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@@Niranjankumar-hc5vp do you mean laminar flow?

I think we are making the same point. If we have enough renewables to turn off all gas fired plants, then we need to store the excess renewable power. If we don't have a surplus of renewable power (which is the case in Alberta, Canada) then it is the wrong time to use battery storage. Renewable generating capacity must come first. Storage must come second.

I promise not quit my day job. Thanks.

Good question. If the system curve is flat then the motor requires constant torque and variable speed. The amount of heat generated by the motor is proportional with motor speed. But a fan cooled motor may lot be able to provide enough cooling at reduced speed. I have not calculated the amount of cooling at lower speed. I suggest only using VFD where there is steep system curve and no danger of overheating.

Thank you.

Data is available at https colon // kevindorma dot ca/2021/03/17/using-data-science-to-quantify-ciwh-and-the-suppression-effect-of-air/

I stand corrected. Thank you. They have excellent guidelines for process engineering.

Three pistons.

We use the same approach as electric circuit with resistors in parallel. There is a current balance at each branch. Each resistor uses V=I R. With electric circuit we get a matrix equation for all V and I. With hydraulics the equations are quadratic.

A VFD should (almost always) consume less power than fixed speed pump and control valve. This is because the control valve must take 10-20% of the total pressure drop. I did not clarify where the inlet is. This is the pipe inlet (pump discharge). I assume pump suction P constant. System curve is the pipe, starting at the fixed outlet pressure. Pump curve is the pump discharge, which is the pump DP plus suction pressure.

@@kevindormaconsulting4763 I think there's also a case for using a control valve if the situation calls for a process to be isolated from the pump, and using a valve is necessary for that. Where there are multiple destinations, it's possible only one of the control valves would be eliminated with the use of a VFD. You still may save some energy with a VFD though.

The nameplate will be the rpm that the motor will run at rated voltage and frequency. The higher the frequency at the top end, the lower the torque. Depending on the application, this can be an issue in itself. There will be diminishing returns here and if you need to run faster than 60hz, then you're most likely going to need a different motor than the one you're intending to use. VFD's can not be put on just any motor as well. I'm sure you can find most of this information to answer your questions with a quick google search.

I have asked that question a few times. The answer I was given is You might be able to go a little faster than synchronous, but not a lot faster. Higher speed draws more power and may damage the motor. I don’t know if a VFD can be applied to any motor. Good question.

This methodology is based on Darcy Weisbach. The difference is the friction factor is correlated with a different set of parameters. The standard correlation for friction factor produces a nonlinear equation in diameter. Frictional pressure drop is roughly proportional to D^5. You could use an iterative method to solve this equation.

Yes. I assume you mean a real pipeline. Something that is several km long and you want a specified pressure drop.

I was assuming that we need a design margin 30% on flow.

I have not created them yet. Sorry.

@@kevindormaconsulting4763 Please make whenever you are free.

Perry’s chemical engineers handbook, sixth edition, page 5-25, equation 5-65.

thankyou very much sir. Your method of teaching is really helpful and awesome. If you have free time then please make more videos on pipe flow and piping stress analysis if possible. Also it is request to you to recommend some TH-cam channel or suggest book covering practical pipe flow and stress analysis problems or at least share your valuable data with us.

Thanks. We usually learn through failure, but we tend to share successes.

Thank you. I don’t have a lot of time right now. I will do that when I have time.

@@kevindormaconsulting4763hello sir, is this lesson applicable for calculating the discharge line of a tank?

@@khenkhen08 Yes, but this pipe may be short. It this case you need to check the pressure drop from the entrance loss. You should also check if the drain line could produce a vortex and pull gas into the line.

@@kevindormaconsulting4763 Hello, Sir. In calculating the pipe size diameter of tank’s discharge, do i need to consider the mechanical energy balance of that tank to the tank where it will be transferred or i can just isolate and make a mechanical energy balance around the tank that I will design?

The Benifits with emissions depends on ambient temperature. It is pretty chilly at Caroline (I did a bit of work at the plant to the south). That said, the CO2 intensity of Alberta power has gone down since then. But the cost of a CCASHP is a killer.

CHP makes sense for places that are cold and do not have a surplus of renewable power (hydroelectric). Here we use gas turbines as the best way to supply electricity. CHP recovers more energy from natural gas than a gas turbine. CHP may be a poor solution for places with abundant hydroelectric power.

Start with a drawing of the piping system. Show the main header for each floor, and the branch lines for each consumer. Then you need to decide the amount of DP that can be taken for the main header and the branch lines. This is always the list difficult part. What is the basis for the flow rate through the main header and each branch line? How much design margin do you want for these flow rates? These are difficult questions but very important. If the main supply is at 500 kpa then decide the pressure you can accept at each consumer. It may be 450 kpa. You can take 50 kpa for the entire path. How much DP will you permit for the main header, and how much for the small branch to consumers? You might decide 20 kpa for main header and 30 for branch. What is the piping length for main header and for the longest branch? This gives you the DP per 100 m. How much design margin do you need for each line?

Thanks. I have plans for shaft drive with 15 lb flywheel and two flexible couplings. Poor man’s dual mass flywheel.

Line sizing is performed long before we know what the pipe route looks like. It is simply a way to choose a reasonable flow velocity. Perhaps engineers should look at this and consider the number of bends in the path and the overall pressure we can afford to lose. This might be a nice topic for a Masters Degree research project. Thanks for asking.

@@kevindormaconsulting4763 well I just asked because in duct sizing we consider the the fittings first before we size.

@@arielmcdowny2367 ahhhhhhh. An elbow has an equivalent length of about 30 duct diameter. Ducts are usually short but there may be several bends. 6 bends in a 24 inch duct is equal to 360 ft of duct. The duct may be only 50 ft long. Thanks for the knowledge.

It is my pleasure.

That is a good question. I have never seen a derivation of the affinity laws. I need some time to think about this.

Thank you so much for your reply! Together with this question, I try to give an answer to another similar question: The pump creates/increases pressure or flow?

Consider 4000 kpa steam that is used to heat the feed stream, and suppose we do not want the feed temperature to exceed 200 c. The steam could heat this to 260 c. In this example I made the temperature stable by placing the steam control valve in MANUAL at 50% open. But this is not under control. I need to find the cause of oscillation and fix it.

@@kevindormaconsulting4763 @Kevin Dorma Consulting yes, agreed. Manual control has its own very limitations, and requires high estimation skills from the manual operator. Which again is scarcely limiting. For this reason we use automated PID controller. I believe that the cause of oscillation is due to disturbances in the upstream, could be due to increased flow rate, increased pressure. I believe that a finely tuned pneumatic valve would work the best here, to maintain the temperature under range.

Each constraint is a value that we must not exceed. Pick the larger diameter. One example where a larger pipe is bad is slurry flow. Low velocity causes deposition. The simple rules do not apply here.

@@kevindormaconsulting4763 For single phase fluid flow, the larger pipe should be used, considering pressure drop. That means pressure drop has more weightage than Velocity. Yes, i agree with the slurry flow. I remember in the Biogas Project, the pipe diameter was reduced from 20" to 16" from FEED to Detailed Engineering, when hydraulics were verified.