SINDA/FLUINT Sample Problem Appendix

274 Pages·2015·1.89 MB·English

®
User’s
Sample Problem Appendix Manual May 2015
SINDA/FLUINT
General Purpose Thermal/Fluid
Network Analyzer
Version 5.8
<intentionally blank for 2-sided printing>
TABLE OF CONTENTS
SINDA
SINDA SAMPLE PROBLEM: SATELLITE DEPLOYMENT. . . . . . . . . . . . . . S-1
S.1 Problem Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-1
S.2 A SINDA Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-2
S.3 Preparation for Reduced Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-5
S.4 The Input File (First Run: Orbital Analysis). . . . . . . . . . . . . . . . . . . . . . . . . . S-5
S.5 Output Description (First Run: Orbital Analysis). . . . . . . . . . . . . . . . . . . . . . S-9
S.6 Reduced Model and Parametric Variations. . . . . . . . . . . . . . . . . . . . . . . . . S-10
S.7 A Message to the Novice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-11
Input File: First Run (Orbital Analysis). . . . . . . . . . . . . . . . . . . . . . . . . S-13
Input File: Second Run (Parametric using a Simplified Model). . . . . . S-20
Processor Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-23
FLUINT
PROBLEM A: FILLING TOY BALLOONS . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
A.1 Problem Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
A.2 A FLUINT Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
A.3 The Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3
A.4 Output Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-5
Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-6
Processor Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-9
i
PROBLEM B: SIPHON IN A ROMAN AQUEDUCT . . . . . . . . . . . . . . . . . . . . B-1
B.1 Problem Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
B.2 A FLUINT Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-3
B.3 The Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-5
B.4 Output Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-9
Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-13
Processor Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-24
PROBLEM C: PRESSURE COOKER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
C.1 Problem Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
C.2 A FLUINT Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2
C.3 The Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-3
C.4 Output Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-5
C.5 Alternate Valve Models. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-7
Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-9
Processor Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-13
PROBLEM D: AQUARIUM FILTER AND AERATOR . . . . . . . . . . . . . . . . . . . D-1
D.1 Problem Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1
D.2 A FLUINT Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-3
D.3 The Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-6
D.4 Output Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-9
D.5 Alternate Model: Dissolved Gas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-11
Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-13
Processor Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-18
ii
PROBLEM E: CAPILLARY PUMPED LOOP START-UP. . . . . . . . . . . . . . . . E-1
E.1 Problem Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-2
E.2 A SINDA/FLUINT Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-5
E.3 The Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-11
E.4 Output Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-15
E.5 A Simplified Model for Comparison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-18
Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-20
Processor Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-39
PROBLEM E VARIATION: CORRELATION TO TEST DATA . . . . . . . . . . . E-41
E.6 A SINDA/FLUINT Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-41
E.7 The Input File: Least Squares Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-43
E.8 The Input File: MINIMAX Method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-45
E.9 Output Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-46
E.10 Thermal Desktop: Measures and Data Logger. . . . . . . . . . . . . . . . . . . . . . E-48
Input File for Sum of the Square Method. . . . . . . . . . . . . . . . . . . . . . . E-49
Input File for the MINIMAX Method. . . . . . . . . . . . . . . . . . . . . . . . . . . E-55
Processor Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-61
PROBLEM F: LH2 STORAGE TANK. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-1
F.1 Problem Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-1
F.2 A SINDA/FLUINT Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-5
F.3 The Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-9
F.4 Output Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-12
Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-14
Processor Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . F-25
iii
PROBLEM G: VAPOR COMPRESSION CYCLE. . . . . . . . . . . . . . . . . . . . . . G-1
G.1 Part 1 Problem Description: System Model . . . . . . . . . . . . . . . . . . . . . . . . .G-4
G.2 Part 1 SINDA/FLUINT Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-6
G.3 Part 1 Inputs: System Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-9
G.4 Part 1 Output Description: System Model . . . . . . . . . . . . . . . . . . . . . . . . .G-15
G.5 Part 2 Background: TXVs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-17
G.6 Part 2 Problem Description: TXV Response . . . . . . . . . . . . . . . . . . . . . . .G-18
G.7 Part 2 SINDA/FLUINT Model: TXV Response. . . . . . . . . . . . . . . . . . . . . .G-19
G.8 Part 2 Inputs: TXV Response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-22
G.9 Part 2 Outputs: TXV Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-23
Input File - System Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-28
Input File - TXV Hunting Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-39
Processor Outputs - Both System-level and TXV Transient Models. .G-46
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-47
PROBLEM H: COMPARISONS WITH CLOSED FORM SOLUTION . . . . . . . H-1
H.1 Problem Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H-1
H.2 A FLUINT Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H-2
H.3 The Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H-4
H.4 Output Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H-5
Input File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H-8
Processor Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H-13
iv
List of Figures
Figure S-1 Satellite Deployment Scenario. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-2
Figure S-2 RadCAD Depiction of Model in Orbit at Initial Position . . . . . . . . . . . . . S-3
Figure S-3 Nodal Designations Shown in Initial Position. . . . . . . . . . . . . . . . . . . . . S-7
Figure S-4 Initial, Transient, and Final Deployed Temperatures . . . . . . . . . . . . . . . S-9
Figure S-5 Parametric Temperature Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-10
Figure A-1 Toy Balloons Filled from a Tank. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
Figure B-1 Profile of the Aqueduct. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-2
Figure B-2 Idealized Pipe Cross-Section. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-3
Figure B-3 Naming Conventions for Each Pipe Submodel . . . . . . . . . . . . . . . . . . . B-8
Figure B-4 Outlet Temperature Histories for Snow Melt Event . . . . . . . . . . . . . . . B-10
Figure B-5 Outlet Flow Rate Histories for the Earthquake Event. . . . . . . . . . . . . . B-12
Figure C-1 Pressure History of the Cooker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .C-5
Figure C-2 Variation without Internal Predictive Lag . . . . . . . . . . . . . . . . . . . . . . . .C-7
Figure D-1 Aquarium Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-2
Figure D-2 FLUINT Model of Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .D-5
Figure D-3 Flow Rate Histories in Vertical Tube During Start-up. . . . . . . . . . . . . .D-10
Figure D-4 Slip Flow vs. Homogeneous Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-11
Figure E-1 Schematic of CPL GAS System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-2
Figure E-2 Condenser Plate Size and Node Names. . . . . . . . . . . . . . . . . . . . . . . . E-3
Figure E-3 Cross Section of Condenser Extrusion . . . . . . . . . . . . . . . . . . . . . . . . . E-5
Figure E-4 Schematic of FLUINT Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-12
Figure E-5 Condenser Pipe Wall Temperatures: First Two Minutes . . . . . . . . . . . E-16
Figure E-6 Condenser Pipe Wall Temperature Histories. . . . . . . . . . . . . . . . . . . . E-17
Figure E-7 Correlation Results for Both Methods . . . . . . . . . . . . . . . . . . . . . . . . . E-47
Figure F-1 Schematic of Storage Tank with Thermodynamic Vent System. . . . . . . F-2
Figure F-2 Parametric Results to Predict Optimum TVS Flow Rate . . . . . . . . . . . . F-4
Figure F-3 Schematic of Storage Tank Math Model . . . . . . . . . . . . . . . . . . . . . . . . F-5
Figure F-4 Temperature Response During Fill. . . . . . . . . . . . . . . . . . . . . . . . . . . . F-12
Figure G-1 Simplified Vapor Compression Cycle. . . . . . . . . . . . . . . . . . . . . . . . . . .G-1
Figure G-2 Two Parametric Sweeps Illustrating the Importance
of Conserving Mass. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-3
Figure G-3 Sinaps Network Diagram for System-Level Model. . . . . . . . . . . . . . . .G-12
Figure G-4 Fine and Coarse Histograms of Compressor Inlet Superheat, 
Same Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-16
Figure G-5 Typical Thermostatic Expansion Valve (TXV) . . . . . . . . . . . . . . . . . . .G-18
Figure G-6 Postprocessed FloCAD Depiction 
of the Part 2 SINDA/FLUINT Model. . . . . . . . . . . . . . . . . . . . . . . . . . .G-20
Figure G-7 TXV Response: Valve Pin Position . . . . . . . . . . . . . . . . . . . . . . . . . . .G-24
Figure G-8 TXV Response: Evaporator Flow Rates . . . . . . . . . . . . . . . . . . . . . . .G-25
Figure G-9 TXV Response: Key Qualities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .G-25
Figure G-10 TXV Response: Key Temperatures . . . . . . . . . . . . . . . . . . . . . . . . . . .G-26
Figure H-1 Water Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .H-1
Figure H-2 Temperature Profiles for All Models. . . . . . . . . . . . . . . . . . . . . . . . . . . .H-6
Figure H-3 Temperature Errors for All Models. . . . . . . . . . . . . . . . . . . . . . . . . . . . .H-7
v
vi
SINDA SAMPLE PROBLEM: SATELLITE DEPLOYMENT
This problem predicts the thermal transients during deployment of a cubic “satellite” from within
a cubic “cargo bay.” This problem was chosen to demonstrate the following SINDA features:
1. the use of submodels and BUILD commands
2. the use of steady-state, transient, and parametric runs
3. the use of array data and time-varying sources
4. the use of external radiation analysis programs such as Thermal Desktop/RadCAD®
5. the use of user character array (CARRAY) data
6. the use of user-defined files (USER1 and USER2)
7. the use of sink temperatures for model reduction
S.1 Problem Description
A hollow cubic satellite is hovering centered (i.e., negligible conductive contact) within a hollow
cubic cargo bay in low earth orbit. Within the satellite a small solid cube hovers. The cargo bay is
initially in a planet-oriented equatorial (=0°) low-earth orbit, and is open on the side facing away
from earth. When the spacecraft passes behind the earth, the satellite is deployed in the same orbit,
and is reoriented to be sun-facing (see Figure S-1 and Figure S-2). The initial and final orbital-
average conditions of the satellite are desired, as well as a simulation of the deployment event. Also,
the sensitivity to internal emissivity in the stowed condition is desired.
The relevant characteristics are:
Cargo bay (insulated on outside):
Number of panels . . . . . . . . . . . . . . . . . . . . . . . .5
Overall size . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 ft x 2 ft x 2 ft
Panel thickness . . . . . . . . . . . . . . . . . . . . . . . . .negligibly thin
Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Aluminum
Satellite:
Number of panels . . . . . . . . . . . . . . . . . . . . . . . .6
Overall size . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 ft x 1 ft x 1 ft
Panel thickness . . . . . . . . . . . . . . . . . . . . . . . . .1/8 inch
Enclosed solid cube size. . . . . . . . . . . . . . . . . . .1 in. x 1 in x 1 in.
Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Aluminum
All active surfaces:
IR emissivity . . . . . . . . . . . . . . . . . . . . . . . . . . .0.8
Solar absorptivity. . . . . . . . . . . . . . . . . . . . . . . . .0.2
Insulated at edges.
S-1
SOLAR
FLUX EARTH
SATT: 1’ cube
CBAY: 2’ cube (open 1 side)
Surfaces:  = 0.2
 = 0.8
Figure S-1 Satellite Deployment Scenario
S.2 A SINDA Model
The modeling choices reflect the importance of radiation exchange in the simulation and the
lack of conduction between surfaces. The lack of conduction means that each surface can be char-
acterized by a single temperature, and therefore can be adequately modeled by a single node. This
assumes that the temperature drop through the thickness of the thin satellite panels is negligible; a
single node is used to characterize both internal and external radiative exchange. Similarly, only one
node is chosen to represent the response of the 1 inch solid cube. The thermal capacitance of the
cargo bay is ignored; arithmetic nodes are used to represent panels of negligible mass. This would
be a good approximation if the cargo bay were insulated internally.
A separate analysis is required to characterize the radiation exchange between the sun, the earth,
the satellite, and the cargo bay, and to determine the heat flux deposition history on the spacecraft
surfaces. In this sample, such factors were supplied by the RadCAD® module of C&R Thermal
Desktop®, which can output SINDA/FLUINT style inputs including submodel distinctions.* Most
of the input file was therefore computer generated. However, because a discussion of such procedures
is beyond the scope of this manual, the reader may disregard the method by which these inputs were
derived.
* Use of Thermal Desktop as a means of supplying data for SINDA/FLUINT Insert Files is an anachronism. Such
an outdated mode is preserved here because the emphasis is on demonstrating SINDA/FLUINT usage as a
stand-alone program. Normally, this model would be built entirely within Thermal Desktop and launched
using the Case Set Manager.
S-2