Air at 40°C flow steadily through the pipe shown in Fig. 1 below. If P1 = 40 kPa (gage), P2 = 10 kPa (gage), D = 3d, Patm ≅ 100
1 answer:
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Answer:
Explanation: see attachment below
Answer:
Explanation:
We can assume that the general formula for the drag force is given by:
And we can see that is proportional to the area. On this case we can calculate the area with the product of the width and the height. And we can express the grad force like this:
Where w is the width and h the height.
The last formula is without consider the area of the carrier, but if we use the area for the carrier we got:
If we want to find the additional power added with the carrier we just need to take the difference between the multiplication of drag force by the velocity (assuming equal velocities for both cases) of the two cases, and we got:
We can assume the same drag coeeficient and we got:
1.7 ft =0.518 m
60 mph = 26.822 m/s
In order to find the drag coeffcient we ned to estimate the Reynolds number first like this:
And the value for the kinematic vicosity was obtained from the table of physical properties of the air under standard conditions.
Now we can find the aspect ratio like this:
And we can estimate the calue of from a figure.
And we can calculate the power difference like this:
Answer:
The statement regarding the mass rate of flow is mathematically represented as follows
Explanation:
A junction of 3 pipes with indicated mass rates of flow is indicated in the attached figure
As a basic sense of intuition we know that the mass of the water that is in the pipe junction at any instant of time is conserved as the junction does not accumulate any mass.
The above statement can be mathematically written as
this is known as equation of conservation of mass / Equation of continuity.
Now we know that in a time 't' the volume that enter's the Junction 'O' is
1) From pipe 1 =
1) From pipe 2 =
Mass leaving the junction 'O' in the same time equals
From pipe 3 =
From the basic relation of density, volume and mass we have
Using the above relations in our basic equation of continuity we obtain
Thus the mass flow rate equation becomes
