University Turbine Systems Research Fellowship 2011Caterpillar Confidential: Green Coriolis Rig Background • Background - Coriolis Rig examines the effects of rotation on internal

Rob Murphy Academic Advisor: Dr. Andrew C. Nix

Heat Transfer Group

Supervisor: John Mason Group Manager: Hee-Koo Moon

Mentor: Yong Kim

University Turbine Systems Research

Fellowship 2011

Coriolis Rig Heat Loss Validation and New Test Section Design

Caterpillar Confidential: Green

Learning Experience Acknowledgements

About Me Projects

Agenda

- Coriolis Rig Heat Loss Validation - Coriolis Rig Endwall Investigation - New Test Section Design


About Me

Education: • West Virginia University – Morgantown, WV

• Bachelor of Aerospace Engineering • Bachelor of Mechanical Engineering

• Master of Mechanical Engineering (May 2012) • Advisor: Dr. Andrew C. Nix

• Focus: Gas Turbine Heat Transfer • Thesis Topic: Study of the Effects of Particulate Deposition on Heat Transfer

• National Energy Technology Laboratory (NETL) – Morgantown, WV • Oak Ridge Institute of Science and Education (ORISE) Fellow 2011

• Mentor: Doug Straub • Duties: Assist in setup of LDV system, particle seeder installation, assist in other Turbine Project areas

Activities: • Engineers Without Borders

• Nicaragua Water Filtration Project Lead • President

• College Recruiter


Coriolis Rig Background

•  Background -  Coriolis Rig examines the effects of rotation on

internal cooling schemes

-  Two wing-shaped arms

•  Up to 750RPM •  Temperatures at 120F, 140F and 180F

-  3-Pass Serpentine Channel •  Heaters on Pressure Side, Suction Side

and endwall region of test section

•  Two cases: Smooth Channel and Trip Strip

•  Objectives -  Validate Current Heat Loss Model in ANSYS

Thermal Workbench

-  Examine Endwall Region in ANSYS to examine low heater outputs during trip strip runs

-  Design new test section for future cooling schemes


Corilois Rig Model Setup

• Step 1: Start with current model provided by Solar

• Step 2: Cut away sections to get the area that will be analyzed


Coriolis Rig Model Setup

• Step 3: Insert Required Components such as: copper plates, silicon inserts, insulation and aluminum wing

Aluminum Shell

Silicon Spacer

Polystyrene Insulation

Copper Plates


Corilois Rig ANSYS Thermal Analysis

• Imported model into ANSYS

• Applied Thermal Properties to Components

• Meshed Model

• Begin Applying Boundary Conditions


Coriolis Rig ANSYS Boundary Conditions

•  Law of Symmetry -  Highlighted in Blue

-  Modeled by applying perfect insulation to the front, top and right side of the model

•  Natural Convection

-  Highlighted in Yellow

-  Simulating the low heat transfer occurring in the channels that house the wires

•  Perfectly Insulated channel to simulate the insulation present in the actual heat loss test


Coriolis Rig Outer Heat Loss Boundary Condition

• Outer Convective Heat Transfer Coefficients were calculated using Newton’s law of cooling

•  h values were calculated for each rotational case

( )avgcageavgwingsurface TTAQh

,, −=

RPM h (BTU/hr-ft^2-F)

0 6.78350 7.64600 9.29750 10.27

Table 1: h Values at Four RPM Cases


Coriolis Rig Heat Loss BC Application

•  For 0 RPM Case the h value was applied to the entire outer surface

•  For the rotating cases the h value was applied on the two faces highlighted to the right. The other part of the face was given a low h value to simulate its attachment to the wing


Coriolis Rig Heat Loss Results

•  0 RPM Heat Loss Case ANSYS vs. Experimental



Coriolis Rig Heat Loss Results




Coriolis Rig Heat Loss Validation Conclusions

• Most Plate Temperatures were within 5% of experimental data

•  Plate 15 was off my more than 10% in most cases due to an instrumentation error

•  These results prove that the heat loss assumption is valid.

- The heat can only escape out of the outer faces with the current setup so the correlation between the ANSYS and Experimental plate temperatures validate the assumption


Coriolis Rig Endwall Analysis

• Ran Model with Flow Cases

• Model Setup the same except in the channel

• Convective Heat Transfer Coefficients that were calculated by Solar engineers in a previous data reduction project were applied to the plates, spacers and walls of the channel

• With the heat loss validated results should be accurate within the margin of error if the heat transfer coefficients were calculated correctly


Coriolis Rig Endwall Results

•  Low Flow 0 RPM Smooth Channel Case ANSYS vs. Experimental

•  Low Flow 0 RPM Trip Strip Case ANSYS vs. Experimental


Coriolis Rig Endwall Conclusions

• Good Correlation (<10%) for most of the first pass plates

•  The second pass plates had a discrepency that increased along the flow path. This was believed to be caused by a heat flux that would be coming through the wall separating the 2nd and 3rd pass. This heat flux was not modeled in the current setup.

•  There is a distinct difference at the endwall regions. The smooth case has a similar trend to the experimental data and matches up well. The trip strip data does not match up well and has the opposite trend of the experimental data.


Coriolis Rig Endwall Conclusions

•  The endwall was examined to look for instrumentation or thermocouple errors but none were found.

•  Since the heat loss scheme was validated and there were no instrumentation errors found, the author believes that there must be some unknown flow patterns not being considered in the current data reduction scheme. With the HTC values calculated in the data reduction the plate temperatures should be lower than what was recorded in the experimental data.

•  Future tests are being planned to examine what effects changing the flow pattern will have on the endwall region.


Coriolis Rig New Test Section Design

• New test section design will have two channels

- One channel will have pin-fins and the other will have trip strips

•  Two channels are part of new cooling scheme for turbine blades

•  Analytical studies showed a heat transfer degradation on the suction side so a new test section will examine that

• No geometric values will be provided for the model because they are proprietary property of Solar Turbines, Inc.


Coriolis Rig New Test Section Core

• Constructed core from geometry taken at a cross section of the actual design

•  Formed two straight channels that are 5X scale of actual blade


Coriolis Rig Copper Plate Design

•  The core was used to create the negative space in the channels

• Once the channels were created copper plates of both channels were made


Coriolis Rig New Test Section Sides

• Once the plates were completed they were assembled together to form the pressure (top) and suction (bottom) side of the new test section.


Coriolis Rig Future Work

•  These items were not completed at the time this presentation was due

• Create entrance length for test section to mimic entrance length of actual cooling passage

•  Size heaters based on ratios using actual engine conditions

•  Place channels for thermocouple wiring on model

• Contact vendors to order new material for test section and heater manufacturing


Learning Experiences

•  Programs

-  ProE

-  ANSYS Workbench

• Skills

• Modeling 3D Heat Transfer Problems

• Performing Diagnostics on Model

• Test Section Design

• Coriolis Effects on Heat Transfer

• Troubleshooting Experimental Data Reduction


Acknowledgements

•  WVU -  Dr. Andrew C. Nix

-  CAFEE

•  SwRI

-  Dr. Klaus Brun

-  Andrea Barnett

•  NETL

-  Doug Straub

Yong Kim

Ross Myers

Gail Doore

Archie French

Steve Pointon

Charmaine Gary

Matt Mayer

Hee-Koo Moon

John Mason

Tim Bridgman

Heat Transfer Group

The Rotations

The Interns

Everyone else who helped…

Documents

University Turbine Systems Research Fellowship 2011Caterpillar Confidential: Green Coriolis Rig Background • Background - Coriolis Rig examines the effects of rotation on internal