Subscribe: Engineering Expert Witness Blog
http://feeds.feedburner.com/EngineeringExpertWitnessBlog
Preview: Engineering Expert Witness Blog

Engineering Expert Witness Blog



Published by Philip J. O'Keefe, PE, MLE



Last Build Date: Mon, 16 Apr 2018 13:41:24 +0000

 



One way to Reduce Cavitation by Increasing Water Pressure

Mon, 16 Apr 2018 13:41:24 +0000

If you’ve ever seen a movie featuring divers, you’ll no doubt be aware that the deeper a diver goes, the more water pressure there is bearing down on him from above. The same goes for a centrifugal pump’s storage tank.



Manipulating Water Temperature to Control Cavitation

Mon, 09 Apr 2018 17:36:47 +0000

Today we’ll see how just manipulating water temperature can control cavitation.



The Principle of Continuity – What Goes In Must Come Out

Mon, 02 Apr 2018 13:45:29 +0000

Continuity has to do with the rate of water flowing through pipes, valves, and pumps within a plumbing system.



Cavitation Bubbles Degrade Pump Performance

Sun, 25 Mar 2018 17:51:40 +0000

This decrease in the water’s density causes the pump to be less efficient, because for any given amount of horsepower that’s conveyed to the pump’s impeller by an external power source, the pump’s ability to promote water discharge is compromised due to the bubbles.



Rapidly Imploding Bubbles Create Problems

Mon, 12 Mar 2018 18:42:26 +0000

Today we’ll see how these rapidly imploding water vapor bubbles create serious problems in the pump’s high pressure area.



Centrifugal Pump Impeller Action

Fri, 02 Mar 2018 22:20:09 +0000

Inside a centrifugal pump both low and high pressure areas are created, chiefly due to the action of the pump’s spinning impeller.



A Centrifugal Pump’s Curved Features are Key to Functionality

Wed, 21 Feb 2018 18:17:33 +0000

Even a casual glance at a centrifugal pump will disclose its many curved features. As the illustration shows, both the housing and internal impeller blades, are curved.



Centrifugal Pumps Can Create Vacuums

Thu, 08 Feb 2018 14:39:29 +0000

Just as in our experiment, if pressure is lowered to 0.23 PSI, water present at the pump inlet will boil at 59ºF, causing thousands of tiny steam bubbles to form and the pump to cavitate.



How Decreasing Pressure Contributes to Cavitation

Sun, 28 Jan 2018 21:17:34 +0000

Cavitation can occur without a heat source. In our pot example, we can start the cavitation process by simply decreasing the pressure of the air resting on top of the water, thereby also decreasing the water’s pressure.



Thermodynamic Properties of Water and Cavitation

Mon, 15 Jan 2018 21:59:58 +0000

To understand how cavitation comes into play, we’ll explore a branch of engineering known as thermodynamics.