An Experimental Study of Ammonia Receiver Geometries for Dish Concentrators

2012 ◽  
Vol 134 (4) ◽  
Author(s):  
Rebecca Dunn ◽  
Keith Lovegrove ◽  
Greg Burgess ◽  
John Pye
Keyword(s):  
Experimental Study ◽  
Energy Conversion ◽  
Experimental Evaluation ◽  
Second Generation ◽  
Experimental Results ◽  
Efficiency Gain ◽  
Efficiency Gains ◽  
Conical Shape ◽  
Chemical Efficiency ◽  
National University

This paper presents experimental evaluation of ammonia receiver geometries with a 9 m2 dish concentrator. The experiments involved varying the geometric arrangement of reactor tubes in a thermochemical reactor built from a series of tubes arranged in a conical shape inside a cavity receiver. Differences in conical arrangement were found to affect the efficiency of energy conversion. The solar-to-chemical efficiency gain obtained by varying the receiver geometry was up to 7% absolute. From this, it is apparent that geometric optimizations are worth pursuing since the resulting efficiency gains are achieved with no increase in costs of manufacture for receivers. The experimental results and methodology can be used when developing receivers for larger dish concentrators, such as the second generation 500 m2 dish concentrator developed at the Australian National University.

scholarly journals Experimental Evaluation of 79 and 300 GHz Radar Performance in Fire Environments

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 439
Author(s):  
Aleksandr Bystrov ◽  
Liam Daniel ◽  
Edward Hoare ◽  
Fatemeh Norouzian ◽  
Mikhail Cherniakov ◽  
...  
Keyword(s):  
Experimental Study ◽  
Water Vapour ◽  
Experimental Evaluation ◽  
Theoretical Calculations ◽  
Video Camera ◽  
Experimental Results ◽  
Radar Signal ◽  
Signal Attenuation ◽  
Millimetre Wave ◽  
In Fire

This paper presents an experimental study of the propagation of mm-wave/low-THz signals in the frequency ranges of 79 and 300 GHz through fire. Radar performance was investigated in various real scenarios, including fire with strong flame, dense smoke and water vapour. A stereo video camera and a LIDAR were used as a comparison with other common types of sensors. The ability of radars to enable the visibility of objects in fire environments was proven. In all scenarios, the radar signal attenuation was measured, and in the case of steam was compared with theoretical calculations. The analysis of the experimental results allows us to conclude that there are good prospects for millimetre wave and Low Terahertz radar in the field of firefighting imaging equipment.

scholarly journals Experimental evaluation of an industrial technique for the approximation of software functional size

2013 ◽  
Vol 10 (3) ◽  
pp. 1459-1474
Author(s):  
Khaled Almakadmeh ◽  
Alain Abran
Keyword(s):  
Experimental Study ◽  
Experimental Evaluation ◽  
Experimental Results ◽  
Functional Requirements ◽  
Iso Standards ◽  
Requirements Specifications ◽  
High Level ◽  
Functional Size

The Early & Quick sizing techniques, built based on ISO standards, have been proposed to derive an early approximation of software functional size when only high-level and incomplete requirements specifications are available. In the literature, there is a lack of research to evaluate the performance of such approximation sizing methods. This paper presents an experimental study to evaluate their reproducibility and accuracy. The experimental results show both poor reproducibility and large inaccurate approximations. In particular, the analysis of the findings indicates that the practitioners could not classify the functional requirements specifications in accordance to their levels of granularity using the rules and the concepts of the Early & Quick COSMIC technique.

scholarly journals Experimental study of the $ \gamma p \rightarrow K^{0}\Sigma^{+}$, $ \gamma n \rightarrow K^{0} \Lambda$, and $ \gamma n \rightarrow K^{0} \Sigma^{0}$ reactions at the Mainz Microtron

2019 ◽  
Vol 55 (11) ◽  
Author(s):  
C. S. Akondi ◽  
K. Bantawa ◽  
D. M. Manley ◽  
S. Abt ◽  
P. Achenbach ◽  
...  
Keyword(s):  
Experimental Study ◽  
Cross Sections ◽  
Differential Cross ◽  
Legendre Polynomials ◽  
Neutral Kaon ◽  
Experimental Results ◽  
Differential Cross Sections ◽  
Theoretical Predictions ◽  
Photoproduction Reactions ◽  
Insight Into

Abstract.This work measured $ \mathrm{d}\sigma/\mathrm{d}\Omega$dσ/dΩ for neutral kaon photoproduction reactions from threshold up to a c.m. energy of 1855MeV, focussing specifically on the $ \gamma p\rightarrow K^0\Sigma^+$γp→K0Σ+, $ \gamma n\rightarrow K^0\Lambda$γn→K0Λ, and $ \gamma n\rightarrow K^0 \Sigma^0$γn→K0Σ0 reactions. Our results for $ \gamma n\rightarrow K^0 \Sigma^0$γn→K0Σ0 are the first-ever measurements for that reaction. These data will provide insight into the properties of $ N^{\ast}$N* resonances and, in particular, will lead to an improved knowledge about those states that couple only weakly to the $ \pi N$πN channel. Integrated cross sections were extracted by fitting the differential cross sections for each reaction as a series of Legendre polynomials and our results are compared with prior experimental results and theoretical predictions.

scholarly journals Numerical and experimental study of the dynamic factor of the dynamic load on the urban railway

2020 ◽  
Vol 29 (1) ◽  
pp. 195-202
Author(s):  
Tran Anh Dung ◽  
Mai Van Tham ◽  
Do Xuan Quy ◽  
Tran The Truyen ◽  
Pham Van Ky ◽  
...  
Keyword(s):  
Experimental Study ◽  
Dynamic Load ◽  
Dynamic Measurement ◽  
Experimental Results ◽  
Load Factor ◽  
Dynamic Factor ◽  
Experimental Measurements ◽  
Train Speed ◽  
Dynamic Load Factor

AbstractThis paper presents simulation calculations and experimental measurements to determine the dynamic load factor (DLF) of train on the urban railway in Vietnam. Simulation calculations are performed by SIMPACK software. Dynamic measurement experiments were conducted on Cat Linh – Ha Dong line. The simulation and experimental results provide the DLF values with the largest difference of 2.46% when the train speed varies from 0 km/h to 80 km/h

Experimental Study of a Tanker Ship Squat in Shallow Water

2014 ◽  
Vol 66 (2) ◽  
Author(s):  
Mohammadreza Fathi Kazerooni ◽  
Mohammad Saeed Seif
Keyword(s):  
Experimental Study ◽  
Shallow Water ◽  
Experimental Approach ◽  
Model Tests ◽  
Ship Hull ◽  
Experimental Results ◽  
Shallow Waters ◽  
Towing Tank ◽  
Ship Model

One of the phenomena restricting the tanker navigation in shallow waters is reduction of under keel clearance in the terms of sinkage and dynamic trim that is called squatting. According to the complexity of flow around ship hull, one of the best methods to predict the ship squat is experimental approach based on model tests in the towing tank. In this study model tests for tanker ship model had been held in the towing tank and squat of the model are measured and analyzed. Based on experimental results suitable formulae for prediction of these types of ship squat in fairways are obtained.

Experimental Study on the Optimal Thickness of Infiltration Media of the CRI System

2011 ◽  
Vol 415-417 ◽  
pp. 1703-1707
Author(s):  
Jun Min Chen ◽  
Xiao Lin Yao
Keyword(s):  
Experimental Study ◽  
Removal Efficiency ◽  
Significant Influence ◽  
Soil Column ◽  
Experimental Results ◽  
Artificial Soil ◽  
Optimal Thickness ◽  
Effluent Quality ◽  
Anaerobic Zone

Abstract. In order to investigate the optimal thickness of infiltration media in the Constructed Rapid Infiltration System, the artificial soil column is used to simulate the Constructed Rapid Infiltration System, and the CODCr, NH3-N and TN concentrations of the effluent from all the sampling sites are monitored. The experimental results and analysis show that the thickness of infiltration media exerts a significant influence on the CODCr, NH3-N and TN concentration and removal efficiency of the effluent; the CODCr, NH3-N and TN are mainly removed in the 0-1800mm zone of the artificial soil column; the total CODCr removal efficiency increases, as the thickness of infiltration media increases, but the CODCr removal efficiency in the 1800-2200mm zone is very low; the NH3-N and TN removal efficiency reaches the maximum where the thickness of infiltration media is 1800mm; the NH3-N and TN concentration of the effluent from 1800-2200mm zone dose not decrease, but increase 5-8%, due to the assimilation denitrification and amemoniation reaction on the end of the anaerobic zone; in consideration of the effluent quality, efficient biodegradation zone, construction investment, etc. the optimal thickness of infiltration media in CRI system should be 1800mm.

scholarly journals Experimental study of water droplet break up in water in oil dispersions using an apparatus that produces localized pressure drops

2019 ◽  
Vol 74 ◽  
pp. 1 ◽  
Author(s):  
Fabricio S. Silva ◽  
Ricardo A. Medronho ◽  
Luiz Fernando Barca
Keyword(s):  
Experimental Study ◽  
Droplet Size Distribution ◽  
Energy Dissipation Rate ◽  
Experimental Results ◽  
Good Prediction ◽  
Pressure Drops ◽  
Turbulence Suppression ◽  
Kolmogorov Length Scale ◽  
Control Production ◽  
Break Up

Oil production facilities have choke/control valves to control production and protect downstream equipment against over pressurization. This process is responsible for droplets break up and the formation of emulsions which are difficult to treat. An experimental study of water in oil dispersion droplets break up in localized pressure drop is presented. To accomplish that, an apparatus simulating a gate valve was constructed. Droplet Size Distribution (DSD) was measured by laser light scattering. Oil physical properties were controlled and three different break up models were compared with the experimental results. All experimental maximum diameters (dmax) were above Kolmogorov length scale. The results show that dmax decreases with increase of energy dissipation rate (ε) according to the relation dmax ∝ ε−0.42. The Hinze (1955, AIChE J.1, 3, 289–295) model failed to predict the experimental results, although, it was able to adjust reasonably well those points when the original proportional constant was changed. It was observed that increasing the dispersed phase concentration increases dmax due to turbulence suppression and/or coalescence phenomenon. Turbulent viscous break up model gave fairly good prediction.

Experimental Study of Turbulent Macroinstabilities in an Agitated System with Axial High-Speed Impeller and with Radial Baffles

1996 ◽  
Vol 61 (6) ◽  
pp. 856-867 ◽  
Author(s):  
Oldřich Brůha ◽  
Ivan Fořt ◽  
Pavel Smolka ◽  
Milan Jahoda
Keyword(s):  
Experimental Study ◽  
Flow Field ◽  
High Speed ◽  
Experimental Results ◽  
Turbulent Regime ◽  
Frequency Of Occurrence ◽  
Visualization Method ◽  
Entire Flow

The frequency of turbulent macroinstability occurrence was measured in liquids agitated in a cylindrical baffled vessel. As it has been proved by preceding experimental results of the authors, the stochastic quantity with frequency of occurrence of 10-1 to 100 s-1 is concerned. By suitable choosing the viscosity of liquids and frequency of impeller revolutins, the region of Reynolds mixing numbers was covered from the pure laminar up to fully developed turbulent regime. In addition to the equipment making it possible to record automatically the macroinstability occurrence, also the visualization method and videorecording were employed. It enabled us to describe in more detail the form of entire flow field in the agitated system and its behaviour in connection with the macroinstability occurrence. It follows from the experiments made that under turbulent regime of flow of agitated liquids the frequency of turbulent macroinstability occurrence is the same as the frequency of the primary circulation of agitated liquid.

Study of wave attenuation in concrete

1993 ◽  
Vol 8 (9) ◽  
pp. 2344-2353 ◽  
Author(s):  
J-M. Berthelot ◽  
Souda M. Ben ◽  
J.L. Robert
Keyword(s):  
Experimental Study ◽  
Plane Wave ◽  
Wave Attenuation ◽  
Plane Waves ◽  
Propagation Distance ◽  
Experimental Results ◽  
The Other ◽  
Wave Frequency ◽  
Concrete Composition ◽  
Analytical Expression

The experimental study of wave attenuation in concrete has been achieved in the case of the propagation of plane waves in concrete rods. Different mortars and concretes have been investigated. A transmitter transducer coupled to one of the ends of the concrete rod generates the propagation of a plane wave in the rod. The receiver transducer, similar to the previous one, is coupled to the other end of the rod. The experimental results lead to an analytical expression for wave attenuation as function of the concrete composition, the propagation distance, and the wave frequency.

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