Midterm Flashcards
In turbulent pipe liquid flow, zero velocity at the tube wall and a parabolic velocity distribution.
False
Pipe flows with Re number less than 6000 are inherently laminar
false
Pipe flows with Re number more than 4000 are mostly turbulent but it might be laminar in few cases
True
For the same liquid and pipe diameter, increasing flow rate leads to an increase in the Re number
True
For the same liquid and flow rate , increasing the pipe diameter leads to an decrease in the Re number
False
Drop in pressure of liquid flow in coarse pipe is higher than the drop of pressure in smooth pipe
True
In a water flowing pipeline, if the diameter of a pipe is reduced, the pressure drop in the line per unit length will decrease
False
friction factor in a liquid flow in a pipe decreases with decreasing Re number
false
For the same pipe and liquid , pressure drop decreases with the increase in the flow rate
false
Based on Moodys’ diagram shown below, Friction factor in a liquid flow in a pipe increases with decreasing relative roughness (D/e)
false
Based on Moody’s diagram shown below, Friction factor in a fully laminar liquid flow is:
inversely proportional to Re
The dynamic viscosity is calculated by measuring the terminal velocity (v) of a ball falling through a fluid
True
If a gravity acceleration is 9.822 m/s2 at standard sea level, then, the weight of 1kg-force is equal to 1 kg-mass
True
Hydrometer sinks deeper in liquid as the SG of the liquid increases
False
As fluid temperature increases, the density of the fluid increases.
False
Liquid water is assumed to be an incompressible fluid to simplify calculations.
True
Oil is slightly compressible fluid; therefore, it can not be considered as ideal fluid.
False
Small ceramic ball fall in oil at a lower velocity than falling a large ceramic ball.
True
Hydrostatic pressure is the pressure that is exerted by a liquid at equilibrium at a given point within the liquid, due to the force of gravity; it depends on density of liquid, gravity acceleration, and the vertical depth form the surface of the liquid (P =pgh).
True
Terminal velocity of falling ball in oil decreases with increasing oil temperature.
False
The direction of pressure is always perpendicular to surface area of a body emerged inside fluids.
True
The peizometric head is what is measured with the manometer board on the apparatus for lab 3 experiment
True
The energy loss for the rotameter decreases with increasing the liquid flow rate
True
Venturi flowmeter can’t be used in pipes having small diameter
True
The energy loss associated with the orifice meter is small.
False
The energy loss for the rotameter is seen to be approximately constant irrespective of flow rate
True
The discharge coefficient of the orifice flow meter is low.
True
The venturi tube is suitable for clean liquid but not for dirty and viscous liquid.
False
From the following identify which flowmeter requires to be mounted vertically?
Rotameter
Small ceramic ball fall in oil at a higher velocity than falling a large ceramic ball
False
If the temperature of the liquid decreases, its viscosity will increase causing the balls to
travel through the liquid faster.
False
Based on Moody’s diagram shown below, friction factor in a transition liquid flow in a pipe decreases with decreasing Reynolds.
False
Based on Moody’s diagram shown below, Friction factor in a liquid flow in a pipe increases with increasing relative roughness
True
Friction Losses in Pipes is constant for fully turbulent flow.
True
For laminar flow in a horizontal pipe, the friction factor decreases with increasing Reynolds number and independents on surface roughness.
False
Slow fluid flows are dominated by viscous forces.
True
In the Venturi flowmeter, viscosity effect is low
False
In the Orifice flowmeter, viscosity effect is low
False
The energy loss for the rotameter increases with increasing the liquid flow rate.
False
