This document summarizes the final technical report for a project to design and build a microchannel heat exchanger flow loop. Key accomplishments include constructing and validating the flow loop, developing experiment manuals for measuring friction factor and Nusselt's number, and delivering all work to the client on time and to specifications. Recommendations include expanding experiments to study two-phase flow and slug flow, and potential flow loop improvements like better sensors and housing design.

1. Microchannel Heat
Exchanger Flow Loop
Team 16 Final Technical Report
April 29, 2015
MECE: Capstone 2014-2015
Jeremy Evans, Olivia Pacheco,
John-Roland Espinosa, Michael Russo

2. Outline
 Project Background
 Statement of Work
 Deliverables and Validation
 Methodology
 Results and Accomplishments
 Conclusion
 Recommendations

3. Introduction to Problem
http://upload.wikimedia.org/wikipedia/commons/2/25/AMD_heatsink_and_fan.jpg http://h10025.www1.hp.com/ewfrf-
JAVA/Doc/images/1003/c03904186.jpg

4. Background
Heat flux can reach

5. Background (make eq. more readable)
𝒇 =
∆𝑷𝑫 𝒉
𝑳
𝟎. 𝟓𝝆𝑼 𝟐

6. Statement of Work
1. Create a coolant flow loop incorporating a
microchannel heat exchanger to be used in MECE
4371
2. Compose a flow loop manual
3. Write two lab experiments for students to
conduct in MECE 4371 dealing with fluid and
thermal theories

7. Deliverables and Validation
 A completed flow loop containing a microchannel heat
exchanger
 Two lab manuals incorporating the completed flow loop to
be used for experiments in MECE 4371
 Experimental temperature and pressure data with
theoretical correlations
 Coolant loop performs as specified by Dr. Liu

8. Methodology & Process
• Research
• Internet
• MECE coursework
• Dr. Liu’s thesis
• Analysis to determine required
components and specifications
• Determine theoretical predictions,
required formulas and relations
• Receive and test all ordered components
• Prime the pump
• Assure that voltage conversions are
safe and accurate

9. Methodology & Process
Flow rate to remove optimal heat
flux:
𝑞 𝑠
"
=
𝑚𝑐 𝑝
𝑃𝐿
(𝑇 𝑚𝑜 − 𝑇 𝑚𝑖)
𝑇 𝑚 𝐿 = 𝑇 𝑚𝑖 +
𝑞 𝑠
"
𝑃𝐿
𝑚𝑐 𝑝
𝑇ℎ𝑒𝑟𝑒𝑓𝑜𝑟𝑒 𝑚 = 169.51
𝑚𝐿
𝑚𝑖𝑛
𝑖𝑠 𝑡ℎ𝑒 𝑔𝑜𝑎𝑙 𝑓𝑙𝑜𝑤 𝑟𝑎𝑡𝑒
Pressure drop calculation from
friction factor definition:
𝑓 = 0.08 = 𝑐𝑜𝑟𝑟𝑒𝑐𝑡𝑒𝑑 𝑓𝑟𝑖𝑐𝑡𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟
𝛥𝑃 = 𝑓
𝜌𝑢 𝑚
2𝐷ℎ
= 0.8 𝑝𝑠𝑖
Required capability of heat cartridges in order to attain desired
100
𝑾
𝒎 𝟐 heat flux:
𝐶𝑟𝑜𝑠𝑠 − 𝑠𝑒𝑐𝑡𝑖𝑜𝑛𝑎𝑙 𝑎𝑟𝑒𝑎 𝑜𝑓 𝑐𝑜𝑝𝑝𝑒𝑟 ℎ𝑒𝑎𝑡 𝑒𝑥𝑐ℎ𝑎𝑛𝑔𝑒𝑟 𝑏𝑒𝑙𝑜𝑤 𝑐ℎ𝑎𝑛𝑛𝑒𝑙𝑠 = 3.884 𝑐𝑚2
𝑇𝑜𝑡𝑎𝑙 𝑝𝑜𝑤𝑒𝑟 = 𝐻𝑒𝑎𝑡 𝑓𝑙𝑢𝑥 ∗ 𝑎𝑟𝑒𝑎 = 388.4 𝑊
𝑃𝑜𝑤𝑒𝑟 𝑟𝑒𝑞𝑢𝑖𝑟𝑒𝑑 𝑝𝑒𝑟 ℎ𝑒𝑎𝑡 𝑐𝑎𝑟𝑡𝑟𝑖𝑑𝑔𝑒 =
𝑇𝑜𝑡𝑎𝑙 𝑝𝑜𝑤𝑒𝑟
# ℎ𝑒𝑎𝑡 𝑐𝑎𝑟𝑡𝑟𝑖𝑑𝑔𝑒𝑠 = 8
≈ 50 𝑊 𝑝𝑒𝑟 𝑐𝑎𝑟𝑡𝑟𝑖𝑑𝑔𝑒

10. Methodology & Process
• Construct flow loop (precision required!!)
• Determine component layout
• Cut and bend steel piping
• Machine G10
• Build and implement fixtures for pump,
rotameter, MCHX assembly and
condenser
• Configure software
• Set up data acquisition multiplexer with
TC and PT connections

11. Methodology & Process
• Run Nusselt’s Number and Friction Factor experiments and document
processes
• Compare measured data for experiments with theoretical predictions and
provide to client
• Document flow loop operation instructions

12. Results/Accomplishments
1. Milestone 1 – Component
Fabrication and Procurement
Completed
2. Milestone 2 – Flow Loop Assembled
3. Milestone 3 – Flow Loop and
Experiment Documentation
4. Milestone 4 – Final Design Validated
for Client
COMPLETED
COMPLETED
COMPLETED
COMPLETED

13. Results/Accomplishments
1. Flow Loop Constructed and Validated
 Show temperature and pressure data vs. flow rate, explain the
trends that were sought, etc.
 Show pictures of completed flow loop
2. Friction Factor Experiment and Validation
 Show f*Re plot with theoretical curve
 Show theoretical relation
3. Nusselt’s Number Experiment and Validation
 Show f*Re(???) plot with theoretical curve
 Show theoretical relation

14. Results/Accomplishments
 Flow loop constructed

15. Results/Accomplishments

16. Item Cost Vendor
Gear Pump with AC Motor and Controller $1,434.00
Cole Parmer
Groundwater Filter 5.0UM $47.25
Turbine Flowmeter $75.00
Copper Liquid-Liquid Heat Exchanger $319.00
Lytron
Stainless Steel Reservoir $350.90
McMaster-Carr
T-Type Thermocouple $18.50
Stainless Steel 0.25” Piping 6 feet $19.42
Swagelok fittings, control valves and bypass $1,500.00
Swagelok
Reverse Osmosis Water $40.00
Data Acquisition (DAQ) and module with
software and connections
$499.00
Ebay
G-10 Material $51.01
Cartridge Heaters $372.00
Omega
Pressure Transducers $450.00
Soft insulating material (Mylar Blanket) $4.00
High temperature sealant and Locktight $9.00
Polycarbonate $12.33 US Plastic Corp
Stainless Steel Cart $149.33 Amazon
NPT Reducers for PT Connection $16.89
Summit Racing
TOTAL $5367.63
Results/Accomplishments (update numbers)

17. Conclusion
 Thermal management is gaining priority as the
number of transistors per IC increases in modern
computers.
 The flow loop, its manual, and both experiment
manuals have been completed and delivered to the
client on time and were approved

18. Recommendations
 Extensions to experiments:
 2 – phase flow experiments
 Slug flow experiments
 Improvements to flow loop:
 Pressure transducers with increased voltage range
 More accurate rotameter
 Different housing design – improved fit between copper block
and housing, easier manipulation of o-rings