If the flow of fluid in one direction only, which is called one dimensional flow (i.e. mostly flows in x-direction). Option D is correct.
Badrul said:
(Oct 6, 2013)
Stream line of flow must be strieght line so answer is D.
Nanu Dayma said:
(Oct 29, 2013)
B answer because of flow of fluid is one direction so its diagram is straight pv constant.
Sabir Khan said:
(Nov 7, 2013)
It should be in a straight line, otherwise there will be two component of velocity resulting 2d flow.
Bkrish said:
(Jan 1, 2014)
For one dimensional flow, the velocity is the function of single coordinate (i.e) u= f(x).
Let u be the velocity.
The function u = f(x) is the straight line.
Therefore one dimensional flow is the straight line flow.
Manik said:
(Feb 1, 2014)
I think answer is D because one dimensional flow means heat flows in only one direction.
Waseem Iqbal said:
(Apr 22, 2014)
One dimensional means which only changes w.r.t one space coordinates means it only depends on one coordinate.
Waseem Iqbal said:
(Apr 22, 2014)
Dear @Arun you are wrong.
One dimension does not mean like only in one space coordinates direction(as you say in x).
The direction may change from x to y coordinate direction but it is single.
Deepak said:
(Dec 18, 2014)
A flow in which the streamlines of its moving particles are represent by straight line is called one dimensional flow.
Bidur said:
(Dec 18, 2014)
Answer is D because straight line does not mean that it is flowing only in one direction.
Surender said:
(Mar 17, 2015)
1 D flow takes place in one direction only. So the correct answer is D.
Zxcv said:
(Apr 18, 2015)
The single space coordinate is usually the distance measured along the center-line (not necessarily straight) in which the fluid is flowing.
Example: The flow in a pipe is considered one-dimensional when variations of pressure and velocity occur along the length of the pipe, but any variation over the cross-section is assumed negligible.
In reality, flow is never one-dimensional because viscosity causes the velocity to decrease to zero at the solid boundaries.
Kapelemera said:
(Apr 23, 2015)
It is because the motion is translation and rotational.
Rahul Kumar said:
(Jul 4, 2015)
If pressure and velocity vary in one dimensional flow then pv remained constant as it graph shows. The straight line from origin. Usually fluid flowing in a pipe considered one dimensional flow. I hope it's something which make you understand.
Rajeev said:
(Jul 21, 2015)
I think both the option B and D are correct.
Rajesh said:
(Aug 25, 2015)
Answer B & D are correct because as it indicates one dimensional flow.
Jeevaa said:
(Aug 31, 2015)
Which one is correct B or D?
Prateek said:
(Sep 11, 2015)
1-D flow doesn't necessarily mean in a straight line, so answer should be D.
Vaibhav Bhagat said:
(Sep 16, 2015)
Both B & D correct because it is straight and flow in only 1 direction either x y or z.
Radha Choudhary said:
(Sep 18, 2015)
Both Option B & D are correct because it is indicates 1 dimensional flow.
Mahesh said:
(Mar 9, 2016)
Proper answer is D because if we think as straight line by considering u=f(x), it may have two components with respect to a reference point it means it represent 2d flow. So answer is D.
Nitish said:
(Jul 7, 2016)
It is either straight or one dimensional.
Rani Kokare said:
(Jul 25, 2016)
The flow is flow in the direction of ''x'' co-ordinate. It flow contain only 'x'co-ordinate.
Djarma said:
(Oct 10, 2016)
Please tell me the correct answer.
Sandy said:
(Nov 25, 2016)
ANS IS D ONLY.
Straight line is a 2d dimension.
Er. Harshit Mangla said:
(Dec 14, 2016)
One-dimensional flow.
All the flow parameters may be expressed as functions of time and one space coordinate only.
The single space coordinate is usually the distance measured along the centre-line (not necessarily straight) in which the fluid is flowing.
Example: the flow in a pipe is considered one-dimensional when variations of pressure and velocity occur along the length of the pipe, but any variation over the cross-section is assumed negligible.
In reality, flow is never one-dimensional because viscosity causes the velocity to decrease to zero at the solid boundaries.
If however, the non-uniformity of the actual flow is not too great, valuable results may often be obtained from a "one-dimensional analysis".
The average values of the flow parameters at any given section (perpendicular to the flow) are assumed to be applied to the entire flow at that section.
Neel K said:
(Mar 21, 2017)
One dimension means there is no turbulent flow.
Sharique said:
(Jun 27, 2017)
Answer will be D.
Ashish Baranwal said:
(Aug 10, 2017)
One dimensional flow mean the flow which is in a straight line.
Answer B is correct.
Shubham Khatri said:
(Aug 25, 2017)
Both B & D are correct as if the flow is one dimensional it will flow in a straight line. As one dimension always represents a single coordinate, i.e., U=f(x) if we consider flow along the x direction. But this explanation follows option D too as if the flow is considered along line x=y then with respect to the coordinate system which is tilted by 45 degrees it is a flow along the axis and hence again in a straight line.
So the velocity will be given as U=f(x') where x' would be the x direction in transformed axis and hence flow in a single direction is also a one-dimensional flow.
Kaushik said:
(Sep 21, 2017)
Option B is not correct because flow in a straight line is called laminar flow.
Option D is correct.
Xyz said:
(Oct 12, 2017)
B, right because we considered fluid is non viscous in nature and PV graphs show straight line, PV ' constant.
Aman said:
(Apr 16, 2018)
No, the One-dimensional flow has nothing to do with the straight line or curve. If the entire flow parameter requires only 1 independent variable to completely specify the flow then it is called one dimensional.
Utkarsh Saxena said:
(May 2, 2018)
I agree @Aman.
The one-dimensional flow does not necessarily mean a straight line.
Suppose an ant is moving in a zig-zag path. If we look at the path of an ant from above we will observe ant is moving in a zig-zag path which is lying on a 2d plane but if you ask the ant what is the path of your motion? The ant will definitely say that I am is moving in a straight line. Because ant will not be able to observe its motion from above. As soon as the ant takes turns on its path its X coordinate will also take a turn with it (ant). So if you are moving in a zig-zag path you can not say that you are moving in 2d. It will be ond D only.
Utkarhs Saxena said:
(May 2, 2018)
Option D is correct. Option B is the subset of option D. Because a Straight Line path and a zig-zag path both can be one Dimension.
