Design and Application of Low Flow Steam Siphon Jet Pumps

Author(s):  
Robert A. Leishear ◽  
William M. Bennett ◽  
Jackie Cooper

Low flow steam siphon jet pumps are referred to as rate jets, since these pumps have the ability to control flow rates by varying the steam pressure applied to the jet. The jet pump design consists of several components. Steam inlet piping is connected to a steam nozzle that directs steam into the jet body to provide energy to lift a liquid, or feed. Feed is lifted up through the suction lift piping, where the condensing steam forces the liquid into a diffuser and out of the jet discharge piping. Closed form equations cannot model these jets, and commercial computer models to describe jet performance are still in a state of development. In general, experimental data is required to determine the performance characteristics of this type of jet design. Numerous tests were performed on different jet designs to evaluate the effects of motive steam pressures, suction lift, discharge head, jet dimensions, and the specific gravity of the fluid that is lifted and pumped by the jet. Additionally, the system installation significantly affects the performance of siphon jets, and one such installation was studied.

1950 ◽  
Vol 17 (3) ◽  
pp. 299-309
Author(s):  
J. H. Keenan ◽  
E. P. Neumann ◽  
F. Lustwerk

Abstract A one-dimensional method of analysis of jet pumps or ejectors is presented. The analysis considers mixing of the primary and secondary streams at constant pressure, and mixing of the streams at constant area. For the analytical conditions considered, better performance can be obtained when constant-pressure mixing is employed. A comparison between experimental and analytical results shows good agreement over a broad range of variables. Some experimental data on the length of tube required for mixing of the two streams are presented. A method for jet-pump design is given.


Author(s):  
Francis J. Quail ◽  
Matthew Stickland ◽  
Armin Baumgartner

The regenerative pump is a rotor-dynamic turbomachine capable of developing high heads at low flow rates and low specific speeds. In spite of their low efficiency, usually less than 50%, they have found a wide range of applications as compact single-stage pumps with other beneficial features. The potential of a modified regenerative pump design is presented for the consideration of the performance improvements. In this paper the fluid dynamic behavior of the novel design was predicted using a one-dimensional model developed by the authors. Unlike most one-dimensional models previously published for regenerative pumps, the momentum exchange is numerically computed. Previous one-dimensional models relied on experimental data and correction factors; the model presented in this paper demonstrates an accurate prediction of the pump performance characteristics without the need for correction with experimental data. The validity of this approach is highlighted by the comparison of computed and measured results for two different regenerative pump standards. The pump performance is numerically assessed without the need of correction factors or other experimental data. This paper presents an approach for regenerative pumps using a physically valid geometry model and by resolving the circulatory velocity in the peripheral direction.


1993 ◽  
Vol 115 (4) ◽  
pp. 881-889 ◽  
Author(s):  
R. M. Manglik ◽  
A. E. Bergles

Laminar flow correlations for f and Num are developed based on experimental data for water and ethylene glycol, with tape inserts of three different twist ratios. The uniform wall temperature condition is considered, which typifies practical heat exchangers in the chemical and process industry. These and other available data are analyzed to devise flow regime maps that characterize twisted-tape effects in terms of the dominant enhancement mechanisms. Depending upon flow rates and tape geometry, the enhancement in heat transfer is due to the tube partitioning and flow blockage, longer flow path, and secondary fluid circulation; fin effects are found to be negligible in snug- to loose-fitting tapes. The onset of swirl flow and its intensity is determined by a swirl parameter, Sw=Resw/y, that defines the interaction between viscous, convective inertia, and centrifugal forces. Buoyancy-driven free convection that comes into play at low flow rates with large y and ΔTw is shown to scale as Gr/Sw2≫ 1. These parameters, along with numerical baseline solutions for laminar flows with y = ∞, are incorporated into correlations for f and Num by matching the appropriate asymptotic behavior. The correlations describe the experimental data within ±10 to 15 percent, and their generalized applicability is verified by the comparison of predictions with previously published data.


1977 ◽  
Vol 50 (5) ◽  
pp. 959-968 ◽  
Author(s):  
J. C. Wright ◽  
R. G. Buckles ◽  
J. T. Dunn ◽  
H. M. Leeper ◽  
S. I. Yum

Abstract When drugs are infused, it is often necessary to minimize the volume of fluid delivered. Fluid delivery rates of 1 cm3/h or less are frequently desirable; however, the accurate metering of fluids at such low flow rates to the human body has been difficult to accomplish. The metering devices most commonly used to control flow rate from a constant-pressure source have been micrometer valves, clamped tubes, capillaries, and porous plugs. Each of these devices has specific disadvantages : micrometer valves are expensive and bulky, clamped tubes are not stable for long-term infusion and present a hazard of greatly fluctuating flow rates, capillary tubes are subject to particle blockage and are not adjustable, and porous plugs suffer from lack of adjustability. Recently a valve made of extruded silicone rubber rod with axial holes was reported to yield stable flow rates; it was adjusted by placement in a plastic clamp. A new low-infusion-rate metering system has been developed to overcome the above deficiencies. This system consists of axially aligned polyurethane fibers contained within the lumen of a length of silicone rubber tubing. The fibers fill the lumen to the extent that they are subjected to a compressive hoop stress by the tubing. The assembly represents two elastomeric materials in states of strain, exerting equal and opposite stresses on each other. The elastomeric tubular assembly is contained in a rigid, adjustable, U-shaped enclosure that controls the deformation of the assembly. While other elastomeric materials would be suitable for the elastomeric valving system, we report here on our experience with polyurethane fibers and silicone rubber tubing. These materials were selected for their expected compatibility with most aqueous drugs and their availability.


2021 ◽  
Vol 2(73) (2) ◽  
pp. 22-32
Author(s):  
Denis Panevnyk ◽  

This article analyzes the possibility of increasing the efficiency of using downhole jet pumps by swirling the injected flow. To analyze the peculiarities of the local swirling of injected flow, design and technological parameters in the form of the inclination angle of guiding elements, the diameter of the helical trajectory described by the fluid particles, and the flow rates of the swirling flow are studied. Based on the application of the conservation law of fluid momentum in adjacent jets with a parabolic pressure distribution, equations to determine the pressure characteristic of a jet pump are obtained, taking into account the additional dynamic pressure made by swirling the injected flow. In the process of analyzing the obtained relations, has been set the dependence of the relative pressure growth and the efficiency of the ejection system under the conditions of injected flow swirling on the relative flow rate of a jet pump, and an inversely proportional dependence of the above parameters on its main geometric parameter in the form of the ratio of cross-sectional areas of the mixing chamber and the nozzle.


2005 ◽  
Author(s):  
Yun Whan Na ◽  
J. N. Chung ◽  
Fred Forster

A physical and mathematical model has been developed to predict the two-phase flow and heat transfer in a microchannel with boiling. Based on the above physical model, a total of seven unknowns with corresponding equations resulted. The liquid film thickness, the vapor pressure and the axial heat flow rate have been solved using a fourth-order Runge-Kutta method. The liquid pressure, the vapor and liquid temperatures have been solved using the finite difference method with first order accuracy. The interfacial temperature and pressure have been solved using the root finding method for every mesh point in the axial direction. In addition to the sample calculations that were used to calibrate the model, computations based on the current model were performed to generate results for comparison with Carey’s macro-scale model (Carey, 1992) and with the experimental data of Jiang et al. (2002) where three different mass flow rates of the working fluid were used in the experiment. The comparisons of pressure drops were made for 25 W, 38 W and 58 W of heating with mass flow rates of 2 ml/min, 5 ml/min and 9ml/min, respectively. In general, Carey’s model underpredicted the experimental data by Jiang et al. (2002), especially at the lower flow rates. The calculated results from the current model matched closely with those of Jiang et al. (2002). The main reason for the poor performance of Carey’s model is that it was developed for the macrosystems, where the surface tension and the Marangoni effects are not important.


2021 ◽  
Vol 321 ◽  
pp. 02012
Author(s):  
Miguel Asuaje ◽  
Jens Toteff ◽  
Ricardo Noguera

Despite their low efficiency compared with centrifugal pumps, jet pumps are highly reliable, robust equipment with modest maintenance, ideal for many applications, mainly in the oil & gas industry. Jet pumps are conventionally used to draw fluid from a storage tank in the petrochemical industry or as an artificial lift system to produce oil from a reservoir using energy from the primary fluid. The trunk lines in oil production systems can experience an unfavourable phenomenon due to the fluid's low velocities. In the case of transporting a heavy oil-water mixture with low flow velocities, it could promote oil and water stratification. Due to high viscosity, the stratified oil stick on the pipe,| causing a diameter reduction, resulting in a drop in fluids production and increased energy consumption. Given the virtue of jet pumps, this paper proposes using this equipment as an oil-water transfer pump as an alternative to expensive conventional multiphase pump systems. The jet pump will add fluid into the line, increase the fluid velocities, and promote the homogenous mixture of oil and water. Using ANSYS CFX, the effect of installing a jet pump in a conventional trunkline loop was analysed. Three jet pump configurations were simulated for different driving fluid pressures and compared against a traditional pipeline loop's performance. The first configuration shows a poor performance increasing only until 10% of handling fluids. Conversely, with the improved jet pump configurations rise of the fluid production by 30% has been obtained.


1960 ◽  
Vol 82 (4) ◽  
pp. 947-960 ◽  
Author(s):  
T. W. Van Der Lingen

A compressible flow jet pump theory is evolved which can be more easily interpreted for design purposes than existing theories. It consists of a one-dimensional analysis based on the momentum equation and on complete mixing, used in conjunction with an over-all pressure recovery factor which is found experimentally. Tests on a small jet pump are described and from the results it is shown that the overall pressure recovery factor can be related to a single parameter in the analysis for all operating conditions of each general pump configuration. In this way a general method for the correlation of results and for the design of jet pumps is established.


Author(s):  
Qi Xiao ◽  
Junrong Wang ◽  
Zhenxing Zhao ◽  
Fan Bai ◽  
Zhiguo Wei ◽  
...  

Jet pumps have the advantages in reliable operation, none of moving components and simple construction etc, which makes it applicable in a wide range of industry situations. The cavitation easily occurs within jet pumps and it turns to be a bottleneck for the jet pump design. In this paper, the cavitation flow inside the jet pump would be investigated by 2-D axisymmetric CFD simulations. Firstly, the single liquid phase flow in the jet pump would be simulated and the grid independence test would be carried out. The simulation results show that both the pressure ratio (h) and the efficiency (n) would reach to convergence values with 143,484 meshes, which would be adopted in the following simulations. By comparing with the experimental data of single phase flow in literatures, it was found that the Reynolds stress model offered better predictions. Then the cavitation flow in the jet pump was simulated. It could be found that the cavitation phenomenon trends to occur in the shear layer and the wall detached regions of the throat. At last, the influence of saturated vapor pressure model, the outlet pressure and the nozzle-to-throat clearance would be evaluated. It was found that different from the single phase flow, the optimal nozzle-to-throat clearance would vary with the operation conditions.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Shazia Perveen ◽  
Raziya Nadeem ◽  
Shaukat Ali ◽  
Yasir Jamil

Abstract Biochar caged zirconium ferrite (BC-ZrFe2O5) nanocomposites were fabricated and their adsorption capacity for Reactive Blue 19 (RB19) dye was evaluated in a fixed-bed column and batch sorption mode. The adsorption of dye onto BC-ZrFe2O5 NCs followed pseudo-second-order kinetics (R 2 = 0.998) and among isotherms, the experimental data was best fitted to Sips model as compared to Freundlich and Langmuir isotherms models. The influence of flow-rate (3–5 mL min−1), inlet RB19 dye concentration (20–100 mg L−1) and quantity of BC-ZrFe2O5 NCs (0.5–1.5 g) on fixed-bed sorption was elucidated by Box-Behnken experimental design. The saturation times (C t /C o  = 0.95) and breakthrough (C t /C o  = 0.05) were higher at lower flow-rates and higher dose of BC-ZrFe2O5 NCs. The saturation times decreased, but breakthrough was increased with the initial RB19 dye concentration. The treated volume was higher at low sorbent dose and influent concentration. Fractional bed utilization (FBU) increased with RB19 dye concentration and flow rates at low dose of BC-ZrFe2O5 NCs. Yan model was fitted best to breakthrough curves data as compared to Bohart-Adams and Thomas models. Results revealed that BC-ZrFe2O5 nanocomposite has promising adsorption efficiency and could be used for the adsorption of dyes from textile effluents.


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