8/13/2019 Me2204 Apr May11

http://slidepdf.com/reader/full/me2204-apr-may11 1/3

8/13/2019 Me2204 Apr May11

http://slidepdf.com/reader/full/me2204-apr-may11 2/3

114052

PART B — (5 × 16 = 80 marks)

11.  (a) Explain in detail the Newton's law of viscosity. Briefly classify the

fluids based on the density and viscosity. Give the limitations of

applicability of Newton's law of viscosity.

Or

(b) State the law of conservation of man and derive the equation of

continuity in Cartesian coordinates for an incompressible fluid.

Would it alter if the flow were unsteady, highly viscous and

compressible?

12.  (a) A lubricating oil flows in a 10 cm diameter pipe at 1 m/s. Determine

whether the flow is laminar or turbulent. For the lubricating oil2

/1.0   m Ns=µ    and  ρ = 930 kg/ m3. Calculate also transition and

turbulent velocities.

Or

(b) A smooth flat plate with a sharp leading edge is placed along a free

stream of water flowing at 3m/ s. Calculate the distance from the

leading edge and the boundary thickness where the transition from

laminar to turbulent- flow may commence. Assume the density of

water as 1000 kg/m3 and viscosity as 1 centipoise.

13.  (a) What is the significance and the role of the following parameters?

(i) Reynolds number

(ii) Froude number

(iii) Mach number

(iv) Weber number. (16)

Or

(b) An agitator of diameter D rotates at a speed N in a liquid of density

 ρ   and viscosity µ  . Show that the power required to mix the liquid is

expressed by a functional form

 

  

 =

 g 

 D N  ND f  

 D N 

 P  22

53,

µ 

 ρ 

 ρ . (16)

   2  

   1 

   9  

     

     

   2  

   1 

   9  

     

     

   2  

   1 

   9  

8/13/2019 Me2204 Apr May11

http://slidepdf.com/reader/full/me2204-apr-may11 3/3

114053

14.  (a) A gas turbine operates between 1000k and 650 k temperature limitstaking in air 20 kg/ s at 125 m/ s and discharging at 300 m3/ s.Estimate the power developed by the turbine. Given ../995   K  Kg  J C  p =  

Or

(b) Explain in detail about the performance curves for pumps andturbines.(16)

15.  (a) A single acting reciprocatory pump has a plunger of diameter 30 cmand stroke of 20 cm. If the speed of the pumps is 30 rpm and itdelivers to6.5 lit/ s of water, find the coefficient of discharge and the percentageslip of the pump.

Or

(b) Write briefly on the following.

(i) Rotary pumps and their classifications. (8)

(ii) Indicator diagram for reciprocating pump. (8)

———————

   2  

   1 

   9  

     

     

   2  

   1 

   9  

     

     

   2  

   1 

   9