Define. i) Streamline flow ii) Turbulent flow Give significance of Reynold’s number.

1 Answer

Answer :

i) Streamline flow

The flow of liquid in which every particle of liquid moves in the same direction of flow of liquid is called streamline flow.

ii) Turbulent flow

The flow of liquid in which every particle is not moving in line and they move in random direction is called turbulent flow.

Significance :

(1) When R is less than 2000 liquid flow is streamline.

(2) When R is between 2000 to 3000 liquid flow is unstable.

(3)When R is greater than 3000 liquid flow is turbulent. 

Related questions

Description : Distinguish between streamline and turbulent flow of liquid. 

Last Answer : Stream line flow Turbulent flow The path of every particle is same  The path of every particle is different The velocity of particle is constant in magnitude and direction The velocity of particle at each point is ... . V < vc V > vc R < 2000 R > 3000

Description : A large Reynold number is indication of (A) Smooth and streamline flow (B) Laminar flow (C) Steady flow (D) Highly turbulent flow

Last Answer : Answer: Option D

Description : A flow in which the quantity of liquid flowing per second is not constant, is called (A) Streamline flow (B) Turbulent flow (C) Steady flow (D) Unsteady flow

Last Answer : Answer: Option D

Description : A flow in which each liquid particle has a definite path, and the paths of individual particles do not cross each other, is called (A) Steady flow (B) Uniform flow (C) Streamline flow (D) Turbulent flow

Last Answer : Answer: Option C

Description : A flow in which the quantity of liquid flowing per second is constant, is called __________ flow. (A) Steady (B) Streamline (C) Turbulent (D) Unsteady

Last Answer : Answer: Option A

Description : The flow in which each liquid particle has a definite path and their paths do not cross each other is called (A) One dimensional flow (B) Streamline flow (C) Steady flow (D) Turbulent flow

Last Answer : Answer: Option B

Description : Distinguish between streamline flow and turbulent flow.  

Last Answer : Stream line flow  Turbulent flow  The path of every particle is same The path of every particle is different  The velocity of particle is constant in magnitude and direction  The velocity of particle at each point ... V < vc V > vc R < 2000  R > 3000 

Description : The Sieder-Tate correlation for heat transfer in turbulent flow in pipe gives Nu α Re 0.8 , where, Nu is the Nusselt number and Re is the Reynolds number for the flow. Assuming that this relation is valid, the heat transfer co-efficient ... pipe diameter (D) as (A) D-1.8 (B) D-0.2 (C) D0.2 (D) D1.8

Last Answer : (B) D-0.2

Description : Critical value of the __________ number governs the transition from laminar to turbulent flow in free convection heat transfer. (A) Grashoff (B) Reynolds (C) Both 'a' & 'b' (D) Prandtl & Grashoff

Last Answer : (D) Prandtl & Grashoff

Description : The friction factor for turbulent flow in a hydraulically smooth pipe (A) Depends only on Reynolds number (B) Does not depend on Reynolds number (C) Depends on the roughness (D) None of these

Last Answer : (A) Depends only on Reynolds number

Description : When the pipe Reynold's number is 6000, the flow is generally (A) Viscous (B) Laminar (C) Turbulent (D) Transition

Last Answer : (C) Turbulent

Description : In turbulent flow, a rough pipe has the same friction factor as a smooth pipe (A) In the zone of complete turbulence (B) When the roughness projections are much smaller than the thickness of ... ) Everywhere in the transition zone (D) When the friction factor is independent of the Reynold's number

Last Answer : (B) When the roughness projections are much smaller than the thickness of the laminar film

Description : Pick out the wrong statement: (A) Greater is the kinematic viscosity of the liquid, greater is the thickness of the boundary layer (B) Blowers develop a maximum pressure of 2 atmospheres ( ... factor in case of turbulent flow of liquids in pipe depends upon relative roughness & Reynolds number

Last Answer : (C) Friction losses in pipe fittings are generally expressed in terms of velocity heads

Description : Isothermal turbulent flow of a fluid results in decrease of its pressure, which depends on the (A) Wall roughness (B) Reynolds number (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

Description : . In case of turbulent flow of fluid through a circular pipe, the (A) Mean flow velocity is about 0.5 times the maximum velocity (B) Velocity profile becomes flatter and flatter with ... , shear stresses, random orientation of fluid particles and slope of velocity profile at the wall are more

Last Answer : (D) Skin friction drag, shear stresses, random orientation of fluid particles and slope of velocity profile at the wall are more

Description : For the Stoke's law to be valid in the case of a falling sphere in a fluid, the (A) Reynolds number (based on sphere diameter) should be < 1 (B) Flow around the sphere should be in turbulent region (C) Sphere must be metallic (D) Fluid density should be constant

Last Answer : (C) Sphere must be metallic

Description : Nusselt number is related to the Reynolds number (Re) in turbulent & laminar flow respectively as (A) Re0.5, Re0.8 (B) Re0.8, Re-0.5 (C) Re0.8, Re0.5 (D) Re-0.8, Re0.5

Last Answer : (C) Re0.8, Re0.5

Description : For pipes, turbulent flow occurs when Reynolds number is (A) Less than 2000 (B) Between 2000 and 4000 (C) More than 4000 (D) Less than 4000

Last Answer : Answer: Option C

Description : Which of the fluid forces are not considered in the Reynold's equation of flow? (A) Viscous forces (B) Turbulent forces (C) Pressure forces (D) Compressibility forces

Last Answer : (D) Compressibility forces

Description : For turbulent mass transfer in pipes, the Sherwood number depends on the Reynolds number as (A) Re 0.33 (B) Re 0.53 (C) Re 0.83 (D) Re

Last Answer : (C) Re 0.83

Description : Transition from laminar to turbulent zone in free convection heat transfer is governed by the critical value of (A) Grashoff number (B) Grashoff number & Reynolds number (C) Reynolds number (D) Grashoff number & Prandtl number

Last Answer : Option D

Description : Define : (i) Laminar flow (ii) Turbulent flow

Last Answer : Laminar flow: - 1. Laminar flow occurs when the fluid flows in infinitesimal parallel layers with no disruption between them. For laminar flow Reynolds number Re < 2300 OR 2. The flow in which ... such a way that its velocity changes irregularly, such type of flow is known as turbulent flow. 

Description : Explain Reynold’s number with its equation and give significance.

Last Answer : The Reynolds number is defined as the ratio of inertia force to viscous force. Reynolds number is dimensionless number. It is used to determine the laminar or turbulent flow type. Significance : Using value of Reynold's number the type of flow can be identified.

Description : Define the term i) Ultimate stress ii) Factor of safety.

Last Answer : i) Ultimate Stress:- It is defined as the ratio of maximum load that the specimen (system) can withstand to original cross-sectional area of specimen.  ii) Factor of Safety:- It is defined as the ratio of ultimate stress to working stress.

Description : Define transverse wave. Give one example.

Last Answer : Transverse waves: The wave in which direction of vibration of particles of material medium is perpendicular to the direction of propagation of wave is called transverse wave. Example: Light wave, electromagnetic waves etc.

Description : Define simple harmonic motion. Give its two example. 

Last Answer : Simple harmonic motion: The to and fro motion of the object about its mean position is called simple harmonic motion.  Examples: motion of swing, motion of sewing machine , motion of clock pendulum , etc.

Description : Define capillarity. Give its any two examples.

Last Answer : Capillarity: - The rise or fall of a liquid inside the capillary is called as capillarity.  Examples (1) Oil rises up to the end of wick of lamp due to capillarity. (2) The water and minerals ... capillarity. (3) A blotting paper absorbs ink due to capillarity. (4) Rise of ink through pen nib.

Description : Define laminar flow and turbulent flow.

Last Answer : Laminar flow : When a fluid flowing through the pipe at different speeds (fast at center and slow at edges), and the fluid particles move in layers with one layer sliding over the adjacent ... successive cross sections, then this flow is called as turbulent flow. Reynolds no is greater than 4000 

Description : Compare i) Steady and uniform flow ii) Laminar and turbulent flow

Last Answer : Steady flow:- The flow is said to be steady when the flow characteristics, such as velocity, pressure, density and temperature do not change with time. Water flowing through a tap at a constant rate is an ... called as turbulent flow. e.g. The flow of river at the time of flood is turbulent flow.

Description : Define the principles of superposition of waves. 

Last Answer : Principle of superposition of wave: When two waves travelling through a medium arrive at a point simultaneously, each wave produces its own displacement at that point. The resultant displacement at that point is equal to the vector sum of the individual displacement of the two waves.

Description : Define the two specific heats of gas. 

Last Answer : Specific heat of a gas at constant volume - Specific heat of a gas at constant volume is defined as the amount of heat required to increase the temperature of unit mass of a gas by one degree at ... heat required to increase the temperature of unit mass of a gas by one degree at constant pressure. 

Description : Define velocity gradient and state its unit

Last Answer : Velocity Gradient: It is defined as the change in velocity per unit change in vertical distance of the layer from the fixed layer. Unit = per second OR 1/ sec

Description : Define compressibility. State its SI unit.

Last Answer : Compressibility: The reciprocal of bulk modulus of elasticity is called as compressibility. OR The property on account of which the body can be compressed by the application of external force is called compressibility. S.I. Unit:- m2/N 

Description : Define Cohesive force and Adhesive force 

Last Answer : i) Cohesive force: - It is the force of attraction between two molecules of same substance.  ii) Adhesive force: - It is the force of attraction between two molecules of different substance.

Description : Define amplitude and periodic time of a vibrating particle.

Last Answer : Amplitude (a):- The maximum displacement of particle from its mean position on either side is called amplitude.  Periodic time:- The time taken by a wave to complete one oscillation is called periodic time.

Description : Define isothermal and Adiabatic process.

Last Answer : Isothermal process:- The process in which volume of a gas changes keeping its temperature constant is called isothermal change.  Adiabatic process:- The process in which volume of a gas changes with change in temperature is called Adiabatic change. 

Description : Define specific heat of a gas at constant pressure and at constant volume.

Last Answer : Specific heat of a gas at constant volume:- Specific heat of a gas at constant volume is defined as the amount of heat required to increase the temperature of unit mass of a gas by one degree at ... heat required to increase the temperature of unit mass of a gas by one degree at constant pressure. 

Description : Define absolute zero temperature and one calorie

Last Answer : Absolute zero temperature:- The temperature at which both pressure and volume of gas become theoretically zero is called absolute zero temperature.  Calorie: The amount of heat is required to increase the temperature of 1gm of water by 10C is called calorie.

Description : Define surface tension. State its S.I. unit.

Last Answer : Definition:- The force acting per unit length of an imaginary line drawn to surface of liquid.  OR  The surface tension is defined as the property of liquids by virtue of which the surface of a liquid is ... due to the tendency to contract and occupy minimum surface area.  S.I. unit :- N/m

Description : State Hooke’s Law of elasticity. Define Elastic limit.

Last Answer : Hooke’s Law:- Within elastic limit, stress is directly proportional to strain.  Elastic limit: -It is the maximum value of the stress upto which the body shows elasticity.

Description : The force which opposes the relative motion between different layers of liquid or gases is called – (1) Critical Velocity (2) Streamline Flow (3) Terminal Velocity (4) Viscous Force

Last Answer : (4) Viscous Force Explanation: Critical Velocity – The maximum velocity upto which fluid motion is streamline is called Critical Velocity. Streamline Flow – If velocity of all fluid particles is same all the time then it can be said in streamline flow.

Description : In frictional fluid flow, the quantity, (P/ρ) + (V 2 /2gc) + gz/gc) is (A) Constant along a streamline (B) Not constant along a streamline (C) Increased in the direction of flow (D) None of these

Last Answer : (B) Not constant along a streamline

Description : The continuity equation in ideal fluid flow states that (A) Net rate of inflow into any small volume must be zero (B) Energy is not constant along a streamline (C) Energy is constant along a streamline (D) There exists a velocity potential

Last Answer : (A) Net rate of inflow into any small volume must be zero

Description : A streamline is (A) The line connecting the mid-points of flow cross-sections (B) Defined for uniform flow only (C) Drawn normal to the velocity vector at every point (D) Always the path of a particle

Last Answer : (C) Drawn normal to the velocity vector at every point

Description : If in a flow field, between any two points, then the flow must be (A) Steady, incompressible, irrotational (B) Steady, compressible, irrotational (C) Steady, compressible and along a streamline

Last Answer : (A) Steady, incompressible, irrotational

Description : Velocity at a certain point in case of streamline flow is (A) Constant (B) Independent of time (C) Both (A) & (B)

Last Answer : (C) Both (A) & (B)

Description : Pick out the wrong statement about a streamline. (A) It is always parallel to the main direction of the fluid flow (B) It is a line across which there is no flow and it is ... any two streamlines can be considered to be in isolation and the streamline spacing varies inversely as the velocity

Last Answer : (A) It is always parallel to the main direction of the fluid flow

Description : A streamline is a line in flow field, (A) That is traced by all the fluid particles passing through a given point (B) Along which a fluid particle travels (C) Such that at every point on it, the velocity is tangential to it (D) None of these

Last Answer : (C) Such that at every point on it, the velocity is tangential to it

Description : The ratio of maximum to average velocity in case of streamline flow between parallel plates is (A) 1 (B) 1.5 (C) 2 (D) 2.5

Last Answer : (B) 1.5

Description : __________ flow means the flow of incompressible fluid with no shear. (A) Potential (B) Streamline (C) Creep (D) Boundary layer

Last Answer : (A) Potential