/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 10 The velocity for a steady, incom... [FREE SOLUTION] | 91Ó°ÊÓ

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The velocity for a steady, incompressible flow in the \(x y\) plane is given by \(\vec{V}=i A / x+i A y / x^{2},\) where \(A=2 \mathrm{m}^{2} / \mathrm{s},\) and the coordinates are measured in meters. Obtain an equation for the streamline that passes through the point \((x, y)=\) (1,3). Calculate the time required for a fluid particle to move from \(x=1 \mathrm{m}\) to \(x=2 \mathrm{m}\) in this flow field.

Short Answer

Expert verified
The equation for the streamline passing through the point (1, 3) is \(y = e^{x-C}\) where C is a constant determined by the given point. The time required for the fluid particle to move from \(x=1 m\) to \(x=2 m\) is the definite integral from 1 to 2 of \(1/V_x dx\).

Step by step solution

01

Streamline Calculation

Streamline is the path a massless fluid particle would take in the flow. For 2D steady flow, the streamline is obtained by integrating the fluid velocity vector. That is, \(\frac{dy}{dx} = \frac{V_{y}}{V_{x}}\) where \(V_{x}\) and \(V_{y}\) are the x and y components of velocity. Substituting given values, we get \(\frac{dy}{dx} = \frac{A y}{A} = y\). The differential equation \(\frac{dy}{dx} = y\) can be solved via separation of variables method.
02

Solving the Differential Equation and Substituting the Boundary Condition

First, separate the variables on two sides. It gives us \(\frac{dy}{y} = dx\). Now, integrate both sides. We get \(\ln|y| = x + C\), where C is the constant of integration. Since the streamline passes through the point (1, 3), we substitute these values into the equation, i.e., \(\ln|3| = 1 + C\). Solving this gives us value of C. Substituting the value of C in the streamline equation will provide the required streamline.
03

Calculation for Time

The time required for a fluid particle to move from x = 1 m to x = 2 m is given by \(\int_{1}^{2} \frac{1}{V_x} dx \). Here \(V_x = A/x\) (component of velocity along x-axis). Substituting the value and integrating will give us the time taken for the fluid particle to move from x = 1 m to x = 2 m.

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Most popular questions from this chapter

A flow is described by velocity field \(\vec{V}=a y^{2} \hat{i}+b j\) where \(a=1 \mathrm{m}^{-1} \mathrm{s}^{-1}\) and \(b=2 \mathrm{m} / \mathrm{s}\). Coordinates are measured in meters. Obtain the equation for the streamline passing through point \((6,6) .\) At \(t=1 \mathrm{s}\), what are the coordinates of the particle that passed through point (1,4) at \(t=0 ?\) At \(t=3 \mathrm{s},\) what are the coordinates of the particle that passed through point (-3,0) 2 s earlier? Show that pathlines, streamlines, and streaklines for this flow coincide.

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Consider the flow ficld \(\vec{V}=a x t \hat{i}+b \tilde{j},\) where \(a=1 / 4 s^{-2}\) and \(b=1 / 3 \mathrm{m} / \mathrm{s}\). Coordinates are measured in meters. For the particle that passes through the point \((x, y)=(1,2)\) at the instant \(t=0,\) plot the pathline during the time interval from \(t=0\) to 3 s. Compare this pathline with the streakline through the same point at the instant \(t=3\) s.

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