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I just got back from the
2010 Valve World Conference and Exhibition in Dusseldorf Germany. It was a long trip through 10 time zones. Engineered Software had a booth at the exhibition and I had the privilege of giving two presentations at the conference. The conference was three days in length and then it was back on the plane for a long ride home. The conference was well attended despite the snow storm and record cold for all three days of the conference.
My wife and I really enjoyed the city wide Christmas celebration with hundreds of street vendors selling German food, gifts, candy, and mulled wine. The first evening we arrived we were outside in the snow, on a crisp and clear night enjoying a hot cup of mulled wine with 400 others. After two cups we made it back to the room and fell fast asleep without any problems with jet lag.
After setting up the booth on Monday and a good night’s rest we were ready to go. The show traffic was great and we met some of our existing customers along with meeting many new engineers involved with the design and operation of piping systems from around the world.
One of my discussions with a visitor was particularly noteworthy. On the second day of the conference, an entourage of four came to the booth, a man in his late 50’s lead the group followed by three younger men in their 20’s (Photo 1). The older gentleman only spoke Russian and German and one of the younger men translated. We introduced ourselves through the younger translator and found out the older man was Professor Gancho Dimitrov from the
University of Architecture, Civil Engineering and Geodesy in Sofia Bulgaria. Since I had taught two Engineered Software classes at the Worley Parsons office in Sofia two year, earlier we had something in common and the conversation progressed.
 |
This is me talking to Professor Gancho Dimitrov (far right)
and his
students at the Valve World Exhibition. Special thanks
to our translator,
the young gentleman between us two old guys. |
Professor Dimitrov had many years of operational experience and had written multiple text books on water and waste water treatment. He then asked if I could set up a simple system using the software with multiple pumps. I created a system using metric units
(I am "MSU" engineer, Metric as a Second Unit). He wanted a system with three pumps installed and with a total system flow rate of 600 m3/hr. I then selected a pump to pass 200 m3/hr with the total head needed to pass the system flow rate of 900 m3/hr. When I placed the three pumps in the system, the calculated total flow rate was 600 m3/hr, with each pump passing 200 m3/hr. He then wanted me to turn off one of the pumps and calculate the flow through the system with two pumps running.
I knew what he was up to; he wanted to check to see that the flow rate through the two pumps operating in parallel was something less than 400 m3/hr. A typical rookie mistake is in thinking that running two pumps in parallel will translate into two-thirds the flow rate of three pumps in parallel. That subject is covered in detail in our Piping System Fundamentals class. As soon as he saw the answer on the PIPE-FLO screen he immediately started drawing a multiple pump curves on a system curve and talking to his student doing the translation. See figure 1.
Figure 1.
This is the system Professor Dimitrov’s sketched showing how multiple pumps in a system should operate when the resistance is a mixture of both static head and dynamic head caused by pipeline head loss. Notice that with the mixed system when only one pump is running the pump passes 320 m3/hr, two pumps running passes 500 m3/hr, and when all three pumps are running, passes 600 m3/hr.
I knew I needed to look into the system to find out the reason for this unlikely event. It turns out that the system that I designed in PIPE-FLO was dominated by static head, with very little dynamic head loss due to pipe friction (Remember metric units are my second units). The result was a very flat system resistance curve, almost horizontal. While he was still drawing his system curve (Figure 1), I started drawing my system curve (Figure 2) showing how multiple pump curves intersected a resistance curve dominated by static head. As you can see from the system curve, each of the three pumps under this unusual situation produces 200 m3/hr each regardless of the number of pumps running.
Figure 2.
This is the system that I had created in PIPE-FLO to show how the system operated. I had not realized that the system that I create was a system dominated with static head. Notice how the flow rate through each pump is 200 m3/hr.
As soon as each of us had our turn explaining our systems with the unfortunate student translator, we both agreed that the PIPE-FLO program produced accurate results for this highly unusual system example.
You could say that a system resistance curve was considered a universal language used to describe the operation of operating piping systems. I had a great time talking to Professor Dimitrov and promised to visit the next time I’m in Sofia Bulgaria.
If you have an opportunity to visit a trade fair in Europe, I would suggest you go, even if you have to work it around a vacation. Valve World was rather small only 20,000 attendees, but was for a very specifically targeted audience. We will also be exhibiting at another international trade show, ACHEMA 2012, running from June 18th – 22nd. The 2009 show drew over 179,000 attendees, and had over 23,000 exhibitors! Like I said the Germans really know how to have a trade fair.
Now it’s time to hear from you. What trade shows do you plan on visiting and why? What value do you find in attending trade shows? What predictions do you have for the 2011 trade show season?
Please feel free to share your experiences, or opinions on this blog entry or any other subject that is of interest. Leave a comment below or
email me. I can be reached at blogger@eng-software.com.
