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mparsons06
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Flow Rate Problem - Please Help!
1. Homework Statement :
SAE no. 10 oil has a viscosity of 0.2 Pa· s. How long (in sec) would it take to pour 6 liters of oil through a funnel with a neck 12 cm long and 2.6 cm in diameter. Assume that it is poured in such a way that the oil level is kept just above the top of the tube.
Hint: The specific gravity (= ratio of its density to that of water) of the oil is 0.70.
The pressure difference is given by
Dp = rgL
1000 liter = 1 m^3 = 10^6 cm^3
The flow rate is given by Poiseuille's law:
Q = p * r^4 * Dp / 8*h*L
You can calculate the pressure difference:
Dp = rgL
Dp = (700 kg/m^3)(9.81 m/s^2)(0.0012 m)
Dp = 82.4 Pa
And the time it takes for the oil to flow through is the volume of the oil divided by the flow rate:
t = V / Q = 8 * V * h * L / (p * r^4 * Dp)
t = 8 (0.006 m^3)*(0.2)*(0.012 m) / p * (0.5)*(0.013 m)^4 * (82.4 Pa)
t = 8.97 X 10^-9
But I know that can't be right. Can someone please help me with where I went wrong? And try to explain it to me?
1. Homework Statement :
SAE no. 10 oil has a viscosity of 0.2 Pa· s. How long (in sec) would it take to pour 6 liters of oil through a funnel with a neck 12 cm long and 2.6 cm in diameter. Assume that it is poured in such a way that the oil level is kept just above the top of the tube.
Hint: The specific gravity (= ratio of its density to that of water) of the oil is 0.70.
Homework Equations
The pressure difference is given by
Dp = rgL
1000 liter = 1 m^3 = 10^6 cm^3
The flow rate is given by Poiseuille's law:
Q = p * r^4 * Dp / 8*h*L
The Attempt at a Solution
You can calculate the pressure difference:
Dp = rgL
Dp = (700 kg/m^3)(9.81 m/s^2)(0.0012 m)
Dp = 82.4 Pa
And the time it takes for the oil to flow through is the volume of the oil divided by the flow rate:
t = V / Q = 8 * V * h * L / (p * r^4 * Dp)
t = 8 (0.006 m^3)*(0.2)*(0.012 m) / p * (0.5)*(0.013 m)^4 * (82.4 Pa)
t = 8.97 X 10^-9
But I know that can't be right. Can someone please help me with where I went wrong? And try to explain it to me?
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