Acoustic and optical sensing configurations for bulk solids mass flow measurements

2016 ◽  
Author(s):  
Niall O'Mahony ◽  
Trevor Murphy ◽  
Krishna Panduru ◽  
Daniel Riordan ◽  
Joseph Walsh
Keyword(s):  
Mass Flow ◽  
Optical Sensing ◽  
Flow Measurements ◽  
Bulk Solids

scholarly journals Swirl–nozzle interaction experiment: quasi-steady model-based analysis

2021 ◽  
Vol 62 (8) ◽  
Author(s):  
Lionel Hirschberg ◽  
Friedrich Bake ◽  
Karsten Knobloch ◽  
Angelo Rudolphi ◽  
Sebastian Kruck ◽  
...  
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Acoustic Pressure ◽  
Quantitative Information ◽  
Acoustic Response ◽  
Flow Measurements ◽  
Flow Rate Change ◽  
Interaction Experiment ◽  
Swirl Stabilized Combustion

AbstractMeasurements of sound due to swirl–nozzle interaction are presented. In the experiment a swirl structure was generated by means of unsteady tangential injection into a steady swirl-free flow upstream from a choked convergent–divergent nozzle. Ingestion of swirl by the choked nozzle caused a mass-flow rate change, which resulted in a downstream-measured acoustic response. The downstream acoustic pressure was found to remain negative as long as the swirl is maintained and reflections from the open downstream pipe termination do not interfere. The amplitude of this initial acoustic response was found to be proportional to the square of the tangential mass-flow rate used to generate swirl. When the tangential injection valve was closed, the mass-flow rate through the nozzle increased, resulting in an increase of the downstream acoustic pressure. This increase in signal was compared to the prediction of an empirical quasi-steady model, constructed from steady-state flow measurements. As the opening time of the valve was varied, the signal due to swirl evacuation showed an initial overshoot with respect to quasi-steady behavior, after which it gradually decayed to quasi-steady behavior for tangential injection times long compared to the convection time in the pipe upstream of the nozzle. This demonstrates that the acoustic signal can be used to obtain quantitative information concerning the time dependence of the swirl in the system. This could be useful for understanding the dynamics of flow in engines with swirl-stabilized combustion. Graphic abstract

DI-CNG Injector Characterization at Small Energizing Times by Means of Numerical Simulation

2012 ◽  
Author(s):  
Mirko Baratta ◽  
Andrea E. Catania ◽  
Nicola Rapetto ◽  
Alois Fuerhapter ◽  
Matthias Gerlich ◽  
...  
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Research Effort ◽  
Flow Behavior ◽  
Direct Injection ◽  
Time History ◽  
Operating Conditions ◽  
Flow Measurements ◽  
Injection Duration

In the last few years, a significant research effort has been made for developing and enhancing Direct Injection (DI) for compressed natural gas (CNG) engines. Several research projects have been promoted by the European Community (EC) in this field with the objective of finding new solutions for the automotive market and also of encouraging a fruitful knowledge exchange among car manufacturers, suppliers and technical universities. This paper concerns part of the research activity that has been carried out by the Politecnico di Torino, AVL List GmbH and Siemens AG within the EC VII Framework Program (FP) InGAS Collaborative Project (CP), aimed at optimizing the control phase of a new injector for CNG direct injection, paying specific attention to its behavior at small injected-fuel amounts, i.e., small energizing times. The CNG injector which was developed within the research project proved to be suitable to be used in a DI SI engine, featuring a pent-roof combustion chamber head and a bowl in piston, with reference to both homogeneous and stratified charge formation. Fuel flow measurements made by AVL on the four-cylinder engine revealed a good linearity between injection duration and fuel mass-flow rate for injection durations above a reference value. In order to improve the injector characterization at short injection durations, an experimental and numerical activity was designed. More specifically, a multidimensional CFD model of the actual injector geometry was built by Politecnico di Torino, and purposely-designed simulation cases were carried out, in which the needle-lift time-history was defined on the basis of experimental measurements made by Siemens. The numerical model was validated on the basis of experimental data concerning the total injected-fuel amount under different conditions. Then, the model was applied in order to evaluate the dynamic flow characteristic by taking also the inner geometry of the injector valve group into account, so as to establish a correlation to the needle lift measurements done by Siemens for injector characterization. In the paper this dynamic behavior of the injector is analyzed, under actual operating conditions, and its impact on the nozzle injection capability is discussed. The simulation results did not show significant oscillations of the stagnation pressure upstream of the nozzle throat section, and thus the resultant mass-flow rate profile is almost proportional to the needle-lift one. As a consequence, in order to characterize the injector flow behavior in the nonlinear region (short injection duration), the measurement of needle lift is sufficient.

Effects of the properties of bulk solids on the relative performance of polyethylene and stainless steel wall lining materials in mass flow hoppers and other applications

2000 ◽  
Vol 214 (1) ◽  
pp. 53-62 ◽  
Author(s):  
M S A Bradley ◽  
M Bingley ◽  
R J Farnish ◽  
A N Pittman ◽  
G Lee
Keyword(s):  
Stainless Steel ◽  
Mass Flow ◽  
Wall Friction ◽  
Friction Test ◽  
Low Friction ◽  
Flow Discharge ◽  
Flow Problems ◽  
Bulk Solids ◽  
Bulk Solid ◽  
Ultra High Molecular Weight

Reducing the friction between the walls of storage vessels and the bulk solids that they contain is widely known to be beneficial in obtaining more satisfactory flow patterns in such vessels, and to reduce flow problems. In particular, the advantages of low friction in promoting a mass flow discharge pattern are well understood; means of obtaining data to design a hopper for mass flow are also well established. In recent years a number of polyethylene materials have come on to the market, intended for use in lining silos and claimed by their manufacturers to offer low wall friction in comparison with other materials. In this paper, one particular commercial grade of ultra-high molecular weight polyethylene (UHMWPE) material has been tested alongside a commonly used type and finish of ferritic stainless steel. The wall friction has been measured for both materials, with a variety of bulk solid materials and conditions, and the hopper half-angles needed for mass flow computed for each combination. The results show that the UHMWPE material does not always offer a lower friction than the stainless steel; in some cases it offers much lower friction and hence much greater scope for obtaining mass flow discharge. However, in other cases it gives significantly higher friction and is a bad choice for promoting flow. The principal conclusion is that, under certain circumstances, UHMWPE offers substantial advantages over other wall materials. However, this advantage is by no means universal and, if it is to be considered for employment in a hopper design, then a wall friction test should be undertaken. This test should use a sample of the bulk solid to be handled against both the UHMWPE material and other possible materials.

Effect of Condenser Temperature and Speed on one A/C System

2011 ◽  
Vol 314-316 ◽  
pp. 686-690
Author(s):  
Cheng Jun Pan ◽  
Yi Da Tang
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Air Conditioning ◽  
Systems Design ◽  
Test System ◽  
Coefficient Of Performance ◽  
Two Phase ◽  
Flow Measurements ◽  
Air Conditioning System

This study describes the results on the performance of one vehicle air conditioning system. The coefficient of performance, evaporator cooling capacity, compressor power consumption, total mass flow rate, vapor mass flow rate, liquid mass flow rate and oil in circulation, pressures and temperatures of refrigerant at every component (inlets and outlets) are measured and analyzed with the variation of the outside temperatures at the evaporator and condenser, the speed of the compressor, refrigerant charge and oil charge. The systematical experimental results obtained from this real-size test system depict the relations between the above parameters in a vehicle air conditioning system, which constitute a useful source for vehicle air conditioning systems design and analysis. The vapor quality (two-phase flow) measurements realized in this work provide an extremely important tool for diagnosing the system performances.

Experimental and Numerical Investigations on Basic Characteristics of High-Performance Abradable-Aero Hybrid Seal

2014 ◽  
Author(s):  
Yoshihiro Kuwamura ◽  
Kazuyuki Matsumoto ◽  
Hidekazu Uehara ◽  
Hiroharu Ooyama ◽  
Yoshinori Tanaka ◽  
...  
Keyword(s):  
Mass Flow ◽  
Vortex Structure ◽  
High Performance ◽  
Discharge Coefficient ◽  
Labyrinth Seal ◽  
Axial Position ◽  
Leakage Flow ◽  
Flow Measurements ◽  
Wide Range ◽  
Basic Characteristics

As key technologies to improve the performance of steam turbines, various types of high performance seal, such as active clearance control (ACC) seals and leaf seals [1], have been developed by Mitsubishi Heavy Industries, LTD (MHI). In recent years, a new seal concept using an aerodynamic approach called “aero seal” has also been developed, which remarkably reduces the leakage flow while maintaining fin clearances. Furthermore, more robust and higher performance sealing technology called “abradable-aero hybrid seal” which combines the aero seal concept with the abradable seal technology was proposed. The main concept of the aero seal is to control and utilize the vortex structure in the cavities of the labyrinth seal. In the cavities of the aero seal, the locally-controlled flow on the upstream side of the fin tip causes a strong contraction of the leakage flow and reduces the discharge coefficient significantly. This concept allows for a remarkably reduced leakage flow while maintaining fin clearances. Moreover, in order to achieve more robust and higher performance by minimizing the fin clearances, the abradable seal technology was applied to the aero seal concept. However, when the abradable seal is applied, the grooves may be formed on the wall surface of the abradable material due to rubbing of the fin into the abradable material. This situation leads to concern that the groove breaks the effective vortex structure of aero seal and causes negative effects on the seal performance. In this paper, the improved aero seal configuration consisting of slant fins was proposed and it was verified that the reduction in the discharge coefficient of improved aero seal is up to 40% compared to the conventional labyrinth seal. Furthermore, more robust and higher performance sealing technology called “abradable-aero hybrid seal” was proposed and basic characteristics such as the effects of the presence of grooves, the axial position of the fin and seal clearance on the leakage mass flow and the vortex structure were parametrically investigated both experimentally and numerically. In the experiments, not only leakage mass flow measurements but also PIV measurements were carried out in order to visualize the flow patterns in the cavity of the abradable-aero hybrid seal. From the results, it was confirmed that the effective vortex structures were formed even with grooves at various fin positions and the leakage flow can be stably reduced over 40% in a wide range of axial position and reduced by 50% at the optimum position.

Review of Critical Flowmeters for Gas Flow Measurements

1962 ◽  
Vol 84 (4) ◽  
pp. 447-457 ◽  
Author(s):  
B. T. Arnberg
Keyword(s):  
Mass Flow ◽  
Flow Measurement ◽  
Gas Flow ◽  
Flow Measurements ◽  
Flow Rates ◽  
Real Gas ◽  
Discharge Coefficients ◽  
Critical Nozzles ◽  
Mass Flow Rates ◽  
Flow Functions

Critical flowmeters for accurately measuring the mass flow rates of nonreacting real gases were reviewed. Discussions were presented on theoretical flow functions, on parameters for correlating discharge coefficients, and on the importance of real gas properties. The performance characteristics of critical nozzles and orifices of several designs were reviewed. Approaches were discussed to problems which must be researched before the fullest potential of this type of flow measurement can be realized.

Flow Calibration and Error Analysis of Dual-Axis Tracking Trough Solar Collector System

2014 ◽  
Vol 654 ◽  
pp. 262-265
Author(s):  
Jian Ling Deng ◽  
Yong Zhu ◽  
Zi Li Zhou ◽  
Rong Rong Zhai ◽  
Ji Feng Song ◽  
...  
Keyword(s):  
Experimental Study ◽  
Mass Flow ◽  
Solar Collector ◽  
Rotation Speed ◽  
Flow Meter ◽  
Flow Measurements ◽  
Flow Meters ◽  
Collector System ◽  
Ultrasonic Flow Meter

In this paper, a dual-axis tracking trough solar collector system is established, and used to measure and calibrate flow rate at different conditions by using the ultrasonic flow meter and mass flow meter, providing important reference for follow-up experimental study. With the changing of the medium’s temperature and the rotation speed variation of the pump, the two flow meters were used to work together to measure the accurate flow measurements, obtaining the measurement error of the mass flow meter. After that, the reason of error and methods used to reduce the error are analyzed.

Invited Article: Time accurate mass flow measurements of solid-fueled systems

2008 ◽  
Vol 79 (10) ◽  
pp. 101301
Author(s):  
Jordan D. Olliges ◽  
Taylor C. Lilly ◽  
Thomas B. Joslyn ◽  
Andrew D. Ketsdever
Keyword(s):  
Mass Flow ◽  
Accurate Mass ◽  
Flow Measurements
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