[esp-r] FW: Modelling a Machinery Room

[Matthew Wright]

This maybe over simple, but hopefully it helps.

Regards
 
Matt
Matthew Wright MA Physics (Oxon) PGCE
Physicist
 
e: Matthew.Wright at c4ci.eu
m: +44 (0)7908030742
p: +44 (0)1823 277316
 
 



-----Original Message-----
From: Matthew Wright [mailto:matthew.wright at c4ci.eu] 
Sent: 30 July 2009 09:05
To: 'Felipe Durán'
Subject: RE: [esp-r] Modelling a Machinery Room

Felipe,

Try this analysis as a first approximation, it should be fairly good.

The gains to the plant room will effectively be the losses from the
generators.

That is there will be power input, mechanically from the turbines, and a
power output from the turbines.
The difference between the two at any time will be the power left in the
plant room.
This energy flow will come in several forms; heat, sound, mechanical wear to
components, etc.
It is a fairly safe assumption that the vast majority of this dissipated
energy will become heat in the room.

This gives -

(heating power into room) = (power into turbines) - (electrical power out)

Most generation equipment should have efficiency graphs, tables, and
coefficients. That is, you can relate (usually through a fairly constant
number) the amount of power out to the amount of power in. If you know the
amount of power being produced over time (the rated power here is 2 x 6000
kW) you can relate the (power in) to the (power out).



(Mechanical power in) x efficiency = (Electrical power out)

Note:  efficiency will be less than 1.00, a fraction or decimal


This rearranges to give -

power out (12000 kW)/ efficiency of turbines = mechanical power into plant
room.

This should allow you to find the difference and the residual heat.


Hopefully this is not too simple an analysis and helps.

You could try working from the energy of the water falling through the
turbines, but you would have to know the efficiency of the mechanical
turbine, and calculations with the torque and rotational speed are possible
for the generator input, but you shouldn't need that level of detail.

*For a more realistic analysis, try getting the actual electrical power
output records, and relate them to the power input as suggested. It is rare
for any plant room to run at full capacity all the time.*

Regards
 
Matt
 


-----Original Message-----
From: esp-r-bounces at lists.strath.ac.uk
[mailto:esp-r-bounces at lists.strath.ac.uk] On Behalf Of Felipe Durán
Sent: 29 July 2009 22:11
To: esp-r at lists.strath.ac.uk
Subject: [esp-r] Modelling a Machinery Room

Dear All:

I am modelling a machine room of an hydroelectric plant which has two 6000
kW generators.

It would be an enormous help if anyone could tell me about the internal
gains of that room. Any suggestions about how to figure out how big the
internal gains produced by the generators would be ?. Any suggestions about
how to model that kind of internal gains?

Thank you in advance.

Felipe Durán Palma
Arquitecto PUC, MPhil. U. Cambridge
Director de Proyectos y Asesorías