What about if I control the feed system only with the pressure loop?
The PD pumps have ramp-up time, I can let supply pumps to ramp faster and start on slightly higher pressure set point. Also I suppose that the pressure tank will help to maintain enough water when the fog system switches on...
That is the thing, there are two information
fog system supplier requires 1,5*rated flow = 12 m3/hr or 6 m3/hr at 3-4 bars
PD pump manufacturer 2*rated flow = 16 or 8 m3/hr at 1-2 bar
I asked the supplier why this mismatch and he told me that during the designing the system they hired...
Hi all!:) I think I have it! If I put istead of 2nd pump 2 similar but smaller pumps in parallel, I will be able to operate even close to BEP in both cases wheter fogging is operating at 4 m3/hr or 8 m3/hr and also I reduce cycling because there will be main and auxillary pump. I will create...
At first I would like to thank you all for having an interest in my problem and especially to Snickster for so extensively looking through it.
Exactly. This is right. There is an additional 30-45 meters of head in the curve representing the need for a pressure. If you subtract this, you will...
1. yes
2. head in m
3. first pump submerged in the tank for Ebara Matrix alternative
4. also first pump in series with Ebara 3M alternative
The pressure will be created by restricted flow by the fogging system, which will always limit the flow to either 4 or 8 m3/hr depending on whether both...
Interesting and very important point! I have to look at that as well.
Other than that, in terms of performance and behaviour, do you see any pros and cons of either system?
Hi. this is a follow up on my previous post. I think it would be better to make a new thread because there is a clear, specific question now.
My project is about supplying water to our fogging system which is basically another pump and also end user flow.
The requirements from the device's...
Yes but due to friction loss and static head, it will deliver no more than 12 m3/h as seen in the system curve.
Do you think for my operation it's better to choose less steep pump? I would say that yes, because it will give more steady control by VFD over the flow and head to supply the fogging...
Hello, I calculate minor losses in fittings using coefficient of resistance and data provided by the dealer.
If I have mechanical fitting such as this 90 deg elbow
The total minor loss is only 1x elbow (coef 1.2) or 1x elbow (1.2) + 2x connection (0.3 for d75)?
Do I have to count the...
yes they are centrifugal pumps. The system should feed another technology which needs 8-10 m3/h flow and 4 bar pressure at its inlet.
First pump PSP 18-22
Second pump Ebara Matrix 10-5
This is the system curve from the first pump to the suction of the second. The Q will be 12 m3/h, which is...
Hello, I have a general question regarding 2 different pumps in series.
In this situation the head is added and flow remains the same Q = Q pump1 = Q pump2.
Also I read if the capacities of the pumps are different the flow is determided by the smallest pump.
But in practical situation , what...
