What is friction factor in fluid mechanics?
Definition of friction factor The friction factor is representing the loss of pressure of a fluid in a pipe due to the interactions in between the fluid and the pipe. f/2=friction factor – fanning. D=Pipe diameter in m. um=mean velocity in m/s.
How do you calculate the friction factor?
How to calculate friction factor for turbulent flow?
- Calculate the Reynold’s number for the flow (using ρ × V × D / μ).
- Check the relative roughness (k/D) to be under 0.01.
- Use the Reynold’s number, roughness in the Moody formula – f = 0.0055 × ( 1 + (2×104 × k/D + 106/Re)1/3)
What is Darcy friction factor in fluid mechanics?
The Darcy friction factor is a dimensionless quantity used in the Darcy-Weisbach equation for the description of friction losses in pipe flow as well as open channel flow. It is also known as the Darcy-Weisbach friction factor or Moody friction factor and is four times larger than the Fanning friction factor.
What is the significance of friction factor?
In turbulent flow regime, the friction factor plays a very important role as the pumping power is related to the friction factor. The friction factor formula given by Colebrook – white equation (C-W equation) is a [1] combination of Prandtl and Von karman and also it is mostly preferred because of its accuracy.
What are 5 examples of fluid friction?
Fluid Friction
- Air pushing against your hand when you stick it out the window of a car (external)
- Water pushing against a swimmer’s body as they move through it (external)
- The movement of your coffee as you stir it with a spoon (external)
- Sucking water through a straw (internal)
- Submarine moving through water (external)
What is the friction factor of steel pipe?
0.003-0.03
Friction Factor
| Pipe Material | ɛ ft |
|---|---|
| Riveted steel | 0.003-0.03 |
| Concrete | 0.001-0.01 |
| Wood stave | 0.0006-0.003 |
| Cast iron | 0.00085 |
What is the friction factor of water?
From the Moody diagram, for R = 59,516 and (e/D) = 0.000129, we get the friction factor as f = 0.0206. Using the Moody diagram, determine the friction factor for a water pipeline with a 400 mm outside diameter and a 6 mm wall thickness at a flow rate of 400 m3/h. Viscosity of water is 1.0 cSt.
What is soil friction factor?
4.3.1.4 Soil Friction Factor. Friction factor (μ) is defined as the ratio between the force required to move a section of pipe and the vertical contact force applied by the pipe on the seabed. This simplified model (Coulomb) is used to assess stability.
How do you find the friction factor of a smooth pipe?
When the Reynolds number is greater than 4,000, turbulent flow regime, the smooth pipe friction factor can be calculated using a Blasius type equation as (4.38)f = 0.184(N Re) − 0.2 At large Reynolds numbers, the friction factor is independent of fluid viscosity and only depends on the roughness of the pipe.
What is the friction factor of coolant?
where ρ is the coolant density and u its velocity (the dynamic pressure 1/2ρ u2 is the rise in pressure that ideally could be obtained if the coolant were slowed down to zero velocity). An alternative friction factor sometimes used is the Darcy—Weisbach friction factor defined by
How does the friction factor depend on the Reynolds number?
The friction factor depends not only on the Reynolds number but also on the relative roughness. ( ɛ / d ) , that is, Roughness of pipe walls ( ɛ ) compared to diameter of the pipe. The friction factor for smooth pipes (e.g., brass tubing) decreases more rapidly with the increasing Reynolds number than for the pipe with comparatively rough walls.