How to Calculate Pressure Drop Through a Coiled Pipe?

It depends on the flow, the viscosity of the fluid etc.

With no flow there is no pressure drop.

• Diameter and length of the pipe?
• Its internal roughness?
• Elevation difference between inlet and outlet?
• What's in the pipe?
• Temperature?
• Pressure?
• Density?
• Viscosity?
• Flowrate?

Answers to that lot would form the basis for a start to be made!

Also add diam, type and class of pipe and radius and spacing of coil.

Is the pipe deformed in any way while coiling?

Sorry for the confusion, this was not a question as basic as "how to calculate pressure drop" this question was asked assuming the basic knowledge of pressure drop calculation is well known, and that all physical data is known i.e. density viscosity roughness factor Reynolds number etc. and that the user is familiar with using this data for pd calcs in straight pipes, bends, valves, tees etc

Now for the real question, "is there a known formula that can be used when the pipe is not straight but it is coiled. "

There have been quite a few papers written on the subject but most are only concerned when the flow is laminar. In practice most flow through coiled pipes is turbulent, not laminar. Hence the question is for a practical method for this pd calc.

regards

d

Unless the coil is there to counteract the Coriolis Effect, as a fist assumption, the equivalent length of the pipe when straightened out would be good enough for a first approximation.

Apologies for the confusion. The original posting gave no hint that the required data and the basis for the calculation technique were already to hand.....

You can use empirical DP(coil)=DP(straight)*(1+3.54*d/D), where d-internal diameter of pipe; D-diameter of coil by axis of pipe.

Regards,

Boris

egorenko@era-cross.com

I have a 1965 copyright "Flow of FLuids" Crane Technical Paper No 410 that has a couple of pages on the subject and provides bend coefficient factors based on radius of pipe. See if you can get a copy of pages 2-12 thru 2-13 and A-27.

The pressure drop difference across a coiled pipe verses a straight pipe is insignificant as they both have turbulent flow. The molecules at the center of the pipe are at maximum velocity while the molecules at the wall are at zero, depending on the pipe's surface tension and the physical properties of the shies you're trying to put through it. Are you sizing a pump or exercising engineers? The angle of the dangle is inversely proportional to the fling of the ding.

RT Pokin

For all practicle purposes, the same as for an equivalent length of straight pipe