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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Troubleshooting and material flow problems:Non steady feeding of pipeline
Low pressure and vacuum:Discharge period and pulsations and Positive pressure systems.
Troubleshooting and material flow problems:With change of distance.
Low pressure and vacuum:Gate lock valves
Fine material:Procedure and Operating point
Control components in a hydraulic system:Pressure control valves
Maintenance and troubleshooting:Prevention of premature hydraulic component failure
Sequencing applications.
INTRODUCTION AND OVERVIE:HEAT TRANSFER
SUMMARY OF INTRODUCTION AND OVERVIE
ENTROPY:MINIMIZING THE COMPRESSOR WORK
HEAT EXCHANGERS:THE OVERALL HEAT TRANSFER COEFFICIENT
FORCED CONVECTION:THERMAL BOUNDARY LAYER
NATURAL CONVECTION:NATURAL CONVECTION OVER SURFACES