Download Hydraulic System Design Requirements Agreement 2 September

IV
EELV
A Thermal Hydraulic Model
for Expendable Launch
Vehicles
Michael Berglund
Delta IV Launch Vehicle Development
May 16-17, 2000
Created by
Michael Berglund
1
IV
EELV
Outline
Point 1 - Correlation with Test Data
Rocketdyne
Thermal analysis
DT-1 RCN
Point 2 - Design Tool, Test Transient Conditions
Point 3 - Common Modeling System
Rocketdyne
Controls group
Point 4 - Good Customer Support
New Parts Specified
Modeling Hydraulic Systems Using EASY5
Summary of EASY5 Process
Created by
Michael Berglund
2
IV Easy5 Model of RS-68 Hydraulic System
EELV
Heat Transfer Analysis: EJ Reott
 ACTUATOR
VERIFICATION
 VM fluid output temp
TF2VM
 FO fluid output temp
(corrected)
TF2
 Matches MHI Data
(error +/- 3.7%)
Created by
Michael Berglund
3
IV Easy5 Model of RS-68 Hydraulic System
EELV
Heat Transfer Analysis: EJ Reott
 LINE SEGMENT
VERIFICATION
 Heat transfer from fluid to
wall (BTUH)
QFPI
 Heat transfer from fluid to
wall (corrected)
QFPI11
 Wall temp
TWPI
 Wall temp (corrected)
TWPI11
 Matches Calculation
(error +/- 0.4%)
Created by
Michael Berglund
4
IV
EELV
Fluid Temp Rise Across Orifice
TVC1, TVC2, RCN
 EASY5 model: oil temp
rise across orifice results:
 T = 76°F
 Hand Calculations: Oil
temp rise across orifice
(same conditions) results:
 T = 75.9°F
Created by
Michael Berglund
5
IV
EELV
Created by
Michael Berglund
Fluid Temperature Rise In Flight
6
IV
EELV
Development Test Models (major assumptions)
 Development Test Models
 DT_RCN (boundary conditions, spring force)
 DT_TVC (boundary conditions, spring + constant force)
 DT_Breadboard (valves simulating flow demand for all actuators, single
valve representing all 4 engine valves)
 DT_System (TVC, RCN actuators included, single valve representing all 4
engine valves)
 Hydraulic_System (same as DT_System but with engine valves from
Rocketdyne)
Created by
Michael Berglund
7
IV
EELV
Created by
Michael Berglund
EASY5 DT-1 RCN Model
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IV
EELV
RCN Velocity and Stroke
Stroke & Velocity vs. Time
20.0
Velocity Transducer
15.0
LVDT-in.
Calculated LVDT
Stroke-in, Velocity-in/sec
10.0
5.0
0.0
-5.0
-10.0
-15.0
-20.0
0.0
0.5
1.0
1.5
2.0
2.5
Time (sec)
DT-1 RCN
Created by
Michael Berglund
EASY5
9
IV
EELV
Force Data
3000
Force
2000
Force (lb)
1000
0
-1000
-2000
-3000
0.0
0.5
1.0
1.5
2.0
2.5
Time (sec)
DT-1 RCN
Created by
Michael Berglund
EASY5
10
IV
EELV
DT-1 RCN & Model Correlation
Force Data
3000
Force
2000
Force (lb)
1000
0
-1000
-2000
-3000
0.0
0.5
1.0
1.5
2.0
2.5
Time (se c)
Spring Characteristics
of Air Spring
3000
2000
Force (lbs)
1000
0
-1000
-2000
-3000
-6.0
-5.0
-4.0
-3.0
-2.0
-1.0
0.0
1.0
2.0
3.0
4.0
5.0
Stroke (in)
Stroke vs. Time
10.00
LVDT-in.
Stroke-in, Velocity-in/sec
5.00
0.00
-5.00
-10.00
0.0
0.5
1.0
1.5
2.0
2.5
Time (se c)
DT-1 RCN
Created by
Michael Berglund
EASY5
11
IV
EELV
Common Modeling System
 Rocketdyne
 Received and integrated
Rocketdyne’s EASY5 model
into CBC EASY5 model
 Controls Group
Created by
Michael Berglund
12
IV
EELV
New Components
 Found in New EASY5 Library
 AD (accumulator with an inlet and outlet), Qin, Qout for
both fluid and gas, EFX heat flux
 PI - Pipe with heat flux
 VO - Volumes with heat flux
Created by
Michael Berglund
13
IV
EELV
Created by
Michael Berglund
New Accumulator
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IV
EELV
EASY5 New Components
 New Parameters: EFX and QIN
 EFX defines additional energy
flux into the volume wall. EFX
units are BTUH/in2.
 QIN defines additional heat
generated internally within the
fluid. QIN units are BTUH
Created by
Michael Berglund
15
IV
EELV
Conclusions
 EASY5
 Test correlation
 Design tool, test transient conditions
 Common modeling system
 New parts specified
 Recommendation: Continue to use EASY5 to model
hydraulic system
Created by
Michael Berglund
16
IV
EELV
Modeling Hydraulic Systems Using
EASY5
 EASY5 Process
 Building a Model
Created by
Michael Berglund
17
IV
EELV
EASY5 Process
 Define system and the EASY5 model objective
 Build Model by Placing and Linking the
Components in the Correct Sequence (use only
default or port connection method)
 Create an Executable File
 Find an Initial Operating Point (All Time
Derivatives = Zero)
 If the Model Equations Converge, Run a
Simulation
 Plot Any Output As a Function of Time
Created by
Michael Berglund
18
IV
EELV
Building the Model
 Start with simple foundation model, ie, valves for actuators,
volumes instead of accumulators, no tabular functions,
average values
 Run to see if results make sense, check with other team
members (in the ball park values)
 Build on model, make more complex if preliminary model
checks out
 Make thermodynamic model as simple as reasonably
possible because of potentially large simulation times
Created by
Michael Berglund
19
IV
EELV
Actuators Approximated by
Metering Valves
Similar to Breadboard Development Test
set-up
Created by
Michael Berglund
20
IV
EELV
Created by
Michael Berglund
Model of TVC Actuator
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IV
EELV
Created by
Michael Berglund
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IV
EELV
Created by
Michael Berglund
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IV
EELV
Created by
Michael Berglund
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