## Surface Area of a helical coil?

## Surface Area of a helical coil?

(OP)

I need the formula for calcuating the surface area of a helical coil. I have the pipe diameter, coil height, # of turns, and pitch, but can not seem to remember the formula used. Any help would be appreciated.

Thanks.

Thanks.

## RE: Surface Area of a helical coil?

Maui

## RE: Surface Area of a helical coil?

## RE: Surface Area of a helical coil?

N*PI*D*sqrt( 1+ (P/(PI*D))^2 )

where:

P=pitch

N=# turns

D=diameter of helix (the helix in the center of the pipe)

Multiply the helix length by PI*d

d=pipe diameter (either ID or OD, whichever you're looking for)

SA=N*PI^2*D*d*sqrt(1+(P/PI*D))^2)

Pesy

## RE: Surface Area of a helical coil?

_{1}=[(2*pi*r)^{2}+p^{2}]^{0.5}Total coil length,

_{t}=N*L_{1}where N is number of turns, pi =3.1416, r is the coil radius, and p is the pitch.

The external surface:

_{t}*pi*d_{o}Where d

_{o}is the coil's pipe external diameter.## RE: Surface Area of a helical coil?

Any error in this assumption would be no greater than the errors in your physical property data and the heat transfer correlations.

Where ever possible - KISS!

regards

Harvey (Katmar)