Pump It! Design-Build-Test Helpful Village Water Pumps
In 1993 the Mississippi and Missouri rivers flooded many Midwest cities, causing $15 billion dollars in damage. In this photo, pumps are used to save downtown Alton, MO, by pumping water over a wall of sandbags.Copyright NOAA National Weather Service http://water.weather.gov/ahps2/images/hydrograph_photos/alni2/93flood_alton2.jpg
Pumps are used to get drinking water to our houses every day! And in disaster situations, pumps are essential to keep flood water out. In this hands-on activity, student groups design, build, test and improve devices to pump water as if they were engineers helping a rural village meet their drinking water supply. Students keep track of their materials costs, and calculate power and cost efficiencies of the prototype pumps. They also learn about different types of pumps, how they work and useful applications.
We often take for granted the dependable supply of clean drinking water and dry homes, thanks to the hard work of civil engineering and pumps. Pumps play a major part in supplying us with drinking water and they also play a large role in mitigating floods, especially when natural disasters strike. Civil engineers must have a detailed understanding about how pumps work in order to choose the right pump for the job in drinking water plants and disaster relief. In the U.S., most pumps that supply drinking water are operated by large electrical motors, while in less-developed countries and extremely remote areas, many hardworking pumps are simple hand-operated devices.
Meredith, a University of Colorado student, designed a simple displacement pump using PVC piping. The pump uses one-way valves that she built with washers and springs, and a plunger made from a threaded rod with a rubber washer at the end. As Meredith pulls the plunger up, water enters the lower one-way valve and fills the chamber made of larger PVC. Then when she pushes down the plunger, the lower one-way valve closes and water exits through the nozzle.Copyright 2012 Mike Soltys, College of Engineering, University of Colorado Boulder
After this activity, students should be able to:
- Explain how a centrifugal pump works and how a displacement pump works.
- Calculate the power output of a pump.
- Convert lb-ft/s into watts and horsepower.