Theoretical Analysis of Experimentally Observed Perplexing Calibration Characteristics of Ball-in-Vortex Flow-Meter

2005 ◽  
Vol 127 (5) ◽  
pp. 1021-1028
Author(s):  
S. P. Mahulikar ◽  
S. K. Sane
Keyword(s):  
Mathematical Model ◽  
Theoretical Analysis ◽  
Frictional Force ◽  
Flow Measurement ◽  
Vortex Flow ◽  
Sharp Change ◽  
Mathematical Form ◽  
Flow Meter ◽  
Rotating Sphere ◽  
The Mathematical Model

This investigation analyzes the calibration nonlinearity of the ball-in-vortex flow-meter, designed to work on the principle of a rotating sphere in and due to a vortex flow. The comparison of this flow-meter reading with the standard flow-meter indicates the existence of different calibration regimes, bifurcated by a sharp change in slope of the calibration curve. Based on the governing mechanics of this flow-meter, this paper explains this nonlinearity, and proposes its mathematical form. In particular, the bifurcation in calibration characteristics is attributed to the change in the surface contact frictional force, due to translation of the ball. The mathematical model captures the various calibration regimes associated with this translation, from one plane of rotation in the flow-meter to another, or from one periphery to another. Thus, calibration nonlinearity of this flow-meter can be fully comprehended through its governing mechanics, and harnessed for flow measurement.

Attenuation of pulsations in the reciprocating compressor piping system with an elbow-shaped surge tank

2018 ◽  
Vol 233 (5) ◽  
pp. 1677-1689
Author(s):  
Quyang Ma ◽  
Guoan Yang ◽  
Mengjun Li
Keyword(s):  
Mathematical Model ◽  
Theoretical Analysis ◽  
Frequency Analysis ◽  
Transfer Matrix Method ◽  
Piping System ◽  
Pulsation Frequency ◽  
Reciprocating Compressor ◽  
Pressure Pulsations ◽  
Surge Tank ◽  
The Mathematical Model

An elbow-shaped surge tank is proposed to suppress the pressure pulsations. The transfer matrix method was developed and the mathematical model was established to predict the distribution of pressure pulsations in the piping system (on which a surge tank was already installed) with an elbow-shaped surge tank. Simulation work of the whole piping system was performed. The results show that the elbow-shaped surge tank has good performance to attenuate the pressure pulsations. The frequency analysis shows that the amplitude for the first pulsation frequency is attenuated to a low level. The impulse response was analyzed to examine the efficiency of suppressing pulsations by using the suppressor. The theoretical analysis showed that there exists the optimal suppression performance when setting the distance between the elbow-shaped surge tank and the existing one. Meanwhile, modifying the ratio of length to diameter with a fixed surge volume could also impact the pressure pulsations. The analysis results can be used as a reference in designing and installing the elbow-shaped surge tank.

A Model for Drilled Cooling in the Valve Bridge of Cylinder Head

2011 ◽  
Vol 52-54 ◽  
pp. 338-342
Author(s):  
Xiao Liu ◽  
Wei Zheng Zhang ◽  
Chang Hu Xiang
Keyword(s):  
Heat Transfer ◽  
Mathematical Model ◽  
Heat Transfer Coefficient ◽  
Diesel Engine ◽  
Theoretical Analysis ◽  
Transfer Coefficient ◽  
Cylinder Head ◽  
3D Model ◽  
Numerical Study ◽  
The Mathematical Model

To evaluate the efficiency of drilled cooling in the valve bridge of cylinder head, theoretical analysis for the drilled cooling is carried out, and a mathematical model for the enhanced cooling is presented based on a simplified 3D model. The mathematical model is validated by numerical study on the heat transfer with and without drilled cooling, which is carried out through fluid-solid coupling. The correlation between the velocity in the drilled passage and heat transfer coefficient was also analyzed. The results can be used to solve the heat transfer in enhanced diesel engine.

A Multistable Generalized Meminductor with Coexisting Stable Pinched Hysteresis Loops

2020 ◽  
Vol 30 (02) ◽  
pp. 2050023
Author(s):  
Fang Yuan ◽  
Yue Deng ◽  
Yuxia Li
Keyword(s):  
Mathematical Model ◽  
Theoretical Analysis ◽  
Hysteresis Loops ◽  
The Mathematical Model ◽  
Pinched Hysteresis

A multistable local active meminductor emulator is proposed in this paper. The mathematical model of the emulator circuits is established. Different periodic stimuli are applied to the presented emulators and coexisting stable pinched hysteresis loops are obtained. The results obtained by experimental equips are consistent with the theoretical analysis, which indicates that the proposed emulators can work as a meminductor.

scholarly journals Research on the Influence of Switching Frequency on Low-Frequency Oscillation in the Voltage-Controlled Buck-Boost Converter

2011 ◽  
Vol 2011 ◽  
pp. 1-15 ◽  
Author(s):  
Faqiang Wang ◽  
Xikui Ma
Keyword(s):  
Mathematical Model ◽  
Theoretical Analysis ◽  
Low Frequency ◽  
Boost Converter ◽  
Switching Frequency ◽  
Frequency Oscillation ◽  
Low Frequency Oscillation ◽  
Matlab Simulink ◽  
Averaged Model ◽  
The Mathematical Model

The influence of switching frequency on the low-frequency oscillation in the voltage-controlled buck-boost converter is studied in this paper. Firstly, the mathematical model of this system is derived. And then, a glimpse at the influence of switching frequency on the low-frequency oscillation in this system by MATLAB/Simulink is given. The improved averaged model of the system is established, and the corresponding theoretical analysis is presented. It is found that the switching frequency has an important influence on the low-frequency oscillation in the system, that is, the low-frequency oscillation is easy to occur when the switching frequency is low. Finally, the effectiveness of the improved averaged model and the theoretical analysis are confirmed by circuit experiment.

Theoretical Study on the Wetting Length in Triangle Wetting Region of Rectangular Microgrooves

2011 ◽  
Author(s):  
Tao Wang ◽  
Xuegong Hu ◽  
Chaohong Guo ◽  
Xuelei Nie ◽  
Ningning Xie
Keyword(s):  
Mathematical Model ◽  
Heat Flux ◽  
Theoretical Analysis ◽  
Tilt Angle ◽  
Heat Sink ◽  
Theoretical Study ◽  
Geometric Dimension ◽  
The Mathematical Model ◽  
The Relationship ◽  
Working Liquid

The mathematical model is established in this article to describe the relationship between the wetting length of working liquid in the triangular wetting region of rectangular capillary microgrooves and the geometric dimension, tilt angle, type of working liquid and heat flux when heating the back of microgrooves heat sink. The model supposes that the vapour-liquid interface of meniscus is quadratic parabola but not arc. The predictions from the theoretical analysis are successfully compared with the experimental results.

scholarly journals Mathematical Model for Reducing the Concentration of a Chemical Substance Applicable in the Procedures of Plasmatic Treatment

2019 ◽  
Vol 70 (4) ◽  
pp. 1298-1301
Author(s):  
Ciprian Mihai Gindac ◽  
Ovidiu Horea Bedreag ◽  
Laura Alexandra Nussbaum ◽  
Iulia Bianca Micu Serbu ◽  
Roxana Folescu ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Laboratory Data ◽  
Chemical Substance ◽  
The Body ◽  
Chemical Model ◽  
Mathematical Form ◽  
Initial Concentration ◽  
Plasma Loss ◽  
The One ◽  
The Mathematical Model

The objective was to study the correlation between the mathematical form of a chemical that we want to lower its initial concentration by the regressive method and the purging of the body�s toxic present chemicals that need to be eliminated. We developed a chemical model, by which, to a given volume, with a certain (X - concentration %) dissolved substance in a container, the initial solvent, without solvit, is added (concentration 0%) with an equal rhythm to the one that is lost from the used container. The solution that will be lost will contain less and less concentrations of solvit, compared to the initial value X%. At the same time, the concentration of our chemical model will decrease. We applied a regressive mathematical formula to this model in order to calculate the concentration in the container in each moment. At the same time, we conducted treatment sessions in patients in which certain substances need to be eliminated, a procedure that complies with the described chemical model. We have demonstrated that at the same volume of 0% solvit wash, the substance purging with X% concentration is more effective, if the procedure starts with an initial loss of concentrated substance, with ulterior volume replacement. Laboratory data confirms the mathematical model in patients who started the procedure with plasma loss. The developed chemical model demonstrates that the initial loss of substance, hastens the decrease of the initial concentration, especially as the loss is higher at the beginning of the procedure if we use the same replacement volume without the substance in the initial solution. This model can be applied in plasma treatment methods in order to study the patient�s safety and the amount of plasma the patient can lose at the beginning.

A New Mathematical Model to Calculate DC Transmission System’s Operating Parameters

2012 ◽  
Vol 614-615 ◽  
pp. 988-995
Author(s):  
Rong Yan Shang ◽  
Yin Chen ◽  
Chang Qing Peng
Keyword(s):  
Mathematical Model ◽  
Theoretical Analysis ◽  
Decomposition Method ◽  
Theoretical Calculations ◽  
Transmission System ◽  
Operating Parameters ◽  
Fourier Decomposition ◽  
Calculation Results ◽  
And Control ◽  
The Mathematical Model

To study the DC transmission system, and control it in real-time, many researchers make models based on the Fourier decomposition method. However, their calculations are not very precise. In this paper, a new mathematical model for the DC transmission system was build, by use of the Fourier formulas to decompose the current on the converter transformer’s valve side. Formulas for the operating parameters of both rectifier station and inverter station were derived, and the effects of the harmonics were considered. Results from theoretical calculations and experimental collection show that waveforms of the operating parameters are very similar. Even the experimental waveforms change a little, the calculation results can reflect the change clearly, which fully prove that the theoretical analysis is correct and the mathematical model is accurate.

Sign in / Sign up

Export Citation Format

Share Document