Comparison of different models to calculate the viscosity of biogas and biomethane in order to accurately measure flow rates for conformity assessment

AbstractThe study presents an optimised method to correct flow rates measured with a LFE flowmeter pre-set on methane while used for gas mixtures of unknown composition at the time of the measurement. The method requires the correction of the flow rate using a factor based on the viscosity of the gas mixtures once the composition is accurately known. The method has several different possible applications inclusive for the sampling of biogas and biomethane onto sorbent tubes for conformity assessment for the determination of siloxanes, terpenes and VOC in general. Five models for the calculation of the viscosity of the gas mixtures were compared and the models were used for ten binary mixtures and four multi-component mixtures. The results of the evaluation of the different models showed that the correction method using the viscosity of the mixtures calculated with the model of Reichenberg and Carr showed the smallest biases for binary mixtures. For multi-component mixtures, the best results were obtained when using the models of Lucas and Carr.

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Performance Analysis on Variable Injectors to Improve the Internal Velocities and Flow Rates in a Fuel System for Natural Gas Vehicles

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.379.31 ◽

2017 ◽

Vol 379 ◽

pp. 31-38 ◽

Cited By ~ 1

Author(s):

Kwon Se Kim ◽

Doo Seuk Choi

Keyword(s):

Natural Gas ◽

Flow Rate ◽

Total Pressure ◽

Maximum Pressure ◽

Excellent Performance ◽

Flow Rates ◽

Large Size ◽

Velocity Flow ◽

Natural Gas Vehicles

The present study has been attempted to systematically perform a visualizing analysis plan which can improve the flow rate, velocity and mass flow rate as a function of the size of the welding section in the injector as a key for the determination of the injection amount and time of the fuel (CH4) system for natural gas. As the setting conditions for the analysis, a minimum pressure of 2 bar and a maximum pressure of 8 bar were set to be the total pressure values in the case of the inlet, while 0 bar was set for opening drain to represent the state in the atmosphere in the case of the outlet. As a result, the characteristics with an increase in velocity could be affirmed as strong flow separation and eddy current were produced according to the model with a large size of welding section. An excellent performance with an improvement in the performance of velocity flow rate by about 40% could be affirmed in the model where the size of the welding section was designed to be 6 EA.

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Study of Submerged Jet for Suction of Fluid

Journal of Fluids Engineering ◽

10.1115/1.4007266 ◽

2012 ◽

Vol 134 (9) ◽

Author(s):

Sudhakar Subudhi ◽

K. R. Sreenivas ◽

Jaywant H. Arakeri

Keyword(s):

Flow Rate ◽

Coming Out ◽

Particle Image ◽

Lateral Separation ◽

Flow Rates ◽

Submerged Jet ◽

Image Velocimetry ◽

Suction Flow ◽

Source And Sink

This paper deals with the study of a submerged jet for the suction of unwanted fluid. This submerged jet is caused by the fluid coming out from a source. The presence of a sink in front of this source facilitates the suction of the fluid depending upon the source and sink flow rates, the axial and lateral separations of the source and sink, and the angle between the axes of the source and sink. The main purpose is the determination of the sink flow rate for 100% removal of the source fluid as a function of these parameters. The experiments have been carried using a source nozzle 6 mm in diameter and two sizes for the sink pipe diameter: 10 mm and 20 mm. The main diagnostics used are flow visualization using dye and particle image velocimetry (PIV). The dependence of the required suction flow rate to obtain 100% effectiveness on the suction tube diameter and angle is relatively weak compared to the lateral separation.

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Experimental Determination of Special Frequencies With Constant SL (Sound’s Level) in Noise of a Centrifugal Pump That Lead or Lag Due to the Speed Fluctuation

Volume 1: Advanced Energy Systems, Advanced Materials, Aerospace, Automation and Robotics, Noise Control and Acoustics, and Systems Engineering ◽

10.1115/esda2006-95220 ◽

2006 ◽

Cited By ~ 2

Author(s):

M. S. Hashemian Natanzi ◽

H. Rahimzadeh ◽

S. F. Chini

Keyword(s):

Centrifugal Pump ◽

Flow Rate ◽

Sound Level ◽

Shaft Speed ◽

Flow Rates ◽

Speed Fluctuation ◽

Noise Measurements ◽

Speed Fluctuations ◽

Special Frequencies

In this work, an experimental study about the hydrodynamic tonal noise in an industrial centrifugal pump with seven blades has been carried out. Noise measurements on the casing surface have been made for different flow rates with constant shaft speed. The experiment explains that in the frequency domain, the noise of centrifugal pump can be categorized in to two parts. First, as was expected, those frequencies which sound level of them is related to the flow rate and second, those ones that the sound level of them is constant and related to the pump structure. The experiment determines that the frequencies at the second type are so few, and they have correlation with BPF fluctuations. Also with deep notification, it can be considered that these special frequencies, lead or lag due to the speed fluctuations which produced by flow rate changes in nearly constant shaft speed.

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The Determination of In-Situ Film Hole Flow Rates Using a Transient Thermal Inertia Method

Volume 5: Turbo Expo 2003, Parts A and B ◽

10.1115/gt2003-38610 ◽

2003 ◽

Cited By ~ 1

Author(s):

Ronald S. Bunker ◽

Sarah J. Osgood ◽

Nirm V. Nirmalan

Keyword(s):

Flow Rate ◽

Internal Heat ◽

Transient Behavior ◽

Flow Area ◽

Local Flow ◽

Flow Rates ◽

Discharge Coefficients ◽

Thermal Transient

Film hole flow rates are conventionally characterized by a discharge coefficient relating the actual mass flow rate to the theoretical ideal flow rate based upon some measured effective hole diameter or flow area. These discharge coefficients are typically measured on controlled test plates that contain the particular size, shape, and fabrication method for an individual film hole type. Such discharge coefficients are then assumed to apply to all of the in-situ film holes of that type which are machined or formed in the as-fabricated cooled turbine component. The thermal-mechanical analysis of the component is then performed using these assumed values to calculate film hole flow rates. In practice however, every film hole in a cooled airfoil is different due to machine tool wear, surface curvatures, laser drift, coating variations, and local flow supply behavior. A new method has been developed and demonstrated which allows determination of the individual film hole flow rates in-situ for an as-fabricated component, thus avoiding the need for assumed discharge coefficients or highly detailed flow checks. This method uses the thermal transient characteristics of external surface points near an active film hole to determine the flow rate through the hole. An imaging Infrared system is used to record the component response to an induced thermal cooling transient in which the film hole internal heat transfer dominates the local thermal transient behavior. The characteristic of the non-dimensionalized thermal decay is related to the flow rate within each individual film hole using a limited calibration function. This method allows the rapid inspection and quantification of detailed film hole flows for actual parts, which data may then be used in the analysis and health monitoring of parts in operation.

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Determination of the Instantaneous Fuel Flow Rate Out of a Fuel Nozzle

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.3155784 ◽

2009 ◽

Vol 132 (2) ◽

Cited By ~ 2

Author(s):

Tongxun Yi ◽

Domenic A. Santavicca

Keyword(s):

Acoustic Wave ◽

Flow Rate ◽

Acoustic Velocity ◽

Fuel Injector ◽

Pressure Pulsations ◽

Fuel Flow Rate ◽

Flow Rates ◽

Fuel Flow ◽

Fuel Nozzle

Reported is a practical method for accurate and fast determination of the instantaneous fuel flow rate out of a fuel injector. Both gaseous and liquid fuels are considered. Unsteady fuel flow rates introduced into a combustor can be caused by both self-excited pressure pulsations and fuel modulations. During combustion instability, the air flow rate into a combustor also varies in response to pressure pulsations. Accurate determination of the instantaneous fuel and air flow rates is important for both modeling and control of combustion instability. The developed method is based on the acoustic wave theory and pressure measurements at two locations upstream of a fuel injector. This method bypasses the complexities and nonlinearities of fuel actuators and fuel nozzles, and works for systems with slow-time-varying characteristics. Acoustic impedance of a gaseous fuel nozzle is found to be a function of multivariables, including the forcing frequency, the acoustic oscillation intensity, and the mean fuel flow rate. Thus, it is not an intrinsic property of the fuel injector alone. In the present study, sharp tubing bending with almost zero radii is found to have minimal effects on the distribution of 1D acoustic wave. This is probably because vortex shedding and recirculation at tubing corners do not alter the globally 1D characteristics of acoustic wave distribution. Different from the traditional two-microphone method, which determines the acoustic velocity at the middle locations of the two microphones, the present method allows the acoustic velocity, the acoustic mass flux, and the specific acoustic impedance to be determined along the fuel tubing or an air pipe.

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