YILDIZ Technical University
Department of Mechanical Engineering
Fluid Mechanics – Final- exam questions (G2)
No
Name, Surname
1- A 25‐mm‐diameter shaft is pulled through a cylindrical bearing as shown in Figure. The lubricant that fills the 0.3‐mm gap between the shaft and bearing is an oil having a kinematic viscosity of 8.0 10‐4 m2/s and a specific gravity of 0.91. Determine the force P required to pull the shaft at a velocity of 3 m/s. Assume the velocity distribution in the gap is linear. 0
,
8. 10
,
∗ 0.91 10 ∗ 3 ∗ 0.025 ∗ 0.5
0.0003
285.74
2- Water flows through a horizontal branching pipe as shown in Figure. Determine the pressure at section (3).
=0.1∙ 4
0.4
/ .
.
∙ .
0.4
∙ .
0.02 ∙ 10.78
0.07
10.78 / 2.63 / 2
11.01.2013
400
9.80
4
2 9.81
2.63
404.5
Prof. Dr. Ali PINARBAŞI
YILDIZ Technical University
Name, Surname
Department of Mechanical Engineering
Fluid Mechanics – Final- exam questions (G2)
No
3- AhorizontalpipehasanabruptexpansionfromD1=
8cmtoD2=16cm.Thewatervelocityinthesmaller
section is 10 m/s and the flow is turbulent. The
pressureinthesmallersectionisP1=300kPa.Taking
thekineticenergycorrectionfactortobe1.06atboth
the inlet and the outlet, determine the downstream
pressureP2?
11.01.2013
Prof. Dr. Ali PINARBAŞI