Home
Back
Formula Used:
| From: | To: |
The Coefficient of Discharge (Cd) is the ratio of actual discharge to theoretical discharge through an orifice. It accounts for energy losses and flow contractions that occur in real fluid flow situations.
The calculator uses the formula:
Where:
Explanation: The coefficient of discharge is the product of the coefficient of contraction and coefficient of velocity, representing the combined effects of flow contraction and velocity reduction.
Details: The coefficient of discharge is crucial for accurate flow rate calculations in various engineering applications, including pipe flow, orifice meters, and fluid system design. It helps account for real-world deviations from ideal flow conditions.
Tips: Enter the coefficient of contraction and coefficient of velocity as dimensionless values. Both values must be greater than zero and typically range between 0.6 and 1.0 for most practical applications.
Q1: What is the typical range for coefficient of discharge?
A: For sharp-edged orifices, Cd typically ranges from 0.6 to 0.65. For well-designed nozzles, it can approach 0.95-0.99.
Q2: How does orifice shape affect the coefficient of discharge?
A: Different orifice shapes (circular, rectangular, etc.) and edge conditions (sharp, rounded) significantly affect both contraction and velocity coefficients, thus affecting the overall discharge coefficient.
Q3: What factors influence the coefficient of contraction?
A: The coefficient of contraction depends on orifice geometry, edge sharpness, and the Reynolds number of the flow.
Q4: How is coefficient of velocity determined experimentally?
A: Coefficient of velocity can be determined by measuring the actual jet trajectory and comparing it with the theoretical trajectory under ideal conditions.
Q5: Why is the coefficient of discharge less than 1?
A: The coefficient is less than 1 due to energy losses (friction, turbulence) and flow contraction at the vena contracta, which reduce the actual discharge below the theoretical ideal.