Heat Exchanger By: Kayla Badamo, Josh Lutton, and Daniel Jackson - PowerPoint PPT Presentation

Heat Exchanger By: Kayla Badamo, Josh Lutton, and Daniel Jackson Edesign 100 Section 026

Outline • Mission Statement and Target Improvements • Background Research • Criteria • Initial Concepts and Solution • Testing • AM limitations and comparison with SM • Cost and Build Time • Conclusion

The Customer and Our Mission Statement • Our customer is Lockheed Martin. • The goal is to optimize the design of one of their heat exchangers for additive manufacturing.

Target Improvements • Create a more effective heat exchanger by increasing surface area without detracting from other design specifications such as airflow.

Background Research • Two concepts affect the heat transfer (1) • Area of the material • Thermal Conductivity of the material • To improve this heat exchanger, we need to increase the surface area and use a material with a high thermal conductivity.

Criteria and importance • Increase Surface Area • Maintain air flow level in order to remove heat. • Approximately the same weight since it is on a aircraft. • Maintain same external dimensions since it still needs to fit in a small space • Reduce cost and build time to expedite manufacturing

Initial Concept Ideas • Large two-way hexagons • small two-way hexagons • small one-way hexagons

Large two-way hexagons

Small two-way hexagons

Small one-way hexagons

Design Selection Matrix

Chosen Concept • Small two-way hexagon lattice structure • Greatest surface area

3D Printed Prototypes

Conducted Tests • Flow test • Air flow test • Calculated Weight • Calculated Surface Area

Flow Tests • For the flow test, we poured water through the prototype to see how well it flowed through. • For the air flow test, we shot compressed air through the prototype against a piece of paper to make sure it had a good airflow.

Calculated weight • We used Solidworks mass properties to calculate the weight of our prototypes. We also changed the material to aluminum to get a realistic number. • Original- 2.87 pounds • Large two-way- 2.06 pounds • Small one-way- 2.48 pounds • Small two-way- 5.39 pounds

Calculated Surface Area • We used the surface area calculator in Solidworks and compared it to the original surface area • Original- 1039 square inches • Large two-way- 640 square inches • Small one-way-1658 square inches • Small two-way-2959 square inches

Limitations of AM • Minimum feature size • Orientation had to be right so we didn’t need supports

Benefits AM vs Subtractive Manufacturing • Allows geometries that are difficult to achieve with subtractive • Lower cost than subtractive • Allows for on-site manufacturing and shorter supply chains • Allows low volumes of custom parts • Less waste material left over [4]

Recommended Manufacturing Method and Material used • Powder Bed Fusion (direct metal laser sintering) • Directed energy deposition (fast rough surface) not optimal for this project • Use Aluminum as the material • High heat conductivity and heat transfer

Cost and Build Time • DMLS Aluminum powder is $.45 per square centimeter (2) • $.45 x 19000 square centimeter= $8,550 • Direct metal laser sintering machine build speed is .001 cubic inches per second (3) • Volume of chosen concept – 54.8 cubic inches per second • 54.8/ .001= 54800 seconds= 152 hours= 6.3 days

Fulfillment of Design Goals • Two prototypes increased surface area, one by ~60% and one by ~300% • Two prototypes decreased weight, the one that increased weight dramatically increased surface area. • Minimal impact on airflow maintains functionality

Conclusion • Lockheed Martin wanted us to improve their heat exchanger using additive manufacturing • We increased surface area and used a good heat conductor for our heat exchanger because that makes it more efficient • Our design tripled the surface area and kept a good air flow • We recommend using Powder bed fusion (direct metal laser sintering) as the AM method and using aluminum as the material because it is a good conductor of heat. • We learned about methods of AM and why they are better than subtractive methods. We also learned how to work well as a team.

References 1. Concord.org. "Heat Transfer." AccessScience (n.d.): n. pag. Concord . The Concord Consortium. Web. 2. Shapeways.com. "Aluminum 3D Printing Material Information - Shapeways." Shapeways.com . Shapeways Inc., n.d. Web. 26 Apr. 2016. 3. Dmlstechnology.com. "DMLS Machines." DMLS Machines . DMLS Technology, n.d. Web. 26 Apr. 2016. 4. http://www.raeng.org.uk/publications/reports/additive-manufacturing "Additive Manufacturing: Opportunities and Constraints" . Rep. Royal Academy of Engineering, 23 May 2013. Web. 25 Apr. 2016.