DIYbanter - View Single Post - Pipe joins and pipe sizing for heating oil

The Natural Philosopher[_2_]

On 13/05/2021 13:10, wrote:
Hmmm, after a bit more thought I'm beginning to realise that this is not
an easy one. Oil is incompressible so *I think* this means that, to a
first approximation, the narrowest bore sets the flow resistance.
No.
flow through pipes is like current through resistors = the longer and
also the narrower they are the more pressure drop for a given flow rate.

You need to add the 'resistances' all together. So short inserts wont
hurt too much.

The equations that approximate behaviour are friction to the walls. The
larger the bore the more cross section area to surface area there is.
Surface area is 2πR times length, cross sectional area is πR²...so
volume per unit wall area varies as R...

--
The New Left are the people they warned you about.