Sizing and performance features of rotary and reciprocating positive displacement pumps  

作　　者：Cooper Paul 

机构地区：[1]Fluid Machinery Research,Inc. ,Titusville,New Jersey 08560,USA

出　　处：《排灌机械工程学报》2014年第12期1013-1022,共10页Journal of Drainage and Irrigation Machinery Engineering

摘　　要：An overview of some popular rotary and reciprocating positive displacement( PD) pump types is given with the objective of presenting and comparing the respective sizing relationships and performance features. Reciprocating pumps discussed are the piston and plunger types. Rotary pumps addressed are gear( external and internal),vane,lobe,screw,and liquid ring pumps. To put the relative pump sizes in perspective,attention is fixed on the rotors or reciprocating elements of PD pumps,just as impellers indicate the sizes of rotodynamic pumps. The size of a PD pump is found from a dimensionless combination of displacement flow rate,rotative speed and diameter. The flow rate,head( or pressure rise) and power are related through the component efficiencies. The cavitation coefficient,often close to unity,connects the rotor tip speed or piston speed with the required NPSH,which can also be affected by the pressure rise of the pump due to leakage across the internal clearances. Operational effects due to cavitation,ingestion of gas or abrasives,and viscous and non-Newtonian fluids are discussed.An overview of some popular rotary and reciprocating positive displacement （PD） pump types is given with the objective of presenting and comparing the respective sizing relationships and performance features. Reciprocating pumps discussed are the piston and plunger types. Rotary pumps addressed are gear （external and internal） , vane, lobe, screw, and liquid ring pumps. To put the re- lative pump sizes in perspective, attention is fixed on the rotors or reciprocating elements of PD pumps, just as impellers indicate the sizes of rotodynamic pumps. The size of a PD pump is found from a dimensionless combination of displacement flow rate, rotative speed and diameter. The flow rate, head （or pressure rise） and power are related through the component efficiencies. The cavitation coef- ficient, often close to unity, connects the rotor tip speed or piston speed with the required NPSH, which can also be affected by the pressure rise of the pump due to leakage across the internal clea- rances. Operational effects due to cavitation, ingestion of gas or abrasives, and viscous and non-New-tonian fluids are discussed.

关 键 词：POSITIVE DISPLACEMENT PUMPS ROTARY reciprocating rotor SIZING required NPSH 

分 类 号：S277[农业科学—农业水土工程] TH32[农业科学—农业工程]