Search results
Results from the WOW.Com Content Network
The conventional pump testing method is a method which relies on flow measurements rather than temperature measurements to obtain the performance curves of pumps. Hence, the thermodynamic method differs from the conventional pump testing method largely in what is measured, and how those values are calculated. [6]
Pump curves are quite useful in the pump selection, testing, operation and maintenance. Pump performance curve is a graph of differential head against the operating flow rate. They specify performance and efficiency characteristics. Performance tests are done on the pumps to verify the claims made by the pump maker.
If an NPSH A is say 10 bar then the pump you are using will deliver exactly 10 bar more over the entire operational curve of a pump than its listed operational curve. Example: A pump with a max. pressure head of 8 bar (80 metres) will actually run at 18 bar if the NPSH A is 10 bar. i.e.: 8 bar (pump curve) plus 10 bar NPSH A = 18 bar.
The affinity laws (also known as the "Fan Laws" or "Pump Laws") for pumps/fans are used in hydraulics, hydronics and/or HVAC to express the relationship between variables involved in pump or fan performance (such as head, volumetric flow rate, shaft speed) and power. They apply to pumps, fans, and hydraulic turbines. In these rotary implements ...
The static head of a pump is the maximum height (pressure) it can deliver. The capability of the pump at a certain RPM can be read from its Q-H curve (flow vs. height). Head is useful in specifying centrifugal pumps because their pumping characteristics tend to be independent of the fluid's density. There are generally four types of head:
With the help of these equations the head developed by a pump and the head utilised by a turbine can be easily determined. As the name suggests these equations were formulated by Leonhard Euler in the eighteenth century. [1] These equations can be derived from the moment of momentum equation when applied for a pump or a turbine.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
Specific speed is an index used to predict desired pump or turbine performance. i.e. it predicts the general shape of a pump's impeller. It is this impeller's "shape" that predicts its flow and head characteristics so that the designer can then select a pump or turbine most appropriate for a particular application.