An Experimental Investigation of Several Low-Area-Ratio Water Jet Pumps

1970 ◽  
Vol 92 (1) ◽  
pp. 11-19 ◽  
Author(s):  
N. L. Sanger
Keyword(s):  
Experimental Data ◽  
Experimental Investigation ◽  
Prediction Method ◽  
Area Ratio ◽  
One Dimensional ◽  
Low Area ◽  
High Area ◽  
Jet Pumps ◽  
Experimental Values ◽  
Prediction Parameters

Several low-area-ratio jet pumps were evaluated experimentally in water. Principal geometrical variables investigated were area ratio, throat length, and nozzle spacing. Diffuser geometry was also varied, but to a lesser degree. Experimental values of efficiency and head ratio were compared to a one-dimensional theoretical prediction method previously found to be applicable to moderate and high-area-ratio pumps. Two related cavitation prediction parameters were developed and compared to experimental data.

Low Area Ratio Aircraft Fuel Jet-Pump Performances With and Without Cavitation

1992 ◽  
Vol 114 (4) ◽  
pp. 626-631 ◽  
Author(s):  
M. Marini ◽  
A. Massardo ◽  
A. Satta ◽  
M. Geraci
Keyword(s):  
Prediction Method ◽  
Area Ratio ◽  
Flow Coefficient ◽  
Low Flow ◽  
Low Area ◽  
Aircraft Fuel ◽  
High Area ◽  
Fuel Jet ◽  
Jet Pumps ◽  
Experimental Values

The experimental analysis performed on several small size low area ratio aircraft fuel jet pumps in JP4 is outlined. The variables investigated were area ratio, nozzle and throat diameters, nozzle and suction pressures. The experimental values of head ratio were compared to a one-dimensional theoretical prediction method previously found to be applicable to moderate and high area ratio pumps. The results show the necessity of making some modifications in the model at low flow coefficient values. Measured wall static pressures were also compared with the results of an axisymmetric finite difference turbulent calculation; the comparisons are generally in good agreement. The development of cavitation and related parameters were also investigated. In order to enhance cavitation resistance, which is particularly important in the field of aeronautics, some studies were carried out on two stage jet pumps. The results obtained are outlined and discussed.

An Investigation of Ejector Design by Analysis and Experiment

1950 ◽  
Vol 17 (3) ◽  
pp. 299-309
Author(s):  
J. H. Keenan ◽  
E. P. Neumann ◽  
F. Lustwerk
Keyword(s):  
Experimental Data ◽  
Constant Pressure ◽  
Jet Pump ◽  
Pump Design ◽  
One Dimensional ◽  
Analytical Results ◽  
Constant Area ◽  
Jet Pumps ◽  
Good Agreement

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.

One-Dimensional Performance Prediction of Subsonic Vaned Diffusers

1999 ◽  
Author(s):  
Beat Ribi ◽  
Peter Dalbert
Keyword(s):  
Experimental Data ◽  
Boundary Layer ◽  
Performance Prediction ◽  
Performance Characteristic ◽  
Continuity Equation ◽  
Pressure Rise ◽  
Prediction Method ◽  
Momentum Thickness ◽  
Integral Boundary ◽  
One Dimensional

A simple 1-d-theory to predict the performance of a diffuser using as few empirical factors as possible is presented. The prediction method uses two empirical functions to assess both the pressure recovery and the losses. The functions have been calibrated from experimental data from the company’s standard diffusers. The method is, however, adaptable for any type of subsonic vaned diffusers provided that the empirical functions can be calibrated from measurements. The pressure rise in the diffuser is calculated from the continuity equation taking into account the blockage, while the losses are determined by means of displacement and momentum thickness. These values are calculated at design point from an integral boundary layer calculation. To take into account the influence of flow separation at off-design the calculated displacement and momentum thickness are increased according to empirical functions. When designing a new impeller the method provides a simple way to evaluate the diffuser resulting in the best combination in terms of efficiency and range. It further provides a simple means of estimating the change to be expected in a known stage performance characteristic due to a modification of the diffuser geometry.

One-Dimensional Performance Prediction of Subsonic Vaned Diffusers

1999 ◽  
Vol 122 (3) ◽  
pp. 494-504 ◽  
Author(s):  
Beat Ribi ◽  
Peter Dalbert
Keyword(s):  
Experimental Data ◽  
Boundary Layer ◽  
Performance Prediction ◽  
Continuity Equation ◽  
Pressure Rise ◽  
Prediction Method ◽  
Momentum Thickness ◽  
Dimensional Theory ◽  
Integral Boundary ◽  
One Dimensional

A simple one-dimensional theory to predict the performance of a diffuser using as few empirical factors as possible is presented. The prediction method uses two empirical functions to assess both the pressure recovery and the losses. The functions have been calibrated from experimental data from the company’s standard diffusers. The method is, however, adaptable for any type of subsonic vaned diffusers, provided that the empirical functions can be calibrated from measurements. The pressure rise in the diffuser is calculated from the continuity equation, taking into account the blockage, while the losses are determined by means of displacement and momentum thickness. These values are calculated at design point from an integral boundary layer calculation. To take into account the influence of flow separation at off-design, the calculated displacement and momentum thickness are increased according to empirical functions. When designing a new impeller, the method provides a simple way to evaluate the diffuser, resulting in the best combination in terms of efficiency and range. It further provides a simple means of estimating the change to be expected in a known stage performance characteristic due to a modification of the diffuser geometry.[S0889-504X(00)01703-7]

scholarly journals EXPERIMENTAL INVESTIGATION INTO FIRE RESISTANCE OF HC‐FST COLUMNS UNDER AXIAL COMPRESSION

2007 ◽  
Vol 13 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Žygimantas Blaževičius ◽  
Audronis Kazimieras Kvedaras
Keyword(s):  
Experimental Data ◽  
Experimental Investigation ◽  
Fire Resistance ◽  
Research Work ◽  
Tubular Columns ◽  
Test Parameters ◽  
Wide Range ◽  
Axially Loaded ◽  
Experimental Values ◽  
Stub Columns

A certain amount of analytical methods for determining fire resistance of concrete filled steel tubular columns are developed. Mostly those methods refer to or have as an origin the data about the results of real experiments. The research work on this kind of composite column behaviour under fire conditions with a wide range of different parameters measuring was performed. The behaviour of 16 axially loaded HC‐FST (hollow concrete filled steel tubular) columns without fire protection under conditions similar to ISO‐834 fire and under normal conditions was experimentally investigated and the results are presented in this paper. The experimental values of fire resistance were measured and the failure mode was determined for 4 axially loaded columns. And for the comparison of test parameters, 4 axially loaded HC‐FST columns were tested under normal conditions. In addition, 8 hollow concrete‐filled steel tubular stub columns and 4 hollow concrete tubular stub columns under normal conditions were tested. The final objective was to prepare experimental data for analysis and to find some analytical dependence between test parameters with the most significant influence on the fire results of HC‐FST columns.

A CONTRIBUTION TO THE QUALITATIVE GC ANALYSIS OF SOME NON-CHLORINATED XENOBIOTIC CHEMICALS IN WASTE WATERS

1994 ◽  
Vol 30 (3) ◽  
pp. 91-93 ◽  
Author(s):  
Biljana D. Škrbic ◽  
Mirjana B. Vojinovic-Miloradov
Keyword(s):  
Experimental Data ◽  
Stationary Phases ◽  
Retention Indices ◽  
Waste Waters ◽  
Gc Analysis ◽  
Experimental Values ◽  
Xenobiotic Chemicals

Gas chromatographic unified retention indices of some chlorinated xenobiotic chemicals, as pollutants in waste waters, on OV-101 and SE-30 stationary phases are presented. These values agree well with the corresponding experimental values used in the statistical treaunent of the experimental data.

scholarly journals An Additive Model to Predict the Rheological and Mechanical Properties of Polypropylene Blends Made by Virgin and Reprocessed Components

Recycling ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 2
Author(s):  
Francesco Paolo La Mantia ◽  
Maria Chiara Mistretta ◽  
Vincenzo Titone
Keyword(s):  
Experimental Data ◽  
Mechanical Properties ◽  
Additive Model ◽  
Industrial Process ◽  
Theoretical Predictions ◽  
Experimental Values ◽  
Polypropylene Blends ◽  
Polypropylene Sample

In this work, an additive model for the prediction of the rheological and mechanical properties of monopolymer blends made by virgin and reprocessed components is proposed. A polypropylene sample has been reprocessed more times in an extruder and monopolymer blends have been prepared by simulating an industrial process. The scraps are exposed to regrinding and are melt reprocessed before mixing with the virgin polymer. The reprocessed polymer is, then, subjected to some thermomechanical degradation. Rheological and mechanical experimental data have been compared with the theoretical predictions. The results obtained showed that the values of this simple additive model are a very good fit for the experimental values of both rheological and mechanical properties.

scholarly journals Correction and accuracy improvement of non-parallel shear zone model

2018 ◽  
Vol 207 ◽  
pp. 02002
Author(s):  
Yaoke Wang ◽  
Meng Kou ◽  
Wei Ding ◽  
Huan Ma ◽  
Liangshan Xiong
Keyword(s):  
Experimental Data ◽  
Cutting Force ◽  
Shear Zone ◽  
Coordinate Transformation ◽  
Chip Thickness ◽  
Zone Model ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Experimental Values ◽  
1045 Steel

When applying the non-parallel shear zone model to predict the cutting process parameters of carbon steel workpiece, it is found that there is a big error between the prediction results and the experimental values. And also, the former approach to obtain the relevant cutting parameters of the non-parallel shear zone model by applying coordinate transformation to the parallel shear zone model has a theoretical error – it erroneously regards the determinant (|J|) of the Jacobian matrix (J) in the coordinate transformation as a constant. The shape of the shear zone obtained when |J| is not constant is drew and it is found that the two boundaries of the shear zone are two slightly curved surfaces rather than two inclined planes. Also, the error between predicted values and experimental values of cutting force and cutting thrust is slightly smaller than that of constant |J|. A corrected model where |J| is a variable is proposed. Since the specific values of inclination of the shear zone (α, β), the thickness coefficient of the shear zone (as) and the constants related to the material (f0, p) are not given in the former work, a method to obtain the above-mentioned five constants by solving multivariable constrained optimization problem based on experimental data was also proposed; based on the obtained experimental data of AISI 1045 steel workpiece cutting force, cutting thrust, chip thickness, the results of five above-mentioned model constants are obtained. It is found that, compared with prediction from uncorrected model, the cutting force and cutting thrust of AISI 1045 steel predicted by the corrected model with the obtained constants has a better agreement with the experimental values obtained by Ivester.

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