Aerospace Design and Practice

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Aerospace Systems Design

Acoustics and Noise Control

Aerodynamics and Heat Transfer

Aerospace Vehicle Performance

Aircraft Stability and Control

Aerospace Propulsion

Introductory Aeroelasticity

Composite Materials

#rnL CARLETON IINTVERSITY FINAL EXAMINATION December 2002 DURATION:3 HOURS No. of Students:57 Department Name & Course Number:Mechanical & Aerospace Engineering AERO 4302nvIEcH 5000 Students MUST countthe numberof pages in this examination question paperbefore beginningto write, and report any discrepancy immediately to a proctor. This question paper has 5 pages. This examination question paper MAY be taken from the examination room. In additionto this question paper,students require: an examination booklet yes _x_ no _ a Scantron sheet yes _ no _x_ N.B. 1) Use the standard symbols and sign conventionsof the lectures throughout your answers. This practise has been followed in the test questions. 2) Neatness and legibility are important 3) Attempt all5 questions l. (25marks) The function(f + xy/ is alleged to be a valid stream function for a steady two-dimensional water flow (P : 1000 kg/mi)' Check if this is true. If the velocity-component valuesare to haveunits of z/s, and x andy arein m, what must the units of the streamfunction be? Assuming that the given function is indeed a valid stream function, does it represent an irrotational flow? Support your answer. Assumingthat this is a steady flow, obtaina formula for the x-component of acceleration of fluid particles at any point (x. y) in the flow field. What is this acceleration at the point (x, y) = (2,3) ? Would it be valid to apply Bernoulli'sequation between points (2, 3) and (5,2.1) ? Support your answer with suitablecalculations. If the staticpressure at (x, y) : (2,3) is + 3.3 kN/m2 gage what is the static pressure at (x, y) = (5, 2.1) assuming that Bernoulli's equation can be usedbetween these fwo points in the flow? MEMoRANDA OPEN BOOK Calculators allowed a) b) a) d) e) f &<_. //c Find a formula for the angle of attack for zero lift (relative to the chord line) for any value of Hc and determine this angle,in degrees, if Hc = 0.03 What is the lift coefficient for an angle of attack, relativeto the chord line, of +4.0 deg. if Hc: 0.03 ? By how much would the lift coefficient of part (b) changeif the angle l. (seethe sketch) were doubled but the rest of the camberline were unchanged? Sketchthe distribution of pressure-coefficient difference along the airfoil, that is (Cp, - (p,) versusx/c, for the conditions of part (b). The sketch neednot be to scale but pay particular attention to the qualitative behaviour of (Cp1 - Cp,) near the breaks in the camberline slope . Cp, and Cp, are the pressure coefficientson the lower and uppersurface, respectively. 3. (20marks) A micro air vehicle,that is a very small aircraft, span of order 0.Im, is being designed.Figure 3 shows plots of the distributionof the Pohlhausen pressure-gradient parameter, A: (p52/p)(dUe/dx), versus x/c , alongthe suction surfaceof the airfoil section being considered for the aircraft, for various anglesof attack, a . These distributions were calculated using inviscid predictions for Ue and the Pohlhausen methodfor laminarboundary layers. Figure4 showsPohlhausen boundary-layer velocity profiles for variousvaluesof A. For each o,value state if flow separationis to be expected and, if so, at approximately what x/c value. Briefly explain the basisof your answers. On the blank graph, Figure 5, sketch as accuratelyas you can with the given information and your knowledge of airfoil behaviour, the lift and drag coeffrcients versusa . The lift is zero at cr : 0o. HAND IN this graph, being sure to write your name on it. What justification might the designers havefor assuming that laminarflow prevailsin this case? Z. (25 marks) The sketch, Fig.2, shows the camberline of a thin airfoil. It consists of three straight-line segments whose equations are asfollows: y = 4(Mc)x y: Hc y :Z(r/c)(c-x) for 0< xlc < 0.25 for 0.25 < x/c < 0.5 for 0.5 < x/c < I a) b) c) d) a) b) c)

AERO | 4302 | Aerodynamics and Heat Transfer | exam | #rnL CARLETON IINTVERSITY FINA

AERO | 4300 | Acoustics and Noise Control | exam | 

v :56 ffi Carleton tz uNlvERstry DURATION: 3 HOURS Department Name & Course Number: Courselnstructor(s): FINAL EXAMINATION December 2005 No.of Students: 65 Mechanical & Aerospace Bngineering AERO 4302 -MECH 5000 M.I. Yaras Students MUST count thenumber of pases in $riseraminauon question paper o"6E[6ffiii!'i] write, and report any discrepancy immediately to a proctor. This question paper has 4 pages. This examination question MAy be taken from the examination room. Ari ;wer all 4 questions. They are of equal value. A ceiling fan consists of five blades of 0.8m lengthand 0.lm width, which rotateat 100rpm. Estimate the torque needed to overcome the friction on the blades if they can be approximated to act as flat plates(p:1.2 kdrnr, v:l.5xl0-5 m2ls;. An unsteady, irrotational flow of constant density, p, is established between two parallel flat plates, separated by a distance h(t) that varieswith time, t. As shownin the figure, the upper plate (y: h(t)) moves vertically up or down, but remains parallelto the lower plate located aty:0. The stream function describing this flow is saidto be: ldh d lnh V=-;;xl=-----x! hdt dt a) Derive expressions for the velocity components u and v. b) Provethat this stream functionwill satisfu the velocity conditions on the surf-aces of the two plates. c) Derive an expression for the pressure difference between anypoint (x,y)in the fluid andthe point x:0, y:0. open books and notes,calculator (statiomry,) r! /t4/ / J'el AERO 4302 /MECH 5OOO FinalExamination December 2005 A laminar boundary-layer velocity profire is approximated by Y:r(z\-( z\' u \d/ \.r/ where u is the boundary-layer edgevelocity, and does not vary in the streamwise direction. a) Show that this profile satisfies the appropriate boundary conditions. b) Use the momentumintegralequation to determine the boundary-layer thickness, d, as a functionof streamwise location,.r. 4' Two immiscible liquids A and B are flowing steadily and in laminarstate down an inclined surface- A two-dimensional boundary layer develops on the surfaceand grows to approach the free surface. Derive the momentumintegral equationfor this boundary layer. ,sj v =.4 AERO 4302 IMECH 5OOO Final Examination December 2005 The following three questions areto be answered only by students registeredin MECH 5000. The students are to work on these questions independently during the 24-hour period following the 3-hour in-classexamination, and submit their answers to the course instructor by l0 p.m. on Dec.20 (location: 3l35ME). ,.. The questions areof equal value,and will constitute 30% of the final--exam mark for the students registered in MECH 5000. 5. The figure below illustrates a two-dimensional jet entering a reservoir which contains stationary fluid- A solution is soughtto the laminar boundary-layer equationsfor this situation- Assuming that there is no pressure gradientalong the jet, we are looking for a similarity solution for the stream functionof the following form: v6, y):6avxt't f (rt) where rl=s+ x''' In the above expressions, cr is a dimensional constant and v is the kinematic viscosity of the fluid. Confirm the validity of this sireamfunction. Derive the differential equation for the function f(q) and the boundary conditions which haveto be satisfied. lct cntcria. r Ercar

AERO | 4302 | Aerodynamics and Heat Transfer | exam | v :56 ffi Carleton tz uNlvERst

Exam-AERO4306-2005December.pdf-D,f. ~ Mechanical & Aerospace Engineering

I I I -uv CARLETON UNIVERSITY FINAL EXAMINATION April2002 DURATION: 3 HoURS for Eng. 87.438 students 4 uouRs for Ens. 88.511 students No. of Students: 41 Department Name & Course Number: Mechanical & Aerospace Engineering87.438/88.511 Instructor(s) Professor R.J. Kind HORZEDMEMORANDA Book, Calculators allowed Students MUST countthe number of pages in this examination question paper before beginning to write, and report any discrepancy immediately to a proctor. This question paper has 7 pages. This examination question paperMAY be takenfrom the examination room. In addition to this question paper. students require: an examination booklet yes X no _ a Scantron sheet yes no X Note l: Use the same symbolsand sign conventions as in the lecture notes;this practice has beenfollowed in this exam paper. Note 2: Attempt all parts of all questions; most parts can be done independently of precedingparts. l. (10 marks) (a) Explain in your oun words (10 lines or less)why'it is advantageous to usethe areodynmaic centre ratherthat the centre of pressure in representing the forcesand moments on lifting surfaces in stability and control analyses. (b) Does deflectionof the elevator or rudderaffect staticstabilitv of an aircraft? F'vnlqin your answer in 5 linesor less. 2. (10 marks) Using a derivation similarto that used in class, derive the expression for the y- acceleration of an aircraft in terms of body-fixed l.ariables. showingthat if p ; 0 and r ; 0 second order terms ur and -wp appear.Use suitable sketches to support your derivation. ,(b Engineering 87.438/88.5 1 1 Final Exam April2002 3. (25marks) A turboprop drivenprimarytrainer aircraft hasthe following characteristics: Mass: 1600 kg Power: 300kw wing: wing area16.7 m2 wingspan 10.2 m mean chord, c : 1.64 m aspect ratro 6.23 rving-body: \*-- 4.7 perradian: 0.082 perdegree C^, : -0.020 I'rac *'b aerodynamic centre0.235 c aft of leading edge horizontal tail: tail area1.9m2 sl"mmetric section; tail aerodynamic centre 7.7 m aft of wing leadingedge C., : 0.076o, + 0.05-5 5. (cr,, 6. in degrees) e: 0.57 oob at tail; o,*o is measured from the zero-liftdirection of the wine-bodv. a) The aircraft has a stick-fixedstaticmargin (h - h") of -0.15 (stable) and is flying at a speed of 280 km,hr at an altitude wherethe densityis 0.93 kg/m3. Determine the trim angieof attack(in degrees relativeto the zero lift line of the aircraft),the pitch-stiffness derivative, Cro, and the pitching moment coefficient atzero lift, C\{0,atthese conditions. what must the centre of grai'it_l' position be (in m aft of the wing leadingedge) for the conditions of part (a)? what change in elevator angle, 6., from the vaiue of part (a) would be required for equilibrium level flight at a speed of 190km/h if altitude and all other conditionsare as in part (a)? You may assume that the centreof gravity is 0.46 m aft of the rving leading edge andthat Cro : -0.0129 per degree. b) .l

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