On the Energy Front

Since the first of the year I have traveled 43,000 airline miles, taught three Piping System Fundamentals courses, attended a major trade show and visited countless customers.  It seems that everyone is asking what can be done to reduce their energy consumption.  I really enjoy that questions because of my deep involvement in helping people find the answers to that question.

I am a member of the ISO 14414-TC115-WG07 Pumping system energy assessment committee. I spent two days with 12 other committee member in Phoenix, AZ  to work on the final draft prior to submission for a wide review. We had members present from Europe, South America, and the United States, along with extensive comments from other members around the world.  The standard presents a variety of ways to look at how piping systems use the energy. 

In addition to the ISO meeting I’m a member of the Hydraulic Institute / Pump Systems Matter (HI/PSM) committee revising their Pump System Optimization course.  This course focuses on the value of conducting pump system assessments, and how to set up and conduct an assessment program.  

Since the first of the year, I have written a monthly column for Pumps & Systems Magazine on Pump System Improvements. Links to the articles can be found below:

•  Jan 2014 Solution for Pump Discharge Pipe Cracking
•  Feb 2014 Finally Justifying Improvements
•  March 2014 A Financial Justification for Pump System Improvement
•  April 2014 Overcome Resistance to Program Upgrade

They are a great group to work with and I would like to send out a special Thank You to Amanda Perry. She is a fantastic editor and does a great job of turning my submissions into a clear and concise article. I'm excited to share that last month they told me my column has been picked up for the remainder of 2014! I would encourage you all to get a subscription to Pumps & Systems Magazine, it’s full of excellent articles, and industry news. 

Once again, if you have any questions or comments please feel free to leave a comment. 

PIPE-FLO Nuclear

Millstone Power Station. Image via www.nrc.gov

Now that PIPE-FLO Nuclear is nearing its release, one of our new employees asked me how someone in a nuclear power plant could use the new program. That got me thinking about my first job after getting out of the Navy. In 1975, I was hired by Northeast Utilities as a start-up and test engineer at Millstone Unit 2 in Waterford Connecticut. I was assigned to a group of five engineers involved in a pre-operation test in which we balanced the component cooling water system. The component cooling water system is a safety related system and must be operational after a postulated accident.  
This involved test went on 24 hours a day for about two weeks. It started when the engineers at Bechtel in Gaithersburg, Maryland (the EPC for the plant) sent us a datasheet with the prescribed valve position as the initial “guess” for balancing the system. 

During the second shift, the plant operators placed the component cooling water system in the proper configuration for the test. The team of test engineers would place the throttle valves to the prescribed valve position. Once this was done, we would then record the pressures and flow rates using the installed plant instrumentation. We would compile the information into a report; type in onto a report and by about 5:00 AM, would finally fax the results to Bechtel in Gaithersburg.
 
During the day, a group of engineers at Bechtel evaluated our test data from the night before, and after a day of calculations, compiled a new set of valve positions. They would then type a report with the new valve positions and fax it to us by 7:00 PM, so we could repeat the process. This was an iterative process and after each round of test data and new valve positions, the flow rates to each load in the cooling water system got closer to the design values. This process continued for about two week until the results were within the prescribed value outlined in our Final Safety Analysis Report (FSAR for short).

Image from the 1999 movie "Office Space", where
disgruntled workers obliterated their fax machine.

As you can see this was a team effort with about ten engineers in two location working around the clock to balance a critical system in a nuclear power plant. Even the FAX machine required two full time operators, using a Xerox Magnafax Telecopier, one at Millstone the other in Gaithersburg. Let me quickly describe this arduous process and this is such old technology I could not find a picture of one anywhere on the internet, but try to imagine with me. The fax machine was a hefty 46 pounds and was connected to a standard telephone buy inserting the phones handset into an acoustic coupler. The operator sending the fax would place a call on a POT (Plain Old Telephone) to the operator on the receiving end. The sending operator would then place the page on a drum, to start the process the drum would rotate, the machine would screech and once the two machines were talking to each other the receiving operator would flip a switch and the Fax would come through line by line. After six minutes, a single page was done and the operators would then manually reload the paper on each end and start the process for the next page in the report. With two good operators, we could transmit a six-page report in an hour! 

As you can see, technology has come a long way. About 10 year ago, I met up with one of the test engineers from Millstone. He was now in plant management and said that they used PIPE-FLO to calculate the valve positions needed to balance his plants cooling water system. I asked him how long it took with PIPE-FLO, and he said once the model was validated, the valve positions were calculated within seconds. The operators then set the valves to the prescribed position and then took the pressure and flow readings just like before. Now they would compare the calculated values with the observed values. If the results were within the prescribed values, the test is signed off. He said from start to finish they were able to balance their equipment cooling water system in less than a day. 

In 2005, the NRC granted Millstone 2 and 3 a 20-year extension on their operating license after an extensive 22-month review process. I find it remarkable that after 40 years, the plant that I helped start up is still running and has another 10 years of operation. 

One of the reasons that the US civilian nuclear power program has been so successful and safe is because of the quality requirements placed on the equipment, and the training requirements of the plant personnel.


Our soon to be released PIPE-FLO Nuclear program comes with an extensive Commercial Grade Dedication in which we document the engineering methods used, outline our development and testing programs, along with an extensive set of test procedures that we developed. To automate the testing process we use PIPE-FLO’s DataLink feature to export design data and calculated results from the PIPE-FLO model to any ODBC capable program like Microsoft ® Excel® or Access®. 

Using the Excel spreadsheets included in the PIPE-FLO Nuclear, one is able to compare PIPE-FLO’s calculated results with the results calculated using Excel. The Excel Verification Worksheets utilize conditional formatting to automatically highlight any values greater than those specified in the Acceptance Criteria. By using Excel, anyone can review the formulas use in the spreadsheets and validate our check calculations.

Nuclear power plants have used PIPE-FLO for over 20 years, but until the release of PIPE-FLO Nuclear, each of our utility customers had to develop their own Commercial Grade Dedication, which may take months to develop. Since a Commercial Grade Dedication needs to be performed for each new version of PIPE-FLO, and the cost is so high for them to perform the work, many use older versions of PIPE-FLO. 

By making PIPE-FLO Nuclear available to our nuclear customers, they will benefit from the latest versions of the software much more quickly. They will still need to run their own commercial grade dedication, but using our supplied templates, they will be able to do their own CGD in a fraction of the time.

Now that is progress. 

It Flies Just Like the Simulator

Estimated Reading Time: 3 minutes 37 seconds. Read Later

The Pacific Northwest is home to The Boeing Company and as such, the first flight of any new aircraft is big news.

When the 787 Dreamliner made its first flight, the two test pilots stated, “The airplane flies beautifully, it did exactly as we expected. No surprises and no major issues with the airplane.” 

Prior to conducting the first actual flight, the test pilots “learned to fly the aircraft” using a flight simulator and will do this before any inaugural flight. These simulators have all the flight characteristics of the 787 Dreamliner in the program, which is how the test pilots knew what to expect on the first flight. Flight simulators range from multi-million dollar three axis flight simulator to flight simulator programs for use on PC’s.

Boeing 787 Dreamliner Flight Simulator - image
courtesy The Boeing Company boeing.com

One of the things I like best about my job is the ability to visit customers to see how they are using PIPE-FLO. The majority of our customers use PIPE-FLO to perform the preliminary design of their piping systems, specifically to obtain the design data needed for equipment selection. More recently though, I’ve been learning that more of our customers are entering increasingly detailed design data for their completed systems into their PIPE-FLO models. This provides them a better understanding of how the finished design will operate once it is placed in service. 

For example, one of our long time PIPE-FLO customers needed to add cooling loads to a large cooling water system in their chemical process plant in Houston, Texas. The system was previously modeled using PIPE-FLO to determine if a new pump was needed for the proposed expansion. Once the system was modeled in PIPE-FLO, they determined that the existing pumps could meet the projected needs.

As the design became finalized, the PIPE-FLO model was updated with the design changes of the expanded cooling water system. After conducting a simulation, they were able to determine the valve positions of all the throttle valves. This was accomplished by entering the Cv characteristics of each throttle valve in the system into their PIPE-FLO model. Once this was done, PIPE-FLO calculated the valve position and identified that cavitation would occur in two of the control valves. Once the problem was identified in the simulation, the valve supplier was called in to see what could be done to correct the problem. The valve supplier suggested changing out the cavitating control valves with a different design. The model was updated with the new valve characteristics and the problem was solved. All this was done well before commissioning the expanded system.

When it came time to start up the expanded cooling water system, all the control valves were set to their calculated balanced valve position and the system was brought online. The client stated that normally it took an outside contractor two to three days to balance the cooling water system by manually adjusting things after taking readings. Using the valve positions calculated in the PIPE-FLO simulation, it only took half a day to validate that the system was balanced. Additionally, it was confirmed that no cavitation occurs in any of the control valves.

Many of our customers said it was difficult to get valve operating data for their control valves, so in PIPE-FLO 12 we made it easier by creating the Control Valve Estimator. Using default data found in the ISA 75.01.01 and IEC 60532 Industrial Process Control Valves standards, you are able to answer a few questions about control valve construction as well as the fully open Cv, and the program will create an accurate representation of control valve operation.

One of PIPE-FLO’s unique features is the used of manufacturers’ electronic pump catalogs. Using the same electronic pump catalogs the manufacturers use to pick a pump for customers, you are able to insert the pump into the piping system model to gain an accurate simulation. Once again the PIPE-FLO uses the methodology outlined in a variety of Hydraulic Institute standards for pump operation.

Finally, flow elements such as orifices, nozzles and venturi types are accurately modeled based on the applicable ASME and ISA standards. 

During the simulation, all the information is factored into the total calculations. For example if during the simulation the user changes the temperature of the process fluid the program:

• Looks up the fluid properties of density, viscosity, and vapor pressure and use this information in all calculations. 
• Calculates the head loss in all the pipelines affecting the pressures throughout the system.
• The change if the fluids vapor pressure and head loss in the suction pipeline affect the NPSH available at the pump suction.
• The vapor pressure also affects the cavitation calculations for control valves, flow meters, and pressure calculations throughout the system.

As you can see any change in the operating piping system affects the operation of every item in the system. 

I would be hard pressed to say that a PIPE-FLO simulation has as much entertainment value as a flight simulator program, knowing how much I love flying aircraft, but it can show you a clear picture of how your piping system operates. And that type of solid reassurance and validation is exactly what you need before you take a multi-million dollar system online for the first time. Leaving you to say on your inaugural start-up, “The system runs beautifully, it did exactly as we expected. No surprises and no major issues with this piping system!”

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Testing 1, 2, 3...

Estimated Reading Time: 5 minutes 26 seconds. Read Later

The Importance of Product Testing

As mentioned in my September blog, Engineered Software will be celebrating 30 years in business in 2012. In that post I listed the core value we have followed to better meet our customer’s needs and expectations, specifically:

1. Create a sustainable company
2. Create product that can be used by a wide variety of people, not just engineers
3. Play well with others.

In this month’s blog I will be sharing with you how our software testing has evolved over the years.

When we started Engineered Software both Carolyn Popp and I (the two founding principles) saw the value of developing a testing program for our software. Our feeling was, if we released a program that had a calculation error, our customers might not trust our new company. In addition, if the customer had trouble entering the necessary data or lost data due to a problem with the program, we were not providing them with the value they expected. For the first version of PIPE-FLO, we developed a series of program features; the formulas the calculations were based on, along with a set of example calculations. These example calculations included a variety of edge cases designed to test the program source code.

I developed a series of test problems from text books, technical publications such as the Crane Technical Paper 410, along with developing a series of calculations performed using an electronic calculator (remember 1982 pre-dated Lotus 123 and Microsoft’s Multi-Plan). A set of calculations sheets were developed complete with the equations, references, all input values, along with intermediate and final calculated results. Prior to every program release, these examples were entered manually into PIPE-FLO and the results validated. Carolyn, a former IBM system engineer, was just as adamant on program testing and validating prior to program release.

Our third & fourth employees, Jaclyn and Kathleen Byron (we often called them J&K), both with mechanical and civil engineering degrees, were hired to improve our program testing, provide customer technical support, and assist in software development. Based on their customer interaction they were able to created test procedures to validate all engineering calculations along with the user interface. They also were responsible for automating the test procedures by developing test scripts for each program feature.

When one of the software developers finished a new PIPE-FLO feature, J&K created an automated test, and checked the results. Any problems with the new feature were brought to the attention of the programmer and resolved. Once we had a PIPE-FLO release candidate, we would perform all automated tests again to validate the software results prior to release. The release testing took approximately 2 – 4 weeks to complete, allowing the correction of last minute program bugs, along with a review of the test results.

As our company grew, we added more programmers and engineers to our development team. In 2006 we decided it was time to update our software development and testing practices by implementing the Agile Software development process.

The major impact was to document the proposed program features and so everyone knows how the feature works. The process starts by engineers creating “stories” for each feature describing how customers used the feature. The application developers would write the program code to meet the requirements listed in the “story”, and the developers in test would develop the testing needed to ensure PIPE-FLO meets the “story” requirements.

Testing is now broken down into unit stages:

• Unit Testing
• Integration Testing

To demonstrate I’ll use an example for calculating the fluid Reynolds number. First engineering first creates a “story” defining the Reynolds number calculation, the data that must be supplied, and a variety of examples with the calculated results.

The application developers create a function for calculating the Reynolds number. The new function is placed in the function library used by all developers that need to calculate the fluid Reynolds number. In addition the developer creates a “unit test” based on the example calculations supplied by engineering in the “story.” The unit test is then placed in the unit test library that is run every time the program is compiled by any developer.

Now let’s say the developer creating the orifice sizing feature needs to calculate the fluid Reynolds number of the orifice. The software developer will use the previously defined Reynolds number function. If the function needs to be modified for the orifice sizing calculations, (say using the orifice diameter instead of the pipe diameter) then the Reynolds number function in the library may be modified by the developer writing the orifice feature. Once a developer compiles the program on their local computer the Reynolds number unit test will be performed to insure nothing was changed that would give bad Reynolds number results for either the pipeline or orifice Reynolds number calculation. If the test fails the developer knows immediately there is a problem in the Reynolds number function and makes the necessary correction.

Once the developer has completed the orifice sizing feature on their computer they check in their code to a central build server. The build server is where all programs are compiled for release. Once the code is checked in on the build server all unit tests are performed on the code, if any problems occur the developer is notified immediately. The build server performs all unit tests each time any one of the application programmers check in their source code.

Integrated Tests are developed by a separate group of programmers that specialize in software testing. The developers in test create the integrated tests to ensure the program’s higher level features work as called out in the “story.” The majority of these tests are developed to test PIPE-FLO’s user interface.

For example in PIPE-FLO the pipeline graph window shows the fluid Reynolds number over a range of flow rates. The developers in test will create an integrated test to check that the graph window is acting as defined in the story. For example the integrated test may check to see that the Reynolds numbers are graphed and displayed and the user also has the ability to change the color.

In the past the integrated testing was conducted when the feature was initially added to the program, and at the completion of the program prior to program release. The time difference between initially adding the feature releasing the program could be measured in months. During that time span a developer may make a change in a new feature that has an effect on a previously tested feature.

With our new automated testing once an integrated test is written to test a feature it is added to the test suite on the testing server. Every night the test server performs all automated tests.

In the evening, the test server takes that day’s program from the build server and loads it to the test server. The test server loads the current program onto multiple computers on the test farm. The test server then assigns the various integrated test to each computer and keeps track of the results. Currently there are about 10 computers in our testing farm and it takes approximately 6 hours to perform the test and review the results.

The next morning each member of the development team can check to see if the code they wrote yesterday has an adverse effect of the program development. If any of the tests fail the developer will be notified and can make the necessary changes that day.

This testing has paid off for both Engineered Software and our customers. In the last two versions of PIPE-FLO we have only had to issue one maintenance release to correct problems associated with the program. A more reliable program means less stress for such important engineering choices, and our aim is to make our customer’s job easier.

I would love it if you left a comment or even sent me an email to blogger @ eng-software.com. Also, we are currently welcoming guest bloggers. If you are interested, just send me a message about becoming a guest blogger, and what you would like to write about. Thanks for reading!

It’s the System Not the Pump: DOE’s Proposal for New Pump Efficiency Standards

Estimated Reading Time: 4 minutes 40 seconds. Read Later

This post covers the US Department of Energy (DOE) notice of proposed rule-making for pump efficiency. On June 13, 2011, the US DOE issued a Request For Information (RFI) regarding the establishment of energy conservation standards for pumps. (http://www.gpo.gov/fdsys/pkg/FR-2011-06-13/html/2011-14553.htm). After viewing the information found on the Federal Register RFI, I have serious doubts about some of the estimates presented along with the value of establishing minimum pump efficiency standard.

The RFI states there are other regulatory programs that provide energy efficiency information such as the Energy Star labeling program developed by the US Environmental Protection Agency and DOE. The Energy Star labeling can be found for a variety of products such as refrigerators, dishwashers and dryers.

The Energy Star labeling program deals with appliances that are typically standalone devices. For example, your refrigerator doesn’t work with any of the other appliances in your house, making it very easy to determine how much power it will take to operate a standalone appliance in a year.

A pump on the other hand, is part of a total system that may be called on to operate in a variety of ways during a year, with a variety of flow rates through the pump. As a result, a program similar to an Energy Start labeling program for pumps would have limited value.

The RFI continues that pumps are not covered under the Energy Star labeling. It further states in “The US DOE has the intention to evaluate the energy savings potential of energy conservation standards, labels, or both, for commercial and industrial pumps.” They continue with “After public comment on this RFI, DOE will consider developing test procedures and energy conservation standards or labels for this equipment.” (Bold & italic entered by the author.)

One area in the RFI that I have real concerns about is their estimation on the availability of pump efficiency improvements. It states:

“Reports cited in this RFI estimate potential energy savings from pumps of 10 percent to 50 percent. Because these estimates include a variety of system and pump efficiency measures including proper sizing of equipment, the lowest energy savings estimate of 10 percent, based on an European Union (EU) study of pump efficiencies (cited in (c) below), is assumed for the pump efficiency alone.”

The reports cited in the statement estimating a potential energy savings from pumps of 10 percent to 50 percent are based on finding of a variety of Pumped System assessments. The energy savings are based on system related issues. A pump does not know or care how the energy it supplies to the system is used, it only reacts to the system’s needs.

For example if a pump operating with a 100 psi discharge pressure, delivering a flow rate of 300 gallons per minute and has an 80% pump efficiency, that pump consumes a given amount of energy. If the system requires 300 gallons per minute at only 60 psi a control valve could be installed to reduce the pressure by 40 psi to what is required by the system. The pump still remains 80% efficient but approximately 60% of the supplied energy by the pump to the system is wasted across the control valve. Remember, the purpose of the control valve is to reduce the excess pressure provide by the pump to that needed by the attached system.

In this example there could be a 40% saving in energy consumption by running the pump at a lower pressure and eliminating the control valve. To accomplish this, an adjustment must be made to the pump so it only produces the 60 psi required by the system. This can be accomplished by either changing the pump impeller diameter or by changing the pump rotational speed. These types of decisions are made when performing an assessment of the total pumped system.

What I really disagree with is the statement “… the lowest energy savings estimate of 10 percent, based on European Union (EU) study of pump efficiencies is assumed for the pump efficiency alone.” What they seem to be saying is based on their experience they could expect at least a 10% system efficiency improvement by improving the pump design. Earlier in the RFI it is stated:

"Pump system efficiencies depend on design factors such as surface roughness, internal clearances, solids handling capability, curve shape, mechanical shaft seal losses, and other factors.

Analyses based on data from the 2003 EU ”European Guide to Pump Efficiency for Single Stage Centrifugal Pumps ”show that for typical flow rates it is reasonable to expect an efficiency improvement of 10 percent from the mean pump efficiency to the maximum practically attainable level."

The European Guide to Pump Efficiency for Single Stage Centrifugal Pumps referenced in the RFI statement above appears to provide an indication to the pump buyer if the pump being supplied by the manufacturer is the most efficient pump. The main focus of the article is to select a pump where the system requirements are close to the pumps Best Efficiency Point based upon the pump design. I was unable to see how a pump’s efficiency could be improved by improving surface roughness, internal clearances, curve shape or mechanical seal losses.

In 2009, I attended the Hydraulic Institute (the North American pump manufacturers association) annual meeting in Marco Island, FL. During that meeting I sat in on a session presented by EuroPump (the European pump manufacturers association) describing a recent statute passed by the EU to increase pump efficiency for industrial centrifugal pumps.

What was really interesting, is the EU enacted the statute without any comments or discussion with the pump manufacturers. I find it amazing that a group of bureaucrats can state that pump efficiency can be increased by 10% simply by changing internal clearances, increase the smoothness of the castings and changing the shape of the pump curve. If it was that simple it would already have been done!

Rather than looking at new ways to develop test procedures and energy conservation standards or labels for pumps the US DOE should concentrate their efforts on their Superior Energy Performance^cm program. The Superior Energy Performance program is based on the recent Energy Assessment for Pumped Systems ASME E-2 2009 standard which concentrates on the evaluation of the entire system rather than concentrating on just the pump.

Pump manufacturers, as well as owners and operators of pumps and pumped systems, have done an excellent job of developing a variety of test standard and ways of presenting the data. The various standards have been developed by the ASME, HI, ANSI, and ASHRAE over the years to meet the needs of both the manufacturers and buyers of pumps. The standards are also reviewed on a periodic basis to ensure they are current and reflect the latest technology. Anyone who has been involved in the development or review of a standard will attest to the care to ensure the standard meets the needs of everyone concerned.

I would love it if you left a comment or even sent me an email to blogger @ eng-software.com. Also, we are currently welcoming guest bloggers. If you are interested, just send me a message about becoming a guest blogger, and what you would like to write about. Thanks!