How do you find the Reynolds number for a sphere?
The most widely studied case is the sphere. Figure 1 graphs the dependence of drag coefficient for a sphere and a cylinder in crossflow on the Reynolds Number Re = ρuD/η, where D is the sphere (cylinder) diameter, η the viscosity of liquid, and .
How Reynolds number is related with coefficient of discharge?
Also, in the equation for discharge coefficient, Reynolds number is in the denominator, which means if viscosity is higher, Reynolds number is lower, and the coefficient of discharge is also higher, which results in higher flowrate for the same pressure difference in front of and after the orifice.
What is the Reynolds number for a sphere in laminar flow?
So, when the Reynolds number is below 2,300, we can expect the flow to be laminar, and when it is above approximately 4,000, the flow will be turbulent. In between these two limits, the flow is termed “transition flow.” Page 2 2 We can ascribe a certain physical significance to the Reynolds number.
What is the formula for calculating Reynolds number?
Reynolds number formula (equation) The Reynolds Number formula is: “Re = VDρ/μ” or “Re = VD/v” where “V” is the fluid velocity, “D” is the characteristic distance, “ρ” is the fluid density, “ν” is the kinematic viscosity, and “μ” is the dynamic viscosity both of which can be acquired from data tables.
How is orifice flow coefficient calculated?
To estimate the orifice flow rate:
- Insert the diameter of the orifice, d = 50 mm .
- The calculator will now estimate the area of orifice, A .
- Enter the coefficient of discharge, Cd = 0.8 .
- Enter the value of the mean center line, H = 200 mm .
- The acceleration due to gravity, g is filled in as 9.81 m/s2 .
Is discharge coefficient a function of Reynolds number?
The discharge coefficient is the actual flow ratio with the theoretical flow and makes allowances for flow contractions and friction effects. The discharge coefficient is a function of the Reynolds number while the Reynolds number is a function of the flow rate calculated using the discharge coefficient value.
Does the discharge coefficient increase with Reynolds number?
It has been also found that the orifice discharge coefficient reduces with increasing in Reynolds number for all values of beta ratio especially at the turbulent flow regime and hence adequate must be taken while designing such orifice.
What Reynolds number is turbulent sphere?
Laminar–turbulent transition For flow in a pipe of diameter D, experimental observations show that for “fully developed” flow, laminar flow occurs when ReD < 2300 and turbulent flow occurs when ReD > 2900.
