Hermetically sealed pump
Mechanically simple, hermetically-sealed pump utilizes pumped fluid for lubrication. The rotor, having helical grooves on the outer surface, functions as both a bearing and pump.
Ludwig, L. P.↗
SEARCH · Search NASA
Results for “PUMP SEAL”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Noncontact pump-seals for the space vacuum.
Noncontact pressure generating pump seals for heat space-power systems noting types, characteristics and use in Snap 8 reactor system
Hudelson, J. C.↗
Numerical solutions for the flow and pressure fields in an idealized spiral grooved pumping seal.
Flow and pressure fields for spiral grooved pumping seal with specified groove dimensions and Reynolds number
Renkel, H. E.↗
Numerical analysis of flow and pressure fields in an idealized spiral grooved pumping seal
Computer program for numerical analysis of flow and pressure distribution in idealized spiral grooved pumping seal
Renkel, H. E.↗
Experimental study of pump and seal characteristics of helical groove geometry incorporated in a combined bearing and pump
Pump and seal parameters for helical groove, hermetically sealed pump and bearing rotor
Johnson, R. L.↗
Assessment of two neglected effects in the analysis of an oil pumping ring seal
Many factors have been found to affect the performance of a pumping ring seal. In this paper, two effects (elevated reservoir temperature and rod deformation), both heretofore neglected, are assessed through the use of a thermoelastohydrodynamic numerical model of the pumping ring. Elevated reservoir temperatures are found to result in an increase in the amount of lubricant pumped while deformation of the translating rod is shown to cause a reduction in the lubricant pumped.
Keith, T. G.↗
Operating aspects of an oil pumping ring seal
Past analyses have left several unanswered questions regarding the operation of a pumping ring seal. This paper addresses some of these unresolved problems. In particular, treatment of the film-ring interfacial boundary condition and the return portion of the pumping cycle are numerically investigated. Further a simple model is proposed to determine whether or not the seal operates fully flooded.
Smith, P. J.↗
Thermoelastohydrodynamic analysis of an oil pumping ring seal
The selection and evaluation of the numerical methods used in the thermoelastohydrodynamic analysis of an oil pumping ring seal are described, and the results from test problems used to demonstrate the validity of the implementing computer program are presented. A sampling of predicted pumping ring performance values is compared with existing experimental data. Agreement between prediction and test performance is obtained, yielding detailed information concerning fluid and solid parameters.
Smith, P. J.↗
EHD analysis of and experiments on pumping Leningrader seals
Analysis and design charts have been generated to provide design data for Pumping Leningrader Reciprocating Rod Seals. The analytical treatment divides the seal into three regions: an inlet zone, induced with the use of an expansion ring, a contact zone, and an exit zone. Complete solutions have been obtained by matching elasticity equations with hydrodynamic theory. Experiments, although of a limited nature, did demonstrate the ability of the seal design analysis to provide viable seals.
Eusepi, M. W.↗
Cryogenic seal concept for static and dynamic conditions
Seal rings reduce cryogenic pump seal leakage under static and dynamic conditions. The rings are fitted into annular diaphragms, which are affected by cryogenic pressure and temperature, to move against a mating ring, to increase seal-bearing loads under static conditions.
De Gaetano, E. A.↗
An experimental study on the static and dynamic characteristics of pump annular seals
A test apparatus was constructed and was applied to investigate static and dynamic characteristics of annular seals for turbopumps. The fluid forces acting on the seals were measured for various parameters such as the preswirl velocity, the pressure difference between the inlet and outlet of the seal, the whirling amplitude, and the ratio of whirling speed to spinning speed of the rotor. Influence of these parameters on the static and dynamic characteristics was investigated from the experimental results. As a result, preswirl affects the dynamic characteristics strongly. Especially, the preswirl opposing the rotating direction has a stabilizing role on the rotor system.
Iwatsubo, T.↗
An experimental study on the static and dynamic characteristics of pump annular seals with two phase flow
A new test apparatus is reconstructed and is applied to investigate static and dynamic characteristics of annular seals leaked by two phase flow (gas and liquid) for turbopumps. The fluid forces acting on the seals are measured for various parameters such as void ratio, the preswirl velocity, the pressure difference between the inlet and outlet of the seal, the whirling amplitude, and the ratio of whirling speed to spinning speed of the rotor. Influence of these parameters on the static and dynamic characteristics is investigated from the experimental results. As a result, with regard to the two phase flow, as the void ratio increases, the flow induced force decreases. Another dynamic characteristic of two phase flow is as almost similar as that of the monophase flow.
Iwatsubo, T.↗
J-2X Fuel Pump Impeller Seal Simulations
The J-2X engine was originally designed for the upper stage of the previously cancelled Crew Launch Vehicle. Although the Crew Launch Vehicle was cancelled the J-2X engine, which is currently undergoing hot-fire testing, may be used on future programs. The J-2X engine is a direct descendent of the J-2 engine which powered the upper stage during the Apollo program. Many changes including a thrust increase from 230K to 294K lbf have been implemented in this engine. The rotor-dynamic stability of the fuel turbopump is highly dependent on the tangential velocity of the fluid as it enters the the front face impeller seal. Rotor-dynamic analysis predicts that a much lower tangential velocity will be required for stability than was needed for previous engines. The geometry at the seal entrance for this engine is very complex and vastly different than previous engines. In order to better determine the fluid dynamics and tangential velocity in this seal several CFD simulations were performed. The results of these simulations show that for this seal geometry a great reduction in the tangential velocity is to be expected. The simulations also provided insight into methods that could be employed to drive the swirl velocity to near zero. Unsteady and time-averaged results of several simulations will be presented.
Schmauch, Preston B.↗
Hermetically Sealed Compressor
Proposed hermetically sealed pump compresses fluid to pressure up to 4,000 atm (400 MPa). Pump employs linear electric motor instead of rotary motor to avoid need for leakage-prone rotary seals. In addition, linear-motor-powered pump would not require packings to seal its piston. Concept thus eliminates major cause of friction and wear. Pump is double-ended diaphragm-type compressor. All moving parts sealed within compressor housing.
Holtzapple, Mark T.↗
The effect of inlet swirl on the dynamics of long annular seals in centrifugal pumps
This paper describes additional results from a continuing research program which aims to identify the dynamics of long annular seals in centrifugal pumps. A seal test rig designed at Heriot-Watt University and commissioned at Weir Pumps Research Laboratory in Alloa permits the identification of mass, stiffness, and damping coefficients using a least-squares technique based on the singular value decomposition method. The analysis is carried out in the time domain using a multi-fiequency forcing function. The experimental method relies on the forced excitation of a flexibly supported stator by two hydraulic shakers. Running through the stator embodying two symmetrical balance drum seals is a rigid rotor supported in rolling element bearings. The only physical connection between shaft and stator is the pair of annular gaps filled with pressurized water discharged axially. The experimental coefficients obtained from the tests are compared with theoretical values.
Ismail, M.↗
Rotordynamic Behavior Of Sawtooth-Pattern Damping Seals
Report describes comparative experimental and theoretical study of rotordynamics of several different annular liquid pump seals. Introduces damping seals of new type in which inner surfaces of stators have saw-tooth-cross-section axial grooves interrupted at regular axial intervals by circumferential dams. Teeth of sawtooth patterns directed against rotations in attempt to reduce further asymptotic circumferential velocities of fluids.
Nolan, Steven A.↗
Counter gravity heat pipe techniques
A pump assisted heat pipe may combine the low mass flow rate required of latent heat pipe transfer loops with a hermetically sealed pump to overcome the typical heat pipe capillary limit. This may result in a device with substantially higher heat transfer capacity over conventional pumped single-phase loops, heat pipes, loop heat pipes, and capillary pumped loops with very modest power requirements to operate. Further, one or more embodiments overcome the gravitation limitations in the conventional heat pipe configuration, e.g., when the heat addition zone is above the heat rejection zone, the capillary forces are required to transfer the liquid from the heat rejection zone to the heat addition zone against gravity.
Reid, Robert S.↗
Counter gravity heat pipe techniques
A pump assisted heat pipe may combine the low mass flow rate required of latent heat pipe transfer loops with a hermetically sealed pump to overcome the typical heat pipe capillary limit. This may result in a device with substantially higher heat transfer capacity over conventional pumped single-phase loops, heat pipes, loop heat pipes, and capillary pumped loops with very modest power requirements to operate. Further, one or more embodiments overcome the gravitation limitations in the conventional heat pipe configuration, e.g., when the heat addition zone is above the heat rejection zone, the capillary forces are required to transfer the liquid from the heat rejection zone to the heat addition zone against gravity.
Reid, Robert S.↗