Recent content by Jack.C

Thanks for the response. Unfortunately, not. I don't understand why we have to think that complex - or is there no way to simplify it? There is no pump. There is an isolated pipeline filled with water that is being drained with 3 drains (length of pipeline is not relevant, amound of drains is...

We could just assume something. I also randomly generated the profile and the amount and locations of the three drains. Let's assume: Lowpoint / Q1 at KP 02+500 / Elevation = 22 masl Lowpoint / Q2 at KP 05+000 / Elevation = 20 masl Lowpoint / Q3 at KP 07+500 / Elevation = 10 masl Highpoint...

Hi LittleInch Thanks! Let's assume that there is sufficient air intake capacity provided. All we are trying to understand is how the HGL will drop over time when the drains are open. At some point of course the HGL will be at the level of that hump on the right. So there will be water remaining...

We are aware that there must be air vents installed to avoid vacuum in the pipeline during drainge. The question is related to define a simplified approach to evaluate the head drop over time. Let's leave the temperature, altitude effects etc. away as this would not lead to a simplified approach.

Hi Hturkak. The valves at both ends are closed. We are aware that Q3 is highest. But the question here is how to calculate the head drop. Regards, Jack.

Hi, Kindly asking for your help on belows query. Let's assume a 10km long DN1000 pipeline with 3 drains at the low points. The initial head is H1 (orange line). After a time step dt a certain amount of water has left the system (I'm using the Toricelli approach) through the 3 drains. How...

Thanks a lot for your valuable insights and sharing your expertise. @EdStainless: Yes, indeed, we are discussing spikes with peaks lasting only a few seconds. This is why I raised the question regarding the potential impact on the pipes when we briefly exceed the design pressures. I assume that...

Hi all, I'm looking for advice on best engineering practices for simulating a hydraulic pipeline, particularly regarding the maximum allowable pressure for HDPE pipes during transients. I'm currently working with a PE100 PN16 water pipeline (SDR11) and have calculated a Maximum Operating...

Hi LittleInch, Thanks for this explanation! Thoroughly helpful.

Dear all. Thanks a lot for your feedbacks. Really helpful! @Snickster: My drain rates are even higher than this. I have a DN1200 pipe around 30 km in length. The complete line is divided into two sections. The maximum drain time is given by client. Therefore, we added for each section a larger...

Dear All, I am reaching out once again with a question and would greatly appreciate your valuable insights, as you have consistently provided in the past. Kindly refer to the accompanying sketch for context. Situation: I am currently dealing with an isolated pipeline that is being emptied via...

Hi all @LittleInch: Noted. Thanks for your advice! I'll definitely consider that in my proposal. @1503-44: Agree with you. I think it's a matter of experience. Some operators are more convenient by setting the Q setpoint and some with P setpoint. The pipes will be designed accordingly by...

Hi Pierre! Thanks for this reminder. Check valves at discharge side are foreseen for each pump. I don't see the need to have an additional one at the pumping station outlets. Do you agree on that? Best regards, Jack

Dear all, Thanks a lot for your feedback. I really appreciate that. @1503-44: I'm not sure yet if we are expecting a varying flow rate or not (>80% or < 80% of maximum flow for a longer time period) -> will be clarified. However, I've learned that at both stations we have a buffer tank of...

Dear all, I have a situation here which has been bothering me for a while and I really hope someone can give me their expertise on it. Background: I have two pump groups (let's assume three pumps in parallel each), which deliver up to 1.5 m3/s maximum. The amount delivered can vary between...