Systems without static head or closed loop systems
The specific energy here is dependent on the frictional head loss which, in turn, is determined by the losses in the pipe system (including throttling valves), and by the combined drive-motor-pump efficiency.
The combined drive-motor-pump efficiency has to be evaluated for each duty point. It is to be noted that the pump efficiency remains approxi mately the same in a system of this type when the speed is changed, whereas the drive-motor efficiency can drop drastically as the load is reduced. If on the other hand, the system curve is changed by changing the setting of a valve, this will change the duty point of the pump and, hence, its efficiency.
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Pumps:Reciprocating pump types
PNEUMATIC SEALS
Gas–solid separation devices:Separation requirements and Separation mechanisms.
Optimizing and up-rating of existing systems:Optimizing conveying conditions.
Review of pneumatic conveying systems:Staged systems and Dual vacuum and positive pressure systems.
Design procedures:Logic diagram for system design
Material property influences:Dense phase sliding bed flow
BASIC HYDRAULICS:USE OF HYDRAULICS
Hydraulic motors:Basic principles
Cartridge logic valves.
Gas laws.
Pressure measurement.
Hydraulic Pumps and Pressure Regulation:Pressure regulation
Actuators:rotary actuators
ENERGY TRANSFER BY HEAT,WORK,AND MASS:HEAT TRANSFER