B. Tech in Aerospace Engineering
Dear Student,
As we explained in the Programme Guide for B. Tech in Aerospace Engineering, you will have to do one Tutor Marked Assignment (TMA) for each course.
You will find that the questions in the Assignments are analytical and descriptive so that you can better understand and comprehend the concepts.
Before you attempt the Assignments, please read the instructions carefully provided in the Programme Guide. It is important that you write the answer to all the TMA questions in your own words. Your answers should be in brief and to the point. Remember, writing answers to assignment questions will improve your writing skills and prepare you for the term-end examination.
You are to submit the assignments to the Coordinator of your Centre. You must obtain a receipt from the Centre for the Assignments submitted and retain it with you. It is desirable to keep a photocopy of the assignments submitted by you.
Once evaluated, the Centre will return the assignments to you. Please insist on this. The Centre will send the marks to the SR&E Division at IGNOU, New Delhi.
Submission
You need to submit the Assignments within the stipulated date for being eligible to appear in the term-end examination.
All Assignments are to be submitted by 30th November, 2010 to the Coordinator of the Centre allotted to you.
GUIDELINES FOR SUBMITTING THE ASSIGNMENTS
We expect you to answer each question as per instructions in the assignment. You will find it useful to keep the following points in mind :
Planning
Read the assignment carefully; go through the Units on which they are based. Make some points regarding each question and then rearrange them in a logical order.
Organisation
Be a little selective and analytical before drawing up a rough outline of your answer. Give adequate attention to question’s introduction and conclusion.
Make sure that
(a)The answer is logical and coherent.
(b)It has clear connections between sentences and paragraphs.
(c)The presentation is correct in your own expression and style.
Presentation
Once you are satisfied with your answer, you can write down the final version for submission. It is mandatory to write the assignment neatly in your own handwriting. If you so desire, you may underline the points you wish to emphasize. Make sure that the answer is within the stipulated word limit.
Prof. Subasis Maji
(Programme Coordinator)
Q.1(a)Explain the Air Traffic Management System Functional Structure.
(b)Describe the Separation Assurance Loop of the ATM System.
(c)What is DME? Explain its working with the help of a neat sketch
(d)What are marker beacons?
Q.2(a)With the help of neat diagrams, explain the Aircraft Monitoring System (AMS).
(b)With the help of neat sketch, explain the different types of Display’s in a RADAR System.
(c)What is an ATC Transponder? What are the different modes of operation of the transponder? What is the importance of the mode C?
Q.3(a)Define the Moudulation. Explain each type of Modulation.
(b)What is the difference between en-route navigation and terminal area Navigation?Explain any one type of en-route navigation system.
(c)What are PSR and SSR ? Where are they used?
Q.4(a)What do the following Acronym’s stand for? Explain each:
(i)ICAO,
(ii)ATM, and
(iii)ADF.
(b)What is Hyperbolic navigation? What are its types? Explain each type in detail
Q.5(a)Explain the specific hazards that an Airport may encounter. Also explain preventive measures.
(b)What are the steps, the pilot must take to ensure safety of passenger’s and crew, when he encounter engine failure after take off while flying a single engine aircraft?
(c)What is radio navigation?
Q.6(a)What are Network Protocols? Explain in brief.
(b)Explain the CW RADAR Principle and it’s working . Also expalin the FMCW RADAR.
(c)Describe the Analog Communication and Digital Communication with the help of a neat sketch.
Q.7(a)What are Kepler’s three law’s? Explain each law and hence expalin Geostationary orbit and derive related expressions.
(b)“Role of a Air Traffic Controller is vital in assisting the Pilot while taking off and landing off an aircraft” – comment.
(c)What are the different displays fitted in the aircraft. Briefly explain Head up display with suitable diagram.
(d)What are Air data instruments? Explain any three.
Q.8(a)Explain in short the following:
(i)GPS,
(ii)VOR,
(iii)ILS,
(iv)LORAN, and
(v)NDB.
(b)Explain the Principle of RADAR and derive the Radar equation.
(c)Differentiate between the Primary Surveillance Radar and Secondary Surveillance Radar.
Q.9(a)What are the day-to-day problem’s faced by the Air traffic control sustem?
(b)Explain the following term’s
(i)JATO,
(ii)EMALS, and
(iii)STCA.
(c)Explain the following Organization
(i)DGCA, and
(ii)AAI.
Q.10(a)What are the objectives of Surveillance System?
(b)Explain the system Parameter’s of any Radio Navigation System.
(c)If the Max range of a Radar is 750 kM. Find the pulse width when PP is 80 K watts and AV. Power is 32 watts.
Q.1(a)A 3 m solid rectangular bar of cross-section 10 mm x 15 mm is subjected to a compressive force of 150 kN. What is the change in length of the bar? Also find the strain and stress produced in the bar. Take E = 2 105 N/mm2.
(b)A composite bar made of brass and steel is fixed between two supports as shown in Figure 1. If the temperature is increased by 80oC, find the stresses induced in the steel and the brass section assuming (i) if the supports do not yield and (ii) if the supports yield by 0.15 mm.
Steel BarBrass Bar
Figure 1
Q.2(a) At a point in a material, there is a horizontal tensile stress of 270 MPa, a vertical tensile stress of 130 MPa and shearing stress of 40 MPa downwards on left. With the aid of Mohr’s circle or otherwise, find out the maximum and the minimum principal stresses and the planes on which they act. Determine also the maximum shearing stress in magnitude and direction.
(b)In a strained material, the state of stress at a point is given below:
, and
Find the following parameters:
(i)Principal stresses on two mutually perpendicular planes at the point,
(ii)Maximum shear stress,
(iii)Principal stress planes,
(iv)Planes of maximum shear stress, and
(v)Normal stress and shear stress on the planes of maximum shear stress.
Q.3(a)A composite bar is fixed between two supports as shown in Figure 2. If the temperature of the bar is raised from 25oC to 75oC find the stresses induced in each rod by assuming (i) if the supports do not yield, and (ii) if the supports yield by 0.25 mm.
Figure 2
(b)At a certain point within a strained material, the two normal stresses acting on two mutually perpendicular planes are 60 MPa tensile and 30 MPa compressive. The maximum principal stress is limited to 100 MPa. Find the shear stress on the planes. Also find the maximum shear stress at the point.
Q.4(a)Draw shear force and bending moment diagrams for the beam as shown in Figure 3.
Figure 3
(b)Draw shear force and bending moment diagrams for the beam as shown in Figure 4.
Figure 4
Q.5(a)A simple steel beam of 4 m span carries a uniformly distributed load of 6 kN/m over its entire span at a point load 2 kN at its centre. If the permissible stress does not exceed 100 MPa, find the cross-section of the beam assuming depth to be twice of breadth.
(b)A 2 m simple beam having cross-section 150 mm x 500 mm carries a point load of 20 kN at a distance of 0.5 m from the left end. Find the slope at the two ends, deflection under the load and the maximum deflection. TakeE = 2 104 N/mm2.
Q.6(a)Find the centroid of the shaded area formed by a straight line y = mx and acurve y =kx2 as shown in Figure 5, using direct integration method.
Figure 5
(b)Find the centroid and the area moment of inertia of the I-section as shown in Figure 6 about its centroidal axes.
Figure 6
Q.7(a)A 5 m cantilever beam of cross-section 150 mm x 300 mm weighing 0.05 kN/m carries an upward concentrated load of 30 kN at its free end as shown in Figure 7. Determine the maximum bending stress at a Section 2 m from free end.
Figure 7
(b)An I-section beam as shown in Figure 8 is subjected to a shear force 50 kN. Find the magnitude and position of maximum shear stress.
Figure 8
Q.8(a)Two point loads of 5 kN and 15 kN are acting on a 5 m simple beam at 1 m and 2 m respectively from the left end. Find
(i)Slopes at the two ends,
(ii)Deflections under the applied loads, and
(iii)Positions and magnitude of maximum deflection.
TakeE = 90 GPa
I = 18 106 mm4
(b)Find the lowest speed at which 250 kW could be transmitted through a shaft of diameter 63 mm. The maximum shear stress is limited to 50 MPa. If length of the shaft is 6 m, find the angle of twist. Take G = 80 GPa
Q.9(a)Find the maximum torque that can be applied safely to a shaft of a diameter 300 mm. The permissible angle of twist is 1.5o in a length of 7.5 m and maximum shear is limited to 42 MPa. Take G = 84.4 GPa.
(b)A close coiled helical spring of mean coil radius equal of 6 times the wirediameter is subjected to an axial load of 120 N. It can absorb 5 J of energy producing a deflection of 50 mm. The maximum stress in the spring is not to exceed 80 N/mm2. Find the mean coil diameter, the wire diameter, the number of turns in the spring and the length of the spring. Take G = 80 kN/mm2.
Q10(a)A bar of length 2 m is subjected to an axial load of 25 kN. The diameter of the bar for one-half of its length is 30 mm and for the other half 60 mm. Calculate the strain energy stored in the bar. Take E = 200 GPa.
(b)A thin cylinder of inside diameter 250 mm is made of steel plate of thickness 12 mm and having yield strength of 390 MPa. Find the maximum fluid pressure assuming a factor of safety of 2.5 on the maximum shear stress.
Q.1(a)State how the properties of alloy steels are affected by following alloying elements: manganese, chromium, and tungsten.
(b)List any two commonly used nonferrous alloys stating their composition and application.
Q.2(a)Draw a stress-strain diagram for a low carbon steel specimen indicating the proportional limit, elastic limit, yield point, the point of maximum loading and rupture. Explain the above important data.
(b)What are plastics? Name two broad classifications of plastics. Distinguish between them. Explain the term “polymerization”.
Q.3(a) (i)State briefly electroplating with its advantages and limitations. List important quantitative and qualtitaive properties of lubricants.
(ii)Why plastic coating is prefered on metals? State the various methods used in coating plastics.
(b)Draw the Iron-Carbon diagram and identify the following transformations.
(i) Peritectic Reaction
(ii)Eutectic Reaction
(iii)Eutectoid Reaction
Q.4(a)Show that the atomic packing factor for the FCC crystal structure is 0.74.
(b)With the help of sketches, discuss the fatigue crack propagation mechanism in (i) ductile material and (ii) brittle material.
Q.5(a)Determine the composition, in atom percent, of an alloy that consists of 97 wt% aluminum and 3 wt% copper.
(b)A cylindrical rod of copper (E = 110 GPa), having a yield srenght of 240 MPa is to be subjected to a load of 6660 N. If the lenght of the rod is 380 mm, what must be the diameter to allow an elongation of 0.50 mm?
Q.6(a)A steel specimen shows upper yeid point at 280 MPa, and lower yeild point at 250 MPa. If modulus of elasticity, E, for steel is 230 ×103 MPa, calculate modules of resilience.
(b)A piece of copper originally 305 mm long is pulled in tension with a strees of 276 MPa. If deformation is entirely elastic, what will be the resultant elongation? Take E for
copper = 11.0 104 MPa.
Q.7(a)A steel wire having y 190 MPa is required to have a modulus of resilience of
140 106 N-m/mm3. The yield strength can be increased by strain hardening. What should be the percentage increase in yield strength ? Take E = 210 Χ 103 N/mm2.
(b)In a Brinell hardness test, a 1500 kg load is pressed into a specimen using a 10 mm diameter hardened steel ball. The resulting indentation has a diameter = 3.2 mm. Determine the BHN for the metal.
Q.8(a)A cylindrical metal specimen 12.7 mm in diameter and 250 mm long is to be subjected to a tensile stress of 28 MPa; at this stress level the resulting deformation will be totally elastic.
(i)If the elongation must be less than 0.080 mm, which of the metals in Table 1 are suitable candidates? Why?
(ii)If, in addition, the maximum permissible diameter decrease is 1.2 x 10–3 mm, which of the metals in Table 1 may be used? Why?
Table 1 : Room Temperature Elastic and Shear Moduli,
and Poission’s Ratio for various Metal Alloys
(GPa) / Shear Modulus
(GPa) / Poisson’s Ratio
Aluminum / 69 / 25 / 0.33
Brass / 97 / 37 / 0.34
Copper / 110 / 46 / 0.34
Magnesium / 45 / 17 / 0.29
Nickel / 207 / 76 / 0.31
Steel / 207 / 83 / 0.30
Titanium / 107 / 45 / 0.34
Tungsten / 407 / 160 / 0.28
(b)A cylindrical metal specimen having an original diameter of 12.8 mm and gauge length of 50.80 mm is pulled in tension until fracture occurs. The diameter at the point of fracture is 6.60 mm, and the fractured gauge lenght is 72.14 mm. Calculate the ductility in terms of perent reduction in area and percent elongation.
Q.9(a)A large thin plate carrying a crack of 80 mm at its centre is subjected to fluctuating stress cycle perpendicular to crack. max = 90 MPa, and min = 40 MPa. The fracture toughness of material of plate is 1700 MPa .
(b)What are the functions of cutting fluids? Why are oil-water emulsions used as cutting fluids?
Q.10(a)A hypoeutectoid steel which was cooled slowly from austenite () state to roomtemperature was found to contain 10% eutectoid ferrite. Assume no change in structure occurred on cooling from just below the eutectoid temperature to room temperature. Calculate the carbon content of steel.
(b)A unidirectional FRP is produced with fibre volume ratio of 60%. The density of fibre is 1480 kg/m3. Determine the weight percentages of matrix and fibre and density of the composite. Also determine the modulus of elasticity of the composit if Ef = 70 MPa and
Em = 3 GPa.
Q.1(a)If the velocity distribution over a plate is given by where u is the velocity inm/s at distance y metres above the plate, determine the shear stress at a distance of 0.15 m from the plate. Take the dynamic viscosity of the fluid as 0.834 N s/m2.
(b)Calculate (i) the discharge and (ii) the power required to pump a liquid of specific gravity 0.8, viscosity 0.01 N s/m2 through a pipeline 2 cm diameter, 100 m long operating at Reynolds number of 500.
Q.2(a)A square plate of size 1 m 1 m and weighing 350 N slides down an inclined plane with a uniform velocity of 1.5 m/s. The inclined plane is laid on a slope of 5 vertical to
12 horizontal and has an oil film of 1 mm thickness. Calculate the dynamic viscosity of oil.
(b)Calculate the specific weight, density and specific gravity of two litres of liquid which weight 15 N.
Q.3(a)A wooden block of width 2 m, depth 1.5 m and length 4 m floats horizontally in water. Find the volume of water displaced and position of centre of buoyancy. The specific gravity of the wooden block is 0.7.
(b)Check if represents the velocity potential for 2-dimensional irrotational flow. If it represents, then determine the stream function .
Q.4(a)The velocity vector in a fluid flow is given by . Find the velocity and acceleration of a fluid particle at (1, 2, 3) at time, t = 1.
(b)A fluid flow field is given by . Prove that it is a case of possible steady incompressible fluid flow. Calculate the velocity and acceleration at the point (2, 1, 3).
Q.5(a)A pipe, through which water if flowing, is having diameters, 20 cm and 10 cm at the cross-sections 1 and 2 respectively. The velocity of water at section 1 is given 4.0 m/s. Find the velocity head at sections 1 and 2 and also rate of discharge.
(b)A 25 mm diameter nozzle discharges 0.76 m3 of water per minute when the head is
60 m. The diameter of the jet is 22.5 mm. Determine: (i) the values of co-efficients Cc, Cv and Cdand (ii) the loss of head due to fluid resistance.
Q.6(a)A pipe line of 0.6 m diameter is 1.5 km long. In order to augment the discharge, another line of the same diameter is introduced parallel to the first in the second half of the length. Neglecting minor losses, find the increase in discharge if f = 0.04. The head at inlet is
30 m.
(b)A pipeline conveys 0.00833 m3/s water from an overhead tank to a building. The pipe is 2 km long and 0.15 m diameter; f = 0.03. It is desired to increase the discharge by 30% by installing another pipeline in parallel with this over half the length. Suggest a suitable diameter of the pipe to be installed. Is there an upper limit on discharge augmentation by this arrangement?
Q.7(a)A pipe (1) 450 mm in diameter branches into two pipes (2) and (3) of diameters 300 mm and 200 mm respectively as shown in Figure 1. If the average velocity in 450 mm diameter pipe is 3 m/s, find:
(i)discharge through 450 mm diameter pipe and
(ii)velocity in 200 mm diameter pipe if the average velocity in 300 mm pipe is
2.5 m/s.
Figure 1
(b)If for a two-dimensional potential flow, the velocity potential is given by : , determine the velocity at the point (2, 3). Determine also the value of stream function at the point (2, 3).
Q.8(a)Calculate: (i) the pressure gradient along flow, (ii) the average vleocity, and (iii) the discharge for an oil of viscosity 0.02 Ns/m2 flowing between two stationary parallel plates 1 m wide maintained 10 mm apart. The velocity midway between the plates is 2 m/s.
(b)Glycerine of density 1250 kg/m3 and viscosity 0.72 kg/ms flows through a pipe of 80 mm diameter. If the shear stress at the wall is 300 N/m2, calculate the following:
(i)the pressure gradient along the flow, (ii) the average velocity in the pipe,
(iii)the rate of discharge, and (iv) the Reynolds number of the flow.
Q.9(a)A partially submerged body is towed in water. The resistacne R to its motion depends on the density , the viscosity of water, length L of the body, velocity V of the body and the acceleration due to gravity g. Show that the resistance to the motion can be expressed in the form
(b)An agitator of diameter D rotates at a speed N in a liquid of density and viscosity . Show that the power P required to mix the liquid is expressed by a functional form,
Q.10(a)A flat plate, 1.5 m 1.5 m, moves at 50 km/hr in a stationary air of density 1.15 kg/m3.
If the coeffcients of drag and lift are 0.15 and 0.75 respectively, determine
(i)the lift force,(ii)the drag force,
(iii)the resultant force and(iv)the power required to keep the plate in motion.
(b)The laminar boundary layer profile in a case is approximated by a cubic parabola
where u = velocity at a distance y from the surface and . Calculate the displacement thickness and momentum thickness in terms of and work out the shear stress at the surface.