{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

q7p_sol - Unified Engineering Propulsion Quiz Spring 2004...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Unified Engineering Propulsion Quiz NAME: SOLUTIONS ___ Spring 2004 Unified Propulsion Quiz May 7, 2004 Closed Book – no notes other than the equation sheet provided with the exam Calculators allowed. Put your name on each page of the exam. Read all questions carefully. Do all work for each problem on the pages provided. Show intermediate results. Explain your work --- don’t just write equations. Partial credit will be given (unless otherwise noted), but only when the intermediate results and explanations are clear. Please be neat. It will be easier to identify correct or partially correct responses when the response is neat. Show appropriate units with your final answers. Box your final answers. Exam Scoring #1 (15%) #2 (25%) #3 (15%) #4 (20%) #5 (25%) Total 1
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Unified Engineering Propulsion Quiz NAME: SOLUTIONS ___ Spring 2004 Below is a photograph of the Joint Strike Fighter (JSF). A lift fan (directly behind the cockpit) is driven by a shaft from the main engine to provide vertical take-off and landing capability. The exhaust nozzle on the main engine can also swivel 90 degrees to point directly down. The inlet for the main engine is split, with half the flow coming in either side of the cockpit, flowing through a y-shaped duct (with the shaft running through it) that wraps around the lift fan and meets in the center of the aircraft. There are also two small roll-control jets that exit the main engine aft of the compressor. U.S. Air Force photo 1. (15 points, partial credit given, L.O. C & D) What are the principal figures of merit for an engine of this type and why? When answering this question be sure to describe how these figures of merit are related to overall vehicle performance. The principal figures of merit for gas turbine engine performance are max-thrust, overall propulsive efficiency, impact on vehicle weight and impact on vehicle drag. These parameters directly impact mission performance for example: h L d Ê 1 W ˆ Range = h overall D l n W initial and for maneuvering: T V - D V = W dh g W final dt + dt Ë Á 2 g V 2 ¯ ˜ For this vehicle, the engine configuration alone suggests that maneuvering, especially vertical take-off and landing, is of great importance to the mission. Therefore an additional figure of merit would be the capability to reconfigure or vector the thrust. In addition to the performance figures of merit, it is important to add cost (acquisition cost and non-fuel operating costs).
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern