A New Look At Supersonic Airliners: COK = Supersonic Junction

Narayanan Komerath Professor Daniel Guggenheim School of Aerospace Engineering Georgia Institute of Technology Atlanta, GA 30332, USA [email protected]

Thrust of the Paper • Eastern hemisphere demographics, economics, energy and carbon issues have transformed the case for supersonic airliners.

• Next supersonic airliner will use alternative fuel with high energy per unit mass.

• Technical goals are achievable.

• COK is central to the case for SST. Business case can be built around COK.

•Requests / suggestions for joint projects with Indian Business and Policy students.

INTRODUCTION

• Problem Addressed: Aerospace systems are extremely complex. As systems become more complex and ever more tightly integrated, the engineer who must innovate solutions faces an ever-increasing plethora of disciplines to understand. • The central problem considered in this paper is how to prepare learners to innovate in such an environment. • Context: School of Aerospace Engineering with ~ 700 students; BSAE class ~ 150.. • The Comprehension Challenge: What percentage of the curriculum is actually absorbed/understood?

How much can we improve this?

Why?

•

Rapid change

demands swift and confident movement across disciplines •

Cross-functional teams

require everyone to learn quickly •

Extreme complexity

and technological diversity of aerospace systems •

Breakthrough innovations

come from experience in turning dreams to reality •

Perspective

needed for innovations comes from far-away disciplines (breadth) but is applied to solve intricate problems in a core discipline (depth)

How

EXTROVERT builds on 12 year experience of the Aerospace Digital Library collection of resources, expanding and refining the resources.

• Intuitive gateway to AE based on conceptual design of flight vehicle systems, • suited to learners at all levels. • Allow any user to go up to the perspective of the general public, and down to • level of detail needed for R&D. • Detailed sequential course notes, linked across disciplines. • Worked Examples, Concept Development examples, Case Studies • Continuous, modular learning assessment, focused on learning.

Evolution Of The EXTROVERT Idea

•Iterative learning experiments 1994 • Design-centered introduction to aerospace engineering, 1997 • “Aerospace Digital Library” website in sustained operation since 1998 •Depth vs. breadth: Vertical Streams of Technical Content • Cross-linking vs. Search Engines •Catering to multiple learning styles, 2002 •Concept development exercises, 2002 •Case studies, 2009 •Learning Fundamentals through Conceptual Design

PRIOR WORK

1992 – 94: Learning by Iteration. NSF Leadership in Laboratory Development award bring the essence of practical experience into coursework. Lessons applied to core aerodynamics courses.

1997-2000: Learning Fundamentals through Conceptual Design. Freshmen perform very well in conceptual design applied to aircraft.

1998: Design-Centered Portal to Aerospace Digital Library. Goal: make information from every discipline available from the level of a high-school through college.

1998 – 2008: Vertical Streams of Technical Content; Cross-linking; Learning Styles. 2002-2005: Experiences with the NASA Institute of Advanced Concepts 2004: Boeing Welliver Experience. Imperative for depth of comprehension.

Concept essays and concept modules provide succinct introductions to vertical knowledge streams.

CE Examples

•Antenna Design •Fluid dynamic Drag •Aerodynamic Lift •Brayton Cycle Engine • Vortex Flows

New Realities

Core knowledge content is distilled into vertical streams in specific disciplines from freshman to doctorate levels. Low and high speed steady aerodynamics, flow diagnostics and control techniques, unsteady aerodynamics, jet propulsion, rocket and space propulsion, and composite materials, dynamics, vehicle performance, flight mechanics and controls, high temperature gas dynamics, and aeroelasticity. 24/7 – 365 access from anywhere. Includes •Worked examples on-line. • Module-based assessment through thought surveys.

•Concept Development assignments in courses and research projects.

•Case Studies from history and current projects •Skills Library • Realistic, large, open-ended assignments in classes, well beyond single course. •Intense undergrad participation in research; peer-reviewed publication.

Combining geometric engine from CAD software with supersonic wave drag calculation using MatLab

Concept Development Example: Tethered Aerostats to transmit 200 GHz electric power through lower atmosphere.

Komerath, Pant and Kar, Journal of Low Power Electronics, July 2012

DISCUSSION POINTS 1.

2.

Resistance to “derivations”; tendency to depend on memorized formulae Difficulty with order of magnitude estimation (“sense of the numbers”) 3. Resistance to going outside minimal syllabus. 4. Thought survey questions on tests 5. No place to hide. 6. Resource glut? Providing access to prior materials brings resentment!

On the other hand: The top half of the class performs far beyond what their predecessors could do. Amazement at how much they learned. The top 30% “get” what we are trying to do for them – the core of the future aerospace industry.

CONCLUSIONS Rationale, development and usage experience of new resources to enable innovation in complex problems crossing several disciplines.

1. A portal set in conceptual design conveys a quick and useful perspective, and entry to depth.

2. Vertical streams of content provide continuity and integration 3. Concept essays and concept modules provide succinct introductions.

4. Advanced concept explorations help learners build estimation skills.

5. Usage of resources allows the best to run far out ahead, while improving all.

6. Highlights major issues in traditional class practices.

7. Concept development teaches innovation in the face of large uncertainty. Advanced concept development experience and iterative experience in course formative evaluations, teach students to conduct order-of-magnitude estimates to bolster their problem-solving approaches. 9. A return to rigorous fundamentals is consistent with experiential learning.

10. The new capabilities call for a re-examination of the traditional assumptions about course structure and performance assessment.

SUMMARY OF OBSERVATIONS

Use of “skill” tools Intrinsic ability (when pushed) Applying “theory” learned in classes Capturing essence of logic methods Using analysis to develop bounds

ACKNOWLEDGMENTS This work is funded by NASA under the Cross-Disciplinary Innovation initiative. Mr. Tony Springer is the Technical Monitor.

CROSS-DISCIPLINARY LEARNING

• Adapting to evolving technology, knowledge resources & project needs • Breadth vs. depth • Different learning styles critical to motivation, • Innovations from all quarters, require depth and breadth to understand and refine.

SUCCESSES – AND ISSUES ENCOUNTERED

Target is depth of understanding and breadth of capabilities: encounters stiff resistance from “experienced” students who “know” what should be taught.

- freshmen complained about intense calculations and learning in 1 st 6 weeks of conceptual design assignment (short-range airliner), but then repeated those calculations in 1 week (LH2 fuelled short-range airliner) and then did the essential parts of the design as one of six questions on a 3-hour final.

Seniors in AE3021 had a good deal of trouble with the small conceptual design part preceding supersonic airplane drag calculation. Concept of developing a “figure of merit” for a given design from the ideal, was missed by most. Graduate students in AE6020 (transonic and hypersonic aerodynamics) were in deep trouble as the availability of “assumed” undergraduate knowledge and examples made “thought” questions fair game on closed book tests; several then did extremely well on take-home open ended, integrative “final exam”. Some still did not “get” the idea that one was expected to deliver well-thought-out quantitative answers, not just “suggestions”.

Cross-disciplinary Project Examples

• Liquid hydrogen supersonic transport concept development, including demographics, economics, carbon market issues. • Space Power Grid approach to Space Solar Power. • Micro Renewable Energy Systems courses and testbeds.

• Retail Power Beaming • Microgravity flight tests.

• Force-field Tailoring of objects in reduced gravity.

Course experience

•Introduction to aerospace engineering •Low speed aerodynamics •Vehicle Performance •High speed aerodynamics •Aeroelasticity •Graduate high speed aerodynamics •Graduate Propulsion Design

Assessment Results

1. Formative assessment and evaluation results from courses.

2. Survey site ( http://www.surveymonkey.com

) linked into courses. 3. Experience of student learning styles and preferences through discussion fora set up in course management websites. 4. Initial learning styles survey of students in different courses. 5. Formative survey modules in 3 courses. Being technical in nature, students (should) have somewhat strong motivation to answer these. 6. Focus Groups in 4 classes

Focus Group Results

•Course notes from the instructor were the most heavily used •Textbook, •Student notes from class, •Exams from previous semesters •Working with friends, and •Examples obtained from the Internet. •“Back of the envelope estimates" and "solved problems from the ADL/EXTROVERT library“ rank at the bottom.

•Module-based surveys have become excellent resources as knowledge integrators

ACKNOWLEDGMENTS

This work is funded under the NASA Innovation in Aerospace Instruction” Initiative. Mr. Tony Springer is the Technical Monitor.

Discussion

Resource Usage: Aerospace Digital Library resources first iteration used in the classroom in Fall 2010 alumni and others who need quick, accurate guidance Design Build Fly team usage

Undergraduate Research Tools eBooks

Concept Exploration LH2 SST Supersonic drag estimation Missile Defence System Aerostat Design

eBooks

Space Power Grid Retail Power Beaming

Learning styles

What types of resources are you most likely to FIRST TRY, when you are trying to learn a subject (for instance, as you prepare to do an assignment for an engineering class?)

Is technological change really more rapid today than, say, in 1940 or 1960?

Are today’s engineers able to deal with concept innovation better?

Aerospace engineering requires depth of understanding. Engineering curricula are designed on the reasoning that a firm foundation in basic disciplines gives the graduate a lifetime to gain breadth. The intense, demanding and rigorous college experience also instills confidence and persistence to approach tough problems.

Traditional curriculum with linear course sequences coming together in senior year “capstone” design experiences, was appropriate for Cold War era, large company recruiting that emphasized corporate training after school. Small-team requires better comprehension levels, experience and perspective through research participation and other learning by iteration.

Depth and breadth compete for shrinking learning time.

Project Objectives:

• Build resources for problem-solving across disciplines

to develop new concepts.

• Acquire experience on how engineers perform in such learning.

Approach:

Enable learners to gain confidence with the process of solving problems, -starting with their own preferred learning styles.

Ideas being implemented

•Case Studies •Library of solved problems include: •Design-centered portal to aerospace engineering •Vertical streams of technical content •Integrative concept modules • Module-based assessment to measure learning in time to improve it.