Sterilization of Food in Containers with an End Flat Against a Retort Bottom: Numerical Analysis and Experimental Measurements

1984 ◽  
Vol 49 (2) ◽  
pp. 461-467 ◽  
Author(s):  
D. NAVEH ◽  
I. J. PFLUG ◽  
I. J. KOPELMAN
Keyword(s):  
Numerical Analysis ◽  
Experimental Measurements

scholarly journals Frequency multiplexed coherent φ-OTDR

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hannah M. Ogden ◽  
Matthew J. Murray ◽  
Joseph B. Murray ◽  
Clay Kirkendall ◽  
Brandon Redding
Keyword(s):  
Numerical Analysis ◽  
Pulse Train ◽  
State Of The Art ◽  
Average Power ◽  
Comprehensive Analysis ◽  
Experimental Measurements ◽  
Rayleigh Backscattering ◽  
Sensor Performance ◽  
Sensor Platform ◽  
Lower Noise

AbstractWe present a comprehensive analysis of a frequency multiplexed phase-measuring φ-OTDR sensor platform. The system uses a train of frequency-shifted pulses to increase the average power injected into the fiber and provide a diversity of uncorrelated Rayleigh backscattering measurements. Through a combination of simulations, numerical analysis, and experimental measurements, we show that this approach not only enables lower noise and mitigates interference fading, but also improves the sensor linearity. We investigate the sensor dependence on the length of the pulse train and characterize the sensor performance as a function of range, demonstrating operation from 1 to 50 km. Despite its relative simplicity, this platform enables state-of-the-art performance, including low crosstalk, high linearity, and a minimum detectable strain of only 0.6 p$$\varepsilon /\sqrt{\text{Hz}}$$ ε / Hz in a 10 km fiber with 10 m spatial resolution and a bandwidth of 5 kHz.

scholarly journals Investigation of dynamics and power needs for container unloading from ship process

2021 ◽  
Vol 24 (1) ◽  
pp. 89-99
Author(s):  
Jolanta Janutėnienė ◽  
Marijonas Bogdevičius ◽  
Valdas Jankūnas ◽  
Jūratė Janutėnaitė-Bogdanienė ◽  
Arūnas Andziulis ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Numerical Analysis ◽  
Contact Forces ◽  
Experimental Measurements ◽  
Operational Problem ◽  
Frictional Forces ◽  
Power Needs

The operational problem of container unloading from the ship is analyzed in this paper. Dynamic “crane-cargo-ship” system was investigated, and a mathematical model was created. In the model, the gap between the container and the ship’s cargo hold, the mass of the cargo, the container’s center of the mass, and the frictional forces that may occur during lifting from the cargo hold were estimated. Numerical analysis of the system was performed. Results of numerical analysis were compared with experimental measurements of containers unloading process in port. Requirement of lifting power was modelled depending on mass of cargo. Additional power needs in case of contact forces between container and wall of the ship’s cargo hold were calculated. Rational lifting conditions could be deduced using a created mathematical model and the reliability of the container and cargo during lifting could be deduced.

scholarly journals Experimental, analytical and numerical analysis of voltage distribution along the cap-and-pin insulators

2020 ◽  
Vol 4 (2) ◽  
Author(s):  
Mladen Banjanin
Keyword(s):  
Mathematical Model ◽  
Numerical Analysis ◽  
Electrostatic Field ◽  
Field Model ◽  
Experimental Measurements ◽  
Voltage Distribution ◽  
Specialized Software ◽  
The Earth ◽  
Good Agreement ◽  
Linear Voltage

This paper deals with the experimental, analytical and numerical analysis of voltage distribution along the cap-and-pin insulators. Five different insulators strings are analyzed, consisting of two, three, four, five and six cap-and-pin U40BL glass disc insulators. Experimental measurements are performed in the high voltage laboratory at the Faculty of Electrical Engineering East Sarajevo. Measurement of the voltage distribution along the disc insulators is performed by using measuring sphere gap. Analytical calculations are performed by using mathematical model which considers parasite self-capacitances of disc insulators, as well as their parasite capacitances to the earth and to the phase conductor. Calculations of the parasite capacitances values are performed and optimum values which lead to the minimum difference between measured and calculated results are suggested. Numerical analyses of the non-linear voltage distribution are performed by using electrostatic field model in software Comsol Multyphisics. 2D axisymmetric models of the cap-and-pin insulators are developed. Despite the measuring configuration is not suitable for numerical analysis, relatively good agreement between the measured results and results calculated by using specialized software are achieved.

Calculation of the Pressure Gradient, Velocity, and Wall Shear in Arteries for a Given Flow Rate

2011 ◽  
Vol 2 (2) ◽  
Author(s):  
A. S. Abdalla Wassf Isaac
Keyword(s):  
Fourier Series ◽  
Numerical Analysis ◽  
Pressure Gradient ◽  
Mathematical Models ◽  
Flow Rate ◽  
Input Data ◽  
Inverse Method ◽  
Experimental Measurements ◽  
Artery Flow

The aim of this study was to build an inverse method, which best fits a model of artery flow and experimental measurements, and to provide a good quality of input data for the mathematical models so that proper inferences can be drown from the models. Using numerical analysis to convert the flow rate profiles to the pressure gradient profiles, a Fourier series for this profile (∂p/∂z−t) is then obtained. The results obtained were compared with pressure gradient profile in Fourier series.

Study on the Air-Side Heat Transfer and Pressure Drop for Fin-Tube Heat Exchangers

2002 ◽  
Author(s):  
Ji Hwan Jeong ◽  
Keun Sun Chang ◽  
Young Chel Kweon ◽  
Sang Jae Lee ◽  
Min Kyu Lee
Keyword(s):  
Heat Transfer ◽  
Numerical Analysis ◽  
Pressure Drop ◽  
Heat Exchangers ◽  
Unit Area ◽  
Numerical Results ◽  
Experimental Measurements ◽  
Air Velocity ◽  
Fin Tube ◽  
Good Agreement

Experimental measurements and numerical analysis have been carried out in order to investigate performances of air-side heat transfer and pressure drop for six types of heat exhcangers with various fin shapes. An air-enthalpy calorimeter is used in this work. Numerical analysis shows a good agreement with experimental measurements. Measurements for six types of heat exchangers at various air-velocity are compared with each other. Heat transfer per unit area appears to be nearly the same in the range of 0.7~0.9 m/s while it varies within 3% at 1.5 m/s. The numerical results show that most of heat transfer takes place through fins for all types and majority of heat transfer happens from the 1st row.

scholarly journals Prerequisites for Increasing the Axle Load on Railway Tracks in the Czech Republic

10.14311/1063 ◽  
2008 ◽  
Vol 48 (6) ◽  
Author(s):  
M. Lidmila ◽  
L. Horníček ◽  
H. Krejčiříková ◽  
P. Tyc
Keyword(s):  
Czech Republic ◽  
Numerical Analysis ◽  
Experimental Measurements ◽  
The Czech Republic ◽  
Railway Tracks ◽  
Axle Loads

This paper deals with problems of increasing the axle load on Czech Railways (ED) tracks to 250 kN or 300 kN, respectively. The results of a numerical analysis of the effects of increased axle loads on the track bed structure were verified by experimental measurements carried out on track bed construction models in an experimental box on a 1:1 scale. The results of the research are applicable for routine use on ED. 

Rotor Dynamics Analysis and Testing of a Turbomolecular Pump Rotor-Bearing System

2011 ◽  
Author(s):  
Chih-Neng Hsu ◽  
Hsiao-Wei D. Chiang ◽  
Yu-Meng Huang ◽  
Ying-Chia Fu ◽  
Kuo-Hsun Hsu ◽  
...  
Keyword(s):  
Finite Element ◽  
Numerical Analysis ◽  
Dynamic Characteristics ◽  
Critical Speed ◽  
Experimental Measurements ◽  
Pump System ◽  
Pump Rotor ◽  
Turbomolecular Pump ◽  
Rotor Bearing ◽  
Bearing System

This study is focused on the dynamic characteristics of a vertical turbomolecular pump (TMP) rotor-bearing system. The research methods can be divided into two parts, which are numerical analysis and experimental measurements. In numerical analysis, we use the finite element analysis software DyRoBeS and ANSYS to construct a two- and three-dimensional models of the rotor-bearing system. In the analysis process, by using the pump system assembly testing data, we can verify the rotor-bearing system finite element models under different boundary conditions. Next, we calculate the Campbell diagram to study the dynamic characteristics of the rotor-bearing system, and to compare with the experimental results to verify the models. Finally, we found the relationship between the rotor critical speed and the bearing stiffness in order to study the design of the molecular pump rotor and the bearing system. Experimental measurements were divided into two parts: static modal tests and dynamic measurements. Static modal tests can provide the natural frequencies of the rotor-bearing system. Waterfall diagrams of the dynamic tests can measure the pump system critical speed from zero speed up to the working speed crossing, and to insure that the pump working speed is far from the critical speed of at least 10% in the safe margin. In summary, the results of the experimental measurements and numerical analysis can provide the basis for the design tool for turbomolecular pump rotor-bearing system in order to identify and prevent pump vibrations.

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