I see how introduction of VFD's complicates things, but what if throwing them out is not an option. Let's say that like in the example above I have two 100hp VFD pumps and then one 250hp constant speed pump.
The way I understand this, the best way to run would be the following:
1)...
Hi all,
I am currently working on a project that requires evaluation of overall pump system efficiency, specifically in cases of waste water treatment facilities. My goal is to determine what pump combination is more efficient for a given incoming flow rate in order to maintain the same level...
Thanks to everybody for their help. I ended up creating one big table of temperature and pressure (for superheated region), with values of enthalpy as independent variable. The way I was planning on doing it in my post from 14 june 14:28.
Afterwards, with some rearranging I was able to input...
@ racookpe1978
1) The normal industrial boiler range ... whatever that is. My boss wants to be able to sell this to whoever has a mid to large size boiler, mostly in waste treatment industry. [fuel type: natural gas, oil and sewer gas]
2) This is just "monitoring program" as of right now. The...
Thanks everybody for your help. I think I will try both methods and see what I get.
@ PaoloMPemi
Table is alot of work, however, my boss said he has access to some data analysis software that should be able to pull out two-variable equation:
h=A*pressure + B*temperature (that's an example...
@PaoloPemi
it's worth a shot. I'll try to come up with one big table listing superheated enthalpies for different pressures for given tempatures, like this:
P
T 200 psia 275psia 300 psia .....
------------------------------------------
200 h...
Is there another way to find enthalpy of superheated steam besides the steam table?
Using
h_super=h_sat + Cp*(T_super-T_sat)
would have been really nice and straighforward, but it is no use if I can't figure out the Cp.
Like I said in eariler post, the whole point of this is to be able...
That's what I did in the very beginning. Evaluating shomate equation at T=650K, I got:
Cp=36.9017 kJ/(kmol*K) = 2.053 kJ/(kg*K) = 0.490 Btu/(lb*F)
That is a legit value, however it applies for T=T_sat. The value for Cp at T_super=650K, should be around 0.675 Btu/(lb*F). That is where I got stuck.
I've been working on this for a few hours and I still can't figure it out. Here is what I got using shomate equation for Cp over the range of added superheat from T_sat=526K (488F) to T_super=650K (710F) with 4 degree intervals for the total goal of superheat used of 124K. In order to get my...
I can see that being an issue, so if I just use T_superheated in shomate's equation, it given me Cp value for that temperature but as if the temperature I used is T_sat. Then how do I actually find Cp for superheated steam, knowing it is superheated steam and the temperature? Is their a...
Hell all,
The company I recently started working for, asked me to design boiler efficiency program that can monitor efficiency in real time using instantenious (almost) inputs from several flow meters as well as temperature and pressure transducers. The efficiency equation itself is not...
