Darcy's Fables IV

Estimated Reading Time: 3 minutes 49 seconds. Read Later

A couple of nights ago I was reading to my grand-kids from their favorite book, Piping System Fundamentals. We were reading the section on how to properly specify equipment for a pumped system. They all appeared to be a little confused, so the oldest asked “Pop Pop, why is it so important to know the system requirements when specifying equipment?” I then decided it was time for a Darcy’s Fable.

The Farmers and their Horses' Power

Once in the deep woods there was a bear, a puma, and a wolf. They were all friendly animals wanting to shed their common stereotypes passed down throughout the ages in popular fables and folk stories. These three friends decided to make a career change and tried their hand in farming.

After a couple of days of being farmers they were sitting down together and shared their experiences. They all complained about how hard it was to prepare the ground for planting.

All of a sudden the bear said “I think I will go into town and buy a horse!”

“That’s a great idea,” said the puma, “I am hungry and a horse would taste good now.”

“No, no, no! I want the horse to pull my plow not to eat it,” replied the bear. So, after a lengthy discussion, each of the friends resolved to go to the market and purchase a horse.

The bear told the horse trader, “I am the strongest animal in the forest; I need to buy a big strong horse to plow my field. As I expand my farm to meet my future goals, having a big horse will allow me to pull my big plow and get much more done.” Later that afternoon, the bear came back from the market with a Belgian Draft horse.

The puma told the horse trader, “I am the fastest animal in the forest; I must have the fast horse to pull my plow.  As my farm gets bigger, and to meet my future goals, I would like to have fast horse that will be able to run while pulling the plow.” By the afternoon, the puma came back from the market with a Thoroughbred horse. 

At the horse market the wolf said, “I am not the strongest or fastest animal in the forest, so I must buy smart. What type of horse would you suggest that I purchase to help me around my small farm?” So, later that afternoon, the wolf returned from the market with a mule*.

The bear and the puma laughed at how funny and small the wolf’s mule looked, and teased the wolf for is choice. “That animal will not get the job done at all!” they said to him. The wolf took no mind.

After a week the bear, puma, and wolf were again at their favorite watering hole for happy hour and the conversation turned to their horses.

The bear said that his Belgian horse was so strong it could pull the dark out of midnight. But that it was so big that it wouldn’t fit into the barn.

The puma said that his Thoroughbred could run faster than the wind but it was so high strung that it kicked out the walls in the barn.

The wolf said that his mule was a hard worker, and he enjoyed living in the dry barn.

After the crops were in the bear, puma, and the wolf meet up at the harvest ball. Soon the discussion turned to their farming success.

The bear said that he had to sell his larger Belgian Draft horse. He said that although his crops were in early because his big horse made such short work of the plowing, the horse was so big and hungry it ate half his crops! In addition, the Belgian was just too big to work around the bear’s small farm.

The puma said that he too had to sell his Thoroughbred. His crops were planted late because the horse didn’t want to pull the plow. Due to the late planting and short growing season his crops didn’t come in that well. The Thoroughbred horse enjoyed running but would not help around the puma’s small farm.

The wolf said that with the help of his hard working mule he got the crops planted on time. Since the mule was the right size for the small farm he didn’t eat a lot of the crops and was able to help around the farm. The wolf said that after the crops came in he had enough money to pay all his bills, put some money in the bank for the future, and buy some more land and a second mule to expand the farm.

. . .

All of a sudden one of my grand-kids said, “Now I get it Pop Pop, if you don’t size the process equipment to meet the systems requirements, the operating and maintenance cost will be excessive which affects the plants profitability.”

With a twinkle in my eye I said “Yes my little ones, you learn well.”

The youngest of the grand-kids wanted to know what became of the Belgian and the Thoroughbred horses. Well, the Belgian was sold to a brewery in St. Louis and is making nightly beer runs. The Thoroughbred was sold to a jockey to run at the track but it turns out the Thoroughbred was a nag and never finished in the money and is now working at a glue factory.

* To be correct a mule is not a horse. A mule is the offspring of a male donkey and a female horse. Mules are typically more patient, sure footed, and live longer than a horse, and are typically less obstinate, faster, and more intelligent that donkeys.[1]

If you like reading about my Piping System Fundamentals, Darcy’s Fables, let me know! I’d welcome your version of a Darcy’s Fable as well. Send your email to blogger@eng-software.com. Thanks for reading!

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1.    Jackson, Louise A. The Mule Men: A History of Stock Packing in the Sierra Nevada, p. 5 (Mountain Press Publishing Co, Missoula, Montana, 2004).

Darcy's Fables III

Estimated Reading Time: 3 minutes 38 seconds. Read Later

The other night I was babysitting my grand-kids and they asked me to read them a story from their favorite book Piping System Fundamentals. So I asked my middle grandchild, what part of the book she would like me to read. She said the part about balancing the energy usage within a pumped system and the need to identify and eliminate excess pump head. When I started reading, she said “No Pop-Pop not with those words, make it into a story with kings, and animals.” Well I knew I needed to bring out my old French friend Henry Darcy to create another “Darcy’s Fable.”

 

The Story of the Elephant King and the Busy Beavers

 

Once upon a time, there lived an Elephant King, who liked to provide his subjects with all the best the kingdom could offer. The King decided that for the kingdom to grow and prosper he would need to bring water from Lake Lilly, the giant water hole in the center of the kingdom, to all the cities and villages.

The first order of business was to get the Zebras together to plan the water system for the future and make sure it wasn’t too small. The Zebras came up with their estimate and then doubled it just to be on the safe side. They forwarded their estimate to the Wart Hogs to come up with a design. (My grandson thinks Wart Hogs are nice and wants them in every story!) The Wart Hogs did all their calculations, and since they were planning for the future they too added an ample margin for future growth.

As the system was built, everyone was excited. The Squirrels, having a knack for saving, were in charge of kingdom finances. Since the Squirrels had to pay for the project out of the royal treasury, they were starting to get concerned about the project costs. The project went ahead and was finished on time but over budget. 

The water pumps were big and they took large teams of Horses to run them, but they were bright and shiny. Everyone was impressed with what had been built. Once the water system was finished and the pumps started, there was plenty of water everywhere around the kingdom. In fact, there was too much water in many locations and some of the villages had problems dealing with the water. 

In one farming village, there were floods in the fields but the resourceful farmers planted rice in the fields instead of wheat to try and “fix” or “cover” up the overabundance. In other villages, the excess water went into the streets making it difficult to travel, but it was quickly diverted by the Hippopotami to existing streams that lead back to Lake Lilly. Over time, all the startup problems were solved and the system worked. As the wise Elephant King envisioned the kingdom prospered.

After a couple of months, the Squirrels approached the Elephant King and said that the water project cost twice as much to operate than originally planned. But since the kingdoms productivity increased there was enough in the royal treasury to pay for the increased operating cost.

In the summer months, when the water was needed the most there were parts of the kingdom that didn’t have enough water. The King decided that something needed to be done so he brought in the Busy Beavers to look at the system to see what could be done.

The first thing the Beavers discovered was that some areas in the kingdom got too much water while other areas more distant from Lake Lilly didn’t get enough. The Beavers busily set about to plug some of the pipe outlets in the areas that had too much water. As they started plugging the pipelines close to Lake Lilly, they started getting more water to the more remote locations of the kingdom. As they worked their way out from Lake Lilly, they found that all the pipelines needed to be partially plugged to prevent flooding. Soon the Beavers found that over time, the plugs they placed in the pipelines to balance the flow would spring leaks requiring continual repairs.

After talking to the Squirrels about the operating costs, the Beavers discovered the cost to operate the large Horse driven pumps continued to climb. It seemed the raceway the Horses ran on to drive the pumps was also beginning to wear out. When the dirt raceway was replaced with a stone raceway, the Horses’ shoes wore out much faster and their hooves were splitting, increasing the system maintenance cost. Neither of those solutions worked!

Then the Beavers put two and two together and determined that the pump was too large for the needs of the system. After reviewing the pump curve and performing a few pump affinity speed calculations, they determined that if they replaced the fast Horses with smaller and slower Goats the pump would develop less pressure and would stop blowing out the plugs. After replacing the Horses with Goats, they rebalanced the system and all was well in the royal water system. The Beavers were able to reduce the cost to run the pumps as well as practically eliminate all of the breakdowns and maintenance troubles.

The Elephant King was so happy that the system worked that he had a royal dinner for the Beavers and everyone lived happily ever after.

THE END

My granddaughter was so happy about the story she said “See Pop-Pop, if you optimize a pump, you can reduce your capital costs, operating cost, and maintenance costs while increasing system reliability. I really like stories with happy endings.”

Darcy's Fables II

Estimated Reading Time: 3 minutes 31 seconds. Read Later

I was reading to my grandchildren from Piping System Fundamentals, their favorite book, and enjoying some family time. We were talking about the pump curve, one of the most important documents dealing with pumped systems. They all had questions about reading the pump curve and understanding why it was so important to know where it is running on the curve. Since they had so many questions, I created this Darcy’s Fable to explain:

The Raccoon, Possum, Porcupine, and the Golden Map

Once upon a time was a Raccoon, Possum, and Porcupine lived in the Primeval Woods. Life was hard for the woodland critters, and the past winter was especially long and cold which put everyone in a foul mood. Moreover, food was in short supply and everyone was worried about the future.

As the Raccoon, Possum and Porcupine were sitting by the side of a brook complaining about how hard life was, a beautiful Water Sprite flew by on shimmering wings.

She said to the trio, “I have been listing to your worries and complaints so I thought I would help you out. I will give each one of you a Golden Map. With it, you can find your way to Westwood. There you will find the weather is mild, the food is plentiful and life is much better. Just follow the Golden Map and all will be well.”

Then the Water Sprite flitted off laughing, knowing that her gift would cause misfortune for some of the critters. You see, this sprite was quite mischievous, often tricking people. She then vanished as quickly as she had appeared.

Possum quickly looked at the Golden Map and said, “This looks very simple, I will put it in my backpack and start the journey right away!” However, as the Possum was putting the Golden Map into his backpack, a sudden breeze caught the paper and it fell into the brook where it was swept away.

Possum was undeterred and he said, “No matter, it looked so simple I can easily remember it and find my way to the Westwood,” and he promptly set off.

Then Porcupine looked at the Golden Map and said, “This map must be very important, so I will make sure it is safely in my backpack and I will only take it out if I really need it.” Then he too, immediately set off for Westwood.

After the other two had so quickly gone on their merry way, Raccoon looked at the Golden Map and said, “This must be important, and since Westwood is so very far away I think I will study and learn about this map before starting my journey.”

He then set out to find the Great Owl, the wisest animal in the forest. The Great Owl looked at the Golden Map and after a while, was able to unlock its secrets.

He shared the secrets of the map with Raccoon and showed him the blue line to follow from the Primeval Woods through the Spot of Sweetness and finally going Between the Emerald Peaks (Let’s call it BEP) then your journey to Westwood will be easy.

The Raccoon then set about getting ready and packing for the journey, starting off the following morning. Within two days journey, he made it to Westwood where the winters are mild, the mood bright, and the food is plentiful. Racoon was so thankful he had learned how to read his Golden Map!

But the poor Possum without the aid of the Golden Map went into the “Lowlands of Poor Operation” where there was turbulence, cavitation, and excessive noise. The Possum was so scared in this land that he got totally missed the truck coming down the road he was standing on. Unfortunately he was run over and can still be found by the side of the road.*

*(I always like it when a character dies in a story. It keeps them from being too sappy.)

Porcupine started his journey, but when he looked at the Golden Map, he could not unlock its secrets. He wandered about aimlessly in the “Land of the Rough Running.” The rocks and the thorny bushes cut his shoes and ripped at his cloths and the noise and thunder keeps him awake at night. He was constantly buying new shoes and wandering around with tattered clothing, a very miserable porcupine. 

Suddenly one of my granddaughters exclaimed “Now it get it Pop Pop, for every pump in the plant we should have a pump curve. We should know where each pump is running on its curve and try to operate Between the Emerald Peaks, I mean around the BEP. If we do that we can reduce both its operating cost and maintenance cost.”

Her sister, always the romantic said, “Pop Pop whatever happened to the Raccoon in Westwood?”

I said that he is currently in a long-term relationship with a very attractive girl raccoon and they are looking to have a litter of kits when the time is right. She seemed satisfied with that answer so I chose to leave it at that!

If you'd like to learn more about reading pump curves. Engineered Software Knowledge Base has a couple articles that might help.

Reading a Pump Curve and Pump Curve Landmarks are both very informative.

Let me know what you think of these Darcy's Fables. I have at least one more to share, but I'd like to know what you all think about them. (Read The First Darcy's Fable Here) Leave a comment below or send an email to blogger@eng-software dot com. Thanks for reading!

Darcy's Fables

Estimated Reading Time: 3 minutes 33 seconds. Read Later

Here is a picture of me reading to my newest grandchild. All my grandchildren love to be read to, and one of their most favorite books is Piping System Fundamentals, which I co-wrote with Jeff Sines of Engineered Software. They like the ease at which the book explains difficult concepts of piping systems along with the compelling graphics. 

As you can see from the picture he has a question about NPSH. It seemed his older sisters told him that NPSH stands for “Not Pumping So Hot” so he wanted to have me set him straight. I told him to watch out because older sisters like to tease younger brothers.

All my grandchildren enjoy the stories in Piping System Fundamentals, but sometimes the topics are a little difficult to understand. As a result I often change the story by making it into a fable.*  Aesop was the master of fables in western cultures, and I still remember my mother reading them to me growing up. 

So I thought I would create some of my own fables to tell to my grandchildren. I decided to call them Darcy's Fables in honor of Henry Darcy, the Frenchman that help develop the equation for calculating head loss due to friction in a pipeline.   

So here is my first Darcy's fable called:

The Wise Cat in the Tree of Knowledge.

Long ago, there was a village built around a Tree of Knowledge. People would come from all over the land each bringing their unique customs and languages to this wonderful village. The people of this village would all sit under the Tree of Knowledge, work together and come up with ideas for wonderful things that everyone wanted. Each clan had their unique powers, there were the Sparks with their electric personality, the Newtonians, possessing an understanding of all things mechanical, and the Chemists, using their knowledge to make the most amazing things from the most basic of elements.

After many years, each group got so involved with what their clan was doing they developed their own "secret" language that could only be understood by their fellow clan members. Since each clan used their own "secret" language it became difficult to exchange ideas at the Tree of Knowledge. Each clan continued to work to develop the most amazing things, but since each group thought they knew the answer, they stopped listening to each other.

One day a young page boy was walking by the Tree of Knowledge and spied a wise cat sitting on a branch. Our young page climbed up into the tree and started petting the cat. The cat enjoyed the attention and started purring as all cats do.

After a good scratch, the cat said to the youngster, "Because you are so kind and took the time to pet me I, will grant you the power to explain."

The young page said, "I don't understand!"

The Wise Cat rose and started to walk away saying, "In time, you will understand. Come back tomorrow and I shall let you pet me again."

The young page came back to the Tree of Knowledge every day to pet the Wise Cat. Every day he would listen to each clan as they discuss their ideas and talked about their problems at the Tree of Knowledge. (In this magical land, yes, they continue to solve problems, and don't have issues!) While the young page pet the cat he would listen to each clan, and after many days, he started understanding each clans’ "secret" language. The young page discovered that each clan was interested in the same thing, but since they didn't understand each other’s "secret" languages, they were unable to explain themselves or work together. 

Then the young page had an idea, if I can cast everyone's problems into a language that everyone can understand, then all the different clans’ members can work together to solve common problems. The boy grew very excited.

“They just need to speak the same language!” he exclaimed.

Instead of creating a new language, our young page decided it would be best to use ideas that were common to all. He chose to explain the various items in terms they already understood, the local form of money, the “Want.” (Because everyone wants something.)  Everyone was paid for the work they did, the things they needed, and saved for a rainy day using the local currency of the Want. By explaining using money, all the members of each clan could understand the common solution using a customary unit that everyone understood. 

As a result of the young page’s gift, the “power to explain,” the clans could come to the Tree of Knowledge and have a place to present their ideas in a common language all could understand. The village continued to grow and all was prosperous and well.

The moral: If you want others to understand your ideas, use a common language that can be understood by all.

*A fable is a short story featuring animals, mythical creatures, plants, inanimate objects and forces of nature to illustrates a point, lesson, or moral which is often explicitly stated at the end.  (I specifically chose the fable here instead of a parable form of prose, because the parable excludes animals, and all kids love those funny little critters.)

Tell me about your favorite fables or stories from your childhood. Leave a comment below or send an email to blogger@eng-software dot com. Thanks for reading!