Large volume XeCl laser with longitudinal gas flow: experimental results and theoretical analysis

1991 ◽  
Author(s):  
Sarah Bollanti ◽  
Paolo Di Lazzaro ◽  
Francesco Flora ◽  
Gualtiero Giordano ◽  
Tommaso Letardi ◽  
...  
Keyword(s):  
Theoretical Analysis ◽  
Large Volume ◽  
Gas Flow ◽  
Experimental Results ◽  
Xecl Laser

PHOTOINDUCED NONLINEAR OCTUPOLAR POLARIZATION: TRANSIENT AND PERMANENT REGIMES

1996 ◽  
Vol 05 (04) ◽  
pp. 653-670 ◽  
Author(s):  
CÉLINE FIORINI ◽  
JEAN-MICHEL NUNZI ◽  
FABRICE CHARRA ◽  
IFOR D.W. SAMUEL ◽  
JOSEPH ZYSS
Keyword(s):  
Theoretical Analysis ◽  
Second Harmonic ◽  
Experimental Results ◽  
Polar Field ◽  
Rotational Spectrum ◽  
Dual Frequency ◽  
One Dimensional ◽  
Ethyl Violet ◽  
Disperse Red 1 ◽  
Good Agreement

An original poling method using purely optical means and based on a dual-frequency interference process is presented. We show that the coherent superposition of two beams at fundamental and second-harmonic frequencies results in a polar field with an irreducible rotational spectrum containing both a vector and an octupolar component. This enables the method to be applied even to molecules without a permanent dipole such as octupolar molecules. After a theoretical analysis of the process, we describe different experiments aiming at light-induced noncentrosymmetry performed respectively on one-dimensional Disperse Red 1 and octupolar Ethyl Violet molecules. Macroscopic octupolar patterning of the induced order is demonstrated in both transient and permanent regimes. Experimental results show good agreement with theory.

scholarly journals Thermochemical Heat Storage in a Lab-Scale Indirectly Operated CaO/Ca(OH)2 Reactor—Numerical Modeling and Model Validation through Inverse Parameter Estimation

2021 ◽  
Vol 11 (2) ◽  
pp. 682
Author(s):  
Gabriele Seitz ◽  
Farid Mohammadi ◽  
Holger Class
Keyword(s):  
Numerical Model ◽  
Gas Flow ◽  
Reaction Rate ◽  
Heat Storage ◽  
Bulk Material ◽  
Fixed Bed ◽  
Experimental Results ◽  
Fixed Bed Reactor ◽  
Thermochemical Heat Storage ◽  
Speed Up

Calcium oxide/Calcium hydroxide can be utilized as a reaction system for thermochemical heat storage. It features a high storage capacity, is cheap, and does not involve major environmental concerns. Operationally, different fixed-bed reactor concepts can be distinguished; direct reactor are characterized by gas flow through the reactive bulk material, while in indirect reactors, the heat-carrying gas flow is separated from the bulk material. This study puts a focus on the indirectly operated fixed-bed reactor setup. The fluxes of the reaction fluid and the heat-carrying flow are decoupled in order to overcome limitations due to heat conduction in the reactive bulk material. The fixed bed represents a porous medium where Darcy-type flow conditions can be assumed. Here, a numerical model for such a reactor concept is presented, which has been implemented in the software DuMux. An attempt to calibrate and validate it with experimental results from the literature is discussed in detail. This allows for the identification of a deficient insulation of the experimental setup. Accordingly, heat-loss mechanisms are included in the model. However, it can be shown that heat losses alone are not sufficient to explain the experimental results. It is evident that another effect plays a role here. Using Bayesian inference, this effect is identified as the reaction rate decreasing with progressing conversion of reactive material. The calibrated model reveals that more heat is lost over the reactor surface than transported in the heat transfer channel, which causes a considerable speed-up of the discharge reaction. An observed deceleration of the reaction rate at progressed conversion is attributed to the presence of agglomerates of the bulk material in the fixed bed. This retardation is represented phenomenologically by mofifying the reaction kinetics. After the calibration, the model is validated with a second set of experimental results. To speed up the calculations for the calibration, the numerical model is replaced by a surrogate model based on Polynomial Chaos Expansion and Principal Component Analysis.

Implementation of a High-Precision Ultrasonic Rain Gauge

2013 ◽  
Vol 300-301 ◽  
pp. 382-388
Author(s):  
Zhan Wei Xu ◽  
Gui Lin Zheng
Keyword(s):  
Theoretical Analysis ◽  
High Precision ◽  
Rain Gauge ◽  
Experimental Results ◽  
Full Description ◽  
Self Calibration ◽  
Velocity Of Ultrasound

A novel rain gauge based on acoustic self-calibration principle is proposed in the paper. Acoustic self-calibration principle can eliminate the uncertainty of the velocity of ultrasound and achieve accurate measurement of rainfall. The rain gauge not only overcomes the influence on the rainfall measurement under intensive rainfall conditions, but also improves the precision of rain gauge. Plenty of experiments have been done to validate the design. Both theoretical analysis and experimental results show the effectiveness of the rain gauge. A full description of the rain gauge and implementation are presented.

scholarly journals New Topologies of Lossless Grounded Inductor Using OTRA

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Rajeshwari Pandey ◽  
Neeta Pandey ◽  
Sajal K. Paul ◽  
A. Singh ◽  
B. Sriram ◽  
...  
Keyword(s):  
Theoretical Analysis ◽  
Experimental Results ◽  
Pspice Simulation ◽  
Operational Transresistance Amplifier

Two alternate topologies of lossless grounded inductor have been proposed using operational transresistance amplifier (OTRA). Three applications using the proposed inductors are also included. PSPice simulation and experimental results have been included to demonstrate the performance and verify the theoretical analysis.

A Design Model of a New Positive Displacement Rotary Compressor Based on Trochoidal Geometry for High Pressure Applications

2005 ◽  
Author(s):  
Ahmed Abdelwahab
Keyword(s):  
Gas Flow ◽  
Thermodynamic Cycle ◽  
Experimental Results ◽  
Design Model ◽  
Rotary Compressor ◽  
Mechanical Reliability ◽  
High Discharge ◽  
Positive Displacement ◽  
Performance Trends ◽  
Compressor Performance

The desire to achieve high discharge pressures at low manufacturing and maintenance costs has resulted in the development of a number of new positive displacement rotary compressor designs. The proposed design involves a compressor with a trochoidal casing geometry and a rotor orbiting the casing interior. This arrangement generates a varying trapped volume between the rotor and the casing thus providing the necessary compression for the compressor. The major advantage of this design is its inherent simple two-dimensional configuration which makes it a very cheap device to manufacture. Furthermore, the oil-flooded lubrication system used with this design not only acts as a lubricant but also as a coolant to the main gas flow and consequently improves the mechanical reliability of the compressor. This paper presents a complete design model developed to investigate the performance of the compressor. The geometrical, kinematic, and dynamic equations of the casing and rotor are derived. A model of the compressor thermodynamic cycle and gasdynamic performance is presented. A comparison between the developed model and the experimental results of a prototype compressor testing is presented. The comparison shows that the developed model indeed captures the compressor performance trends with considerable accuracy at the design conditions. Deviation between the model and experimental results at the off design conditions is due to inaccuracies in the inlet and exit port loss models at the off design conditions.

Effects of wavelength error and spectral band width on measurement of alkaline phosphatase activity.

1979 ◽  
Vol 25 (3) ◽  
pp. 429-431 ◽  
Author(s):  
R S Schifreen ◽  
R W Burnett
Keyword(s):  
Alkaline Phosphatase ◽  
Theoretical Analysis ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Spectral Band ◽  
Experimental Results ◽  
Band Width ◽  
Published Report ◽  
Two Factors

Abstract We re-examined the effects of wavelength error and spectral band width on the measurement of alkaline phosphatase activity. The methods we studied is relatively insensitive to these two factors, a conclusion we base on both experimental results and theoretical analysis. These findings are in conflict with a recently published report [Lott et al., Clin. Chem. 24, 938 (1978)], and we suggest a possible explanation for this.

scholarly journals 1D–3D Coupling Algorithm of Gas Flow for the Valve System in a Compression Ignition Engine

2021 ◽  
Vol 9 (10) ◽  
pp. 1061
Author(s):  
Kyeong-Ju Kong
Keyword(s):  
Gas Flow ◽  
Flow Analysis ◽  
Emission Control ◽  
Experimental Results ◽  
Exhaust Gas ◽  
Compression Ignition ◽  
Valve System ◽  
Ci Engine ◽  
Control Devices ◽  
Coupling Algorithm

Emission control devices such as selective catalytic reduction (SCR), exhaust gas recirculation (EGR), and scrubbers were installed in the compression ignition (CI) engine, and flow analysis of intake air and exhaust gas was required to predict the performance of the CI engine and emission control devices. In order to analyze such gas flow, it was inefficient to comprehensively analyze the engine’s cylinder and intake/exhaust systems because it takes a lot of computation time. Therefore, there is a need for a method that can quickly calculate the gas flow of the CI engine in order to shorten the development process of emission control devices. It can be efficient and quickly calculated if only the parts that require detailed observation among the intake/exhaust gas flow of the CI engine are analyzed in a 3D approach and the rest are analyzed in a 1D approach. In this study, an algorithm for gas flow analysis was developed by coupling 1D and 3D in the valve systems and comparing with experimental results for validation. Analyzing the intake/exhaust gas flow of the CI engine in a 3D approach took about 7 days for computation, but using the developed 1D–3D coupling algorithm, it could be computed within 30 min. Compared with the experimental results, the exhaust pipe pressure occurred an error within 1.80%, confirming the accuracy and it was possible to observe the detailed flow by showing the contour results for the part analyzed in the 3D zone. As a result, it was possible to accurately and quickly calculate the gas flow of the CI engine using the 1D–3D coupling algorithm applied to the valve system, and it was expected that it can be used to shorten the process for analyzing emission control devices, including predicting the performance of the CI engine.

Influence of Residual Stress on the Thermal Expansion Behavior of Electroformed Nickel Layers

2013 ◽  
Vol 662 ◽  
pp. 511-514
Author(s):  
Yi Chun Liu ◽  
Jia Min Zhang ◽  
Jian Hong Yi
Keyword(s):  
Heat Treatment ◽  
Residual Stress ◽  
Thermal Expansion ◽  
Theoretical Analysis ◽  
Subsequent Heat Treatment ◽  
Experimental Results ◽  
Thermal Expansion Behavior ◽  
Expansion Behavior ◽  
Electroformed Nickel ◽  
The Relationship

Nickel layers with tensile or pressure residual stress were prepared by electroforming technique from two kinds of electrolyte. Subsequent heat treatment was adopted to get the stress released. The coefficients of thermal expansion (CTEs) were measured with a thermal dilatometer and the relationship between residual stress and the measured CTEs was revealed both from experimental results and theoretical analysis.

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