The using situation at present is summarized about the scal for process thick liquid pump. It is reasonable that sealing scheme is composed of secondary impeller and centrifugal block stop seal. Main formulas are dedu...The using situation at present is summarized about the scal for process thick liquid pump. It is reasonable that sealing scheme is composed of secondary impeller and centrifugal block stop seal. Main formulas are deduced and some problems are pointed out on design and calculation of centrifugal block stop seal.展开更多
The computational fluid dynamics(CFD)approach can be used to obtain both internal and external characteristics of centrifugal pumps,and the variations of the hydrodynamic force,the pressure and the torque on the blade...The computational fluid dynamics(CFD)approach can be used to obtain both internal and external characteristics of centrifugal pumps,and the variations of the hydrodynamic force,the pressure and the torque on the blades acquired by the CFD are highly associated with the safety of the pumping system.Based on the CFD simulations,this paper investigates the stopping characteristics of multiple pumps with some pumps being stopped.The 3-D geometric model is built,including all 6 pumps,the valves,the pipes,the tanks and other components,and using the Realizable k-ε turbulence model.The CFD results for the operating points agree well with the results from the theoretical analysis.With some pumps being stopped,the key parameters of the operating pumps would not be stable,with a larger fluctuation;the direction of the hydrodynamic force might be opposite with more than 3 stopped pumps.For the stopped pumps,the maximum reverse values of the discharge and the rotational speed would be larger when fewer pumps are stopped,and could be more than 120%of the rated values,which is dangerous for the pumping system.The CFD results could help understanding the stopping process of multiple pump systems with some pumps being stopped.展开更多
文摘The using situation at present is summarized about the scal for process thick liquid pump. It is reasonable that sealing scheme is composed of secondary impeller and centrifugal block stop seal. Main formulas are deduced and some problems are pointed out on design and calculation of centrifugal block stop seal.
基金Projects supported by the National Natural Science Foundation of China(Grant Nos.51879087,51839008 and 51709087).
文摘The computational fluid dynamics(CFD)approach can be used to obtain both internal and external characteristics of centrifugal pumps,and the variations of the hydrodynamic force,the pressure and the torque on the blades acquired by the CFD are highly associated with the safety of the pumping system.Based on the CFD simulations,this paper investigates the stopping characteristics of multiple pumps with some pumps being stopped.The 3-D geometric model is built,including all 6 pumps,the valves,the pipes,the tanks and other components,and using the Realizable k-ε turbulence model.The CFD results for the operating points agree well with the results from the theoretical analysis.With some pumps being stopped,the key parameters of the operating pumps would not be stable,with a larger fluctuation;the direction of the hydrodynamic force might be opposite with more than 3 stopped pumps.For the stopped pumps,the maximum reverse values of the discharge and the rotational speed would be larger when fewer pumps are stopped,and could be more than 120%of the rated values,which is dangerous for the pumping system.The CFD results could help understanding the stopping process of multiple pump systems with some pumps being stopped.
