh who were performing an integrated
inside the neutral curve - these disturbances will grow and experimental and computational investigation into why the
are therefore potentially dangerous in that they can lead computed and measured stability characteristics were dif­
to transition. ferent at low Reynolds numbers. In another phase of the
The agreement between experiment and theory shown computational effort, Barry and Ross [10] added terms
in Figure 2 was taken to be quite good by Schubauer to the Orr-Sommerfeld equation which accounted for the
and Skramstad. The agreement between theory and ex­ growth of boundary layer thickness with streamwise dis­
periment at frequencies below 180 is clear. Although tance and used a modified version of Jordinson's program
the analytic solutions do not agree with one another at to numerically solve the equations. In so doing, they
low Reynolds numbers, they do bracket the experimental hoped to determine if the parallel flow assumption was
data. In addition, Schubauer and Skramstad noted that the invalid at low Reynolds numbers and thus the cause of the
6
420
• SchEuxbpaeureirm &e Snktsr amstad • F = 86xl06
A Ross et al
T Wortmann 24
Strazisar et al Non-parallel
* Kachanov et al prediction X.
300 + Non-parallel flow
prediction ^-Parallel
prediction
b • Parallel flow
FxlO | prediction
600 1000
Re 1 4 00
180 +
Figure 4 Comparison of measured and calculated growth
of a disturbance of frequency F=86xl0~~6 as a
function of streamwise distance [13].
alytic solution of the governing equations tractable, was
60 +
too restrictive at low Reynolds numbers. In retrospect,
the earlier attempt to include non-parallel effects made by
Barry and Ross had failed because they had included only
400 800 1200 some of the non-parallel effects.
Re The results shown in Figure 3 might lead one to con­
clude that non-parallel effects are only significant at low
Figure 3 Comparison of measured boundary layer Reynolds number and high frequency, since the parallel
neutral stability points to the neutral stability and non-parallel neutral curves are quite similar for dis­
curves determined using parallel and turbance frequencies less than F=120xl0~6. Further ev­
non-parallel flow calculations [13]. idence that the non-parallel effects are important even at
higher Reynolds numbers can be seen in Figure 4, which
observed discrepancy. In the experimental effort, Ross et compares the predicted and measured log of the distur­
al. [11] repeated Schubauer and Skramstad's experiment. bance amplitude for a frequency of F=86 xlO"6 as a
The numerical results displayed only a slight difference function of streamwise distance (expressed as the displace­
when the non-parallel effects were included — Remc was ment thickness Reynolds number). Note that the results
7
reduced from 520 to 500 and Z ,^ increased from 245 to in Figure 4 represent a cross-sectional cut through Figure
260x10^. On the other hand, the experimental results 3 along a horizontal line at F=86 xlO"6.
were in complete agreement with those of Schubauer and This example is representative of the way in which
Skramstad. At this point, the cause of the experimental much or our fluid mechanics research is conducted. It rep­
and numerical discrepancies was still unresolved. resents a sound investigative approach in which analytic
In the early 1970's, several additional, independent ex­ and experimental investigations were conducted by inde­
perimental and numerical efforts followed. Each new ex­ pendent groups. Researchers learned from one another
perimental investigation verified the fact that the minimum over time and achieved progress toward the ultimate goal
critical Reynolds number for a flat plate laminar bound­ of gaining insight into a particular aspect of fluid physics.
ary layer is Remc= 400. This body of evidence spurred The experimental measurements, which were conducted
continuing efforts to understand this phenomena from a in the actual non-parallel flow, ultimately showed that the
theoretical point of view. Significant progress was finally attempt to "model" the boundary layer as a parallel flow
achieved by Saric and Nayfeh [12,13] who included all was too restrictive. This fact was not immediately obvious
of the non-parallel flow terms in the governing equations for two reasons. First, the measurements departed from
and then solved the equations using the method of multiple parallel-flow predictions in a region in which the mea­
scales. Their analytic results with the non-parallel terms surements were difficult to acquire. There was therefore a
included and neglected are compared to the experimen­ lack of confidence in the early measurements which only
tal results from five independent investigations in Figure disappeared when the measurements were verified during
3. When all non-parallel effects are included, the calcu­ follow-on independent investigations. Second, the early
lated minimum critical Reynolds number is 400. From parallel-flow computational results were misleading be­
this comparison it is evident that the parallel-flow model, cause they agreed closely with one another, which was
adopted almost forty years earlier in order to make the an- taken as a confirmation of the parallel-flow theory, when