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.
Related posts:
Case studies:Variable speed drive on a circulating pump in a batch process
Selection process retrofitting to existing equipment:Retrofitting a motor mounted VFD
PNEUMATIC SEALS
Particle degradation:Pneumatic conveying data and Experimental details
Pressure and flow:Pressure in fluids
Low pressure and vacuum:Gate lock valves
Design procedures:The use of equations in system design and Logic diagram for system design.
ROUBLESHOOTING PNEUMA TIC CIRCUITS:PNEUMATIC SYSTEM COMPONENT fAILURE MODES
MAINTENANCE OF HYDRAULIC SYSTEMS:ROOT CAUSE FAILURE ANALYSIS
ACTUATORS:Gear-Type Motors
HYDRAULIC FLUIDS:HYDRAULIC FLUID SAMPLING
FORCES IN LIQUIDS:TRANSMISSION OF FORCE THROUGH LIQUIDS.
Service units.
RADIATION HEAT TRANSFER: DIFFUSE, GRAY SURFACES
HEAT EXCHANGERS:TYPES OF HEAT EXCHANGERS