Simple Physical Testing

Objective

Obtain a better understanding of the operation of your water treatment device.

Equipment / Supplies

Your water treatment device, water treatment device manual, ruler, calipers, balance, stop watch, beakers.

Method

  1. Read the water treatment device manual, figure out how the water treatment device works (e.g., what path does the water take, are their check valves?, how is the water treated,...),
  2. Measure and draw it's parts by hand, start creating AutoCAD or Solid Works drawings (see drawing handout). Measure the stroke length or squeeze length, if appropriate.
  3. Identify manufacturer' claims/patents,
  4. Identify specifications (e.g., manufacturer's claimed treatment device cartridge capacity, flow rate, size of particles filtered, microbe removal percents, water treatment device "level" (e.g., 1 or 2, is it a purifier or not...),
  5. Check out the manufacturer web site,
  6. Identify the cost of the water treatment device and its components,
  7. Measure the amount of water that can be treated in one minute at a number of different stroke rates (strokes/min). Try to pump at a constant rate. Do this for 6 to 9 different stroke rates, spanning from a low stroke rate that achieves about 10% of the manufacturer's claimed flowrate to as high as you can go. Measure the number of strokes (or squeezes) and volume of water (Liters) treated in a minute. Water bottles may not be able to go a full minute. Calculate the stroke rate, stroke velocity (velocity of piston in cm/sec), and flowrate (liters/min) for each test. Plot stroke rate (strokes/min) on the x-axis versus flowrate (liters/min) on the y-axis. Based in this experience, what do you think is an easily obtained flowrate? What is the maximum flowrate attainable? Is the relationship between stroke rate and flowrate linear? Over the entire range of stroke rates tested? When comparing the results of different treatment devices, does it matter if your water treatment device pumps on the down and up stroke or just the down stroke? Do up and down strokes take the same time? If not, measure the difference.

...and anything else you can think of! This information should be recorded in your laboratory notebook, with sources clearly identified.

Putting your water treatment device away

Read the manual to see how to store your water treatment device before the lab is over.

If your data are unacceptable, you will be expected to repeat experiments outside of normal class time.