Diesel generator fuel supply and return pipes sizing

[romanskat]

Hi mates,

Appreciate if anyone can teach me how to size the supply and return line of an diesel generator from its diesel tank.

Thanks.

 

[TheBlacksmith]

Most manufacturers and thier sales staff will have charts of recommended sizes. It is in thier best interest to ensure a correct installation that will allow the engine to perform as advertised. With the specific lack of info in your original post, this is the best advise available.

 

[BigInch]

Or at least specify a minimum inlet pressure and flow.

http://virtualpipeline.spaces.msn.com

 

[Artisi]

and the distance from the tank to the engine

 

[budt]

Do you know how much fuel per hour the engine burns?

If so, use charts for line flow for diesel fuel (Gasoline, Water) GPM or GPH and size the lines for a low pressure drop for the distance it has to flow.


Bud Trinkel, Fluid Power Consultant
HYDRA-PNEU CONSULTING

 

[romanskat]

Thanks budt, anywhere i can get the chart ?
So, correct me if i understand you wrongly ;we should size the supply line based on the fuel consumption per hour. Then what about for return line?

I attach the fuel schematic that we looking into.The fuel tank is about 50metre away , with plinth (height to be determined). trying to understand the basic theory and correct way of sizing.

Thanks for the guidance.

 

[budt]

The schematic was no help, it was very faint when I opened it and looked like nothing I have ever seen that was called a schematic.

I just did a Google search for "Diesel fuel flow pressure drop and found this site:

http://www.engineeringtoolbox.com/william-hazens-equation-d_645.html

There were a bunch of others also.

I like

http://www.google.com,

it saves me a lot of time waiting for answers.



Bud Trinkel, Fluid Power Consultant
HYDRA-PNEU CONSULTING

 

[BigInch]

Here,

http://www.preferredutilities.com/

http://virtualpipeline.spaces.msn.com

 

[budt]

That's even a better one BigInch. I only hope I can Favorite it to some place I can find when I need it.


Bud Trinkel, Fluid Power Consultant
HYDRA-PNEU CONSULTING

 

[RossABQ]

Return line size is usually close to full-size for one diesel's consumption, since there is one fuel pump on prior to start of first diesel, and two on when one is running and 2nd is going to start, etc.

 

[Artisi]

There are many variables that we are not advised of at the moment, height of the storage tank in relation to the engines, length of the main line from the tank to the the split to individual lines, flow rate required (fuel consumption at full load of each engine), what pressure is required at the engine injection pump/s.
You can get the fuel consumptionn from the engine performance curve or from the manufacturer. If we have this information we can then give you some advice that will assist you.

 

[Artisi]

following up on my earlier post, if you know the maximum power output of the engines when the gensets are at full load you can calculate the fuel comsumption(at full load).

A diesel engine will use somewhere between 0.4 and 0.5 lb/hp/hr of fuel- when operating at full load at a set speed.

You can therefore approximate the fuel required for your gensets accuratley enough to size the pipe requirments.

As an example: an engine running at 100hp output the consumption becomes;

100 x .5 = 50 lbs
assume 7.5 lbs per US gallon = 6.7 gallons/hr

Trust this helps - but we still need more detail to size the pipework.

 

[MJCronin]

roman,

As I understand your sketch,

- There is only a "gravity feed" from the bulk diesel tank to the genset

- You do not show any pumps or "daytank" commonly found on gensets (a daytank is commonly required for fire protection requirements)

- What provides the pressure for the fuel return line back to the bulk tank ? Perhaps a pump that you do not show ?

-MJC