A liquid of density
The dimensionless relationship for
Answer to Problem 67P
The dimensionless relationship for
Explanation of Solution
Given information:
The number of variable parameters is
Expression for number of pi terms,
Here, number of variable parameters is
Substitute
Expression for first pi terms,
Here, pressure difference is
Expression for second pi terms,
Here, dynamic viscosity is
Expression for third pi terms,
Here, volume flow rate is
Expression for pressure,
Here, force is
Substitute
Expression for dimension diameter,
Expression for density,
Here, mass is
Substitute
Expression for angular velocity,
Substitute
Expression for dynamic viscosity,
Substitute
Expression for dimension of volume flow rate,
Substitute
Expression for relation of
Calculation:
Substitute
Compare the exponent of
Compare the exponent of
Compare the exponent of
Substitute the
Substitute
Compare the exponent of
Compare the exponent of
Compare the exponent of
Substitute the
Substitute
Compare the exponent of
Compare the exponent of
Compare the exponent of
Substitute the
Substitute
Conclusion:
The dimensionless relationship for
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