Express continuity equation for steady two-dimensional flow with constant properties, and explain what each term represents.

Short Answer

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Answer: The continuity equation for steady two-dimensional flow with constant properties is \(\frac{\partial u}{\partial x} + \frac{\partial v}{\partial y} = 0\), where: 1. \(\frac{\partial u}{\partial x}\): Represents the rate of change of the fluid's velocity component in the x-direction with respect to the x-coordinate, defining the rate at which the fluid is accelerating or decelerating in the x-direction. 2. \(\frac{\partial v}{\partial y}\): Represents the rate of change of the fluid's velocity component in the y-direction with respect to the y-coordinate, defining the rate at which the fluid is accelerating or decelerating in the y-direction. The sum of these two terms is zero, which ensures the conservation of mass in the fluid flow.

Step by step solution

01

Express the continuity equation for two-dimensional flow

The continuity equation for two-dimensional flow can be written as: \(\frac{\partial(\rho u)}{\partial x} + \frac{\partial(\rho v)}{\partial y} = 0\) Where \(\rho\) represents the density of the fluid, \(u\) and \(v\) are the components of the fluid velocity vector in the x and y directions, respectively, and x and y are the spatial dimensions.
02

Identify the steady flow condition

For a steady flow, the flow properties like density and velocity do not change with time. Mathematically, this can be expressed as: \(\frac{\partial(\rho)}{\partial t} = 0\) and \(\frac{\partial(u)}{\partial t} =\frac{\partial(v)}{\partial t} = 0\) Since the given exercise states that we have a steady two-dimensional flow, we can incorporate the steady flow condition into the continuity equation.
03

Express the continuity equation for steady two-dimensional flow with constant properties

Given the steady flow condition and the two-dimensional continuity equation, we can now express the continuity equation for steady two-dimensional flow with constant properties as follows: \(\frac{\partial u}{\partial x} + \frac{\partial v}{\partial y} = 0\)
04

Explain each term in the continuity equation

In the continuity equation for steady two-dimensional flow with constant properties, the terms represent: 1. \(\frac{\partial u}{\partial x}\): This term represents the rate of change of the fluid's velocity component in the x-direction with respect to the x-coordinate. It defines the rate at which the fluid is accelerating or decelerating in the x-direction. 2. \(\frac{\partial v}{\partial y}\): This term represents the rate of change of the fluid's velocity component in the y-direction with respect to the y-coordinate. It defines the rate at which the fluid is accelerating or decelerating in the y-direction. The continuity equation states that the sum of these two terms is zero, which means that the mass of the fluid is conserved as it flows in a two-dimensional plane at a steady flow with constant properties.

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