Head Net Head is a commonly misused term. Strictly defined, it cannot be directly
measured. It must be calculated from measured values with adjustments made for
the kinetic energy of the water entering and leaving the turbine. Therefore,
the flow and cross-sectional areas of the inlet and outlet waterways must be
considered. Net Head represents the potential energy of the water applied to
the turbine runner, and factors in any losses due to restrictions in the trash
rack, inlet waterway, and discharge waterway.
Piezometric Head is the measured pressure drop across the
turbine runner. Piezometric Head also factors in losses due to restrictions in
the waterway, but it does not accommodate the difference in the kinetic energy
of the water entering and leaving the turbine.
Gross Head is the difference between the upper reservoir
and the lower reservoir. Sometimes the upper water level is measured downstream
of the trash rack, in which case the measurement accommodates restrictions in
the trash rack and inlet waterway, but not restrictions in the discharge water
Operating Head is the term adopted by the IEEE to refer to
the head measurement that is used by a control system, which may be Piezometric
Head, Gross Head, or some modification thereof.
analysis and operation of electricrical generation
resources to achieve the most power and revenue from the
available resource are separated into 5-different areas, or
types of optimization.
Type 1 optimization - Type 2 optimization Type 3 optimization Type 4 optimization Type 5 optimization
Feasability and practicality of a project: Real - A real application that actually works to day and is currently in production. Fantasy - An application that could be possible if we had much better technology. Dream Land - Any practial implementation we can think oif would violate physical laws.
Slacker Descriptive Phrases: Skinner's Constant
- When the test result is not desired, work backwards from the desired
result by creating a factor that, when multiplied by the result
acquired will produce the result desired. Pencil Whipping
- When a periodic maintenance activity is due and the work
time-card arrives, the time card is filled out without doning the work,
in essence, the time-card is "pencil-whipped." Gun-Decking
- is a nautical term for making false claims of achievement or
victories. Term refers to such loose-talk that takes place on the
gun-deck of a naval ship.