Results of an Experimental Research of a Solar Concentrating Module With Louvered Heliostats

2021 ◽  
pp. 104-126
Keyword(s):  
Experimental Data ◽  
Information Processing ◽  
Solar Radiation ◽  
Computer Program ◽  
Relative Error ◽  
Experimental Research ◽  
Automatic Measurement ◽  
Parabolic Cylinder ◽  
Mirror Surface ◽  
Solar Concentrator

The developed system of automatic measurement of the main parameters of a solar concentrating module with PV, PVT, and heat receivers allows you to save time during information processing, to obtain data on the dynamics of the processes in the solar concentrating module with the required measurement periodicity. The developed algorithm for calculating the passage of sunlight through the mirror surface of the lamellae and the parabolic cylinder, implemented as a computer program, allows calculating the flow of solar radiation on the receiving surface of the solar concentrator with a relative error of not more than 5%, which is confirmed by experimental data.

Theoretical Bases of the Use of Solar Concentrating Modules With Louvered Heliostats

2021 ◽  
pp. 44-73
Keyword(s):  
Solar Radiation ◽  
Concentration Ratio ◽  
Functional Relationship ◽  
Three Dimensional ◽  
Parabolic Cylinder ◽  
The Sun ◽  
Mirror Surface ◽  
Solar Concentrator ◽  
Dimensional Problem ◽  
Angular Aperture

A functional relationship was obtained linking the position of the Sun, the step of the mirror lamellae of the heliostat, and their orientation to ensure zero blocking and shading losses in the louvered heliostat. Based on the consideration of a three-dimensional problem, the algorithm for calculating the passage of sunlight through the mirror surface of the lamellae and parabolic cylinder allows calculating the flux of solar radiation on the receiving surface of the solar concentrator. An algorithm for controlling lamellar heliostat mirror lamellas has been developed that significantly increases the efficiency of a solar concentrator—using a louvre heliostat with a constant lamella pitch is equivalent to increasing the angular aperture of the concentrator from 26° to 70° without reducing the concentration ratio.

Energy Balances on a Parabolic Cylinder Solar Collector

1962 ◽  
Vol 84 (1) ◽  
pp. 24-32 ◽  
Author(s):  
G. O. G. Lof ◽  
D. A. Fester ◽  
J. A. Duffie
Keyword(s):  
Experimental Data ◽  
Solar Radiation ◽  
Solar Collector ◽  
Concentration Ratio ◽  
Meteorological Variables ◽  
Parabolic Cylinder ◽  
Solar Collectors ◽  
Cylindrical Reflector ◽  
Energy Balances ◽  
Focal Zone

A technique for optimizing the design of focusing solar collectors was developed through a detailed study of the energy balances for a parabolic-cylindrical reflector with tubular receivers of three diameters. Experimental data for concentration ratios of 10 to 22.5 and surface temperatures of 88 to 353 deg F are presented. Receiver temperature, meteorological variables (including solar radiation), and distribution of reflected radiation in the focal zone of the reflector were measured and correlated so as to permit optimization of concentration ratio.

Three-Dimensional Analysis of a Concentrated Solar Flux

2008 ◽  
Vol 130 (1) ◽  
Author(s):  
David Riveros-Rosas ◽  
Marcelino Sánchez-González ◽  
Claudio A. Estrada
Keyword(s):  
Thermal Stress ◽  
Solar Radiation ◽  
Computer Program ◽  
Ray Tracing ◽  
Solar Irradiance ◽  
Radiation Flux ◽  
Three Dimensional ◽  
Mirror Surface ◽  
Concentrated Solar Radiation ◽  
Focal Zone

In order to improve the durability of receivers used in solar concentrating systems, it is necessary to minimize thermal stress during their operation. A possible way to do that is to design receivers in which the radiative flux density is homogeneous at the surface. For this reason, a detailed 3D study has been carried out for the distribution of concentrated solar radiation in the focal zone of a parabolic concentrator. A computer program has been developed to obtain isosurfaces of solar irradiance and achieve a homogeneous radiation flux on the receiver surface. The algorithm of the program proposes a methodology to obtain flux isosurfaces for a great variety of optical configurations. The effect of the optical errors on the mirror surface has been studied, as well as the effect of the shape of the mirror, e.g., round, square, or faceted. The numerical calculations were made using the convolution ray tracing technique.

AN EXPERIMENTAL RESEARCH OF A SPILLWAY WITH A WIDE THRESHOLD OF A RESERVE WATER OUTLET

2015 ◽  
Vol 5 (3) ◽  
pp. 73-81
Author(s):  
Yuriy Mikhaylovich KOSICHENKO ◽  
Evgeniy Dmitrievich MIKHAYLOV ◽  
Oleg Andreevich BAEV
Keyword(s):  
Experimental Data ◽  
Relative Error ◽  
Experimental Research ◽  
Structural Engineering ◽  
Discharge Coefficient ◽  
Experimental Studies ◽  
Experimental Results ◽  
Empirical Dependence ◽  
Microsoft Excel ◽  
Water Leakage

The aim of this paper is to introduce results of an experimental research of a spillway with a wide threshold. To identify this spillway main characteristics the authors use traditional methods of hydraulic calculations. The paper presents experimental data of a spillway with a wide threshold at δ/H>8...10 which were obtained on a hydraulic tray in the laboratory of hydro technical structures and structural engineering of Don State Agrarian University named after A.K. Kortunov. The research demonstrates basic dependences for the event of water leakage through a spillway with a wide threshold for a fl at stress problem. The obtained values of discharge coefficient for a spillway with a wide threshold at δ/H>8...10 are within the limits of 0,303≤mспр≤0,305 with a relative error 0.0242-0.0076%. Taking in account experimental studies and using a well-known formula by H.А. Tibara the authors specified the dependence for calculating discharge coefficient for a spillway with a wide threshold. The experimental results were mathematically processed by Microsoft Excel, and a new empirical dependence m=f(P/H) was introduced.

EXPERIMENTAL STUDY OF THE KINEMATIC PARAMETERS OF MOVEMENT OF CARS FORCED IDLE MOTION

2018 ◽  
pp. 52-57
Author(s):  
Ivelin Kostov
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Experimental Research ◽  
Kinematic Parameters ◽  
Research Results ◽  
Software Product

In the work brought some experimental data of kinematic parameters of movement of cars forced idle, as the software product was used to diagnose 900 ATS, which recorded kinematic parameters of vehicle. On the basis of the conducted experimental research results are shown tabulated and analysed.

The Stress Analysis and Experimental Research of Tubular K-Joints With Overlap

1987 ◽  
Vol 109 (4) ◽  
pp. 375-380
Author(s):  
Tie-yun Chen ◽  
Wei-min Chen
Keyword(s):  
Experimental Data ◽  
Stress Concentration ◽  
Variational Method ◽  
Stress Analysis ◽  
Experimental Research ◽  
Hot Spot ◽  
Intersection Point ◽  
Tubular Joints ◽  
Photoelastic Experiment ◽  
Intersection Curves

The geometry of overlapping tubular joints, the equations of intersection curves and the coordinate of the intersection point are introduced first. The variational method for simple tubular joints is extended to the stress analysis of tubular K-joints with overlap. The computer program is compiled. The stress concentration factor and the position of the hot spot of an overlapping joint are found. For the sake of proving the feasibility of our analysis and program, the computed results are compared with experimental data of our photoelastic experiment and other experiments.

Experimental and Theoretical Investigation of Performance of a Solar Chimney Model, Part I: Experimental Investigation

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Essaied M Shuia ◽  
Bashir H Arebi ◽  
Ibrahim A abuashe
Keyword(s):  
Experimental Data ◽  
Wind Speed ◽  
Solar Radiation ◽  
Air Temperature ◽  
Solar Collector ◽  
Experimental Results ◽  
Internal Diameter ◽  
Solar Chimney ◽  
Air Velocity ◽  
Collector Temperature

This paper presents the experimental data that was collected from small pilot solar chimney. The experimental data together with ambient conditions are used to evaluate the performance and study the behavior of the solar chimney; this data will be used for comparison with theoretical models in another paper [part II). The solar chimney prototype was designed and constructed at the Subrata Faculty of Engineering-Libya. The data were collected over several days of June 2011. The solar chimney system contains two main components; the solar collector and the solar chimney. The solar collector root‘ has a circular area of126 m3, the solar chimney is a PVC tube with internal diameter of 0.2 m and the total height of chimney is 9.3 m. The measurements include the intensity of solar radiation inside/outside the collector, temperature and velocity of air at the entrance of the chimney, temperature and speed of wind outside the collector, temperature of the ground inside collector al1d temperature measurements of air at speci?c points at different levels throughout the collector. Solar irradiance was found to affect the chimney temperature and subsequently affects chimney air velocity. The experimental results showed that temperature differences of (30 - 45°C) were recorded between the ambient temperature and that of air inside the chimney in the middle of the day, where the highest air temperature of 73.4°C was recorded at the entrance of the solar chimney. The maximum air velocity of 3.6 m/s was recorded inside the solar chimney at noon on 9 June. Wind speed outside the collector had a small effect on the speed of the air inside the chimney and tends to change slightly, hence, can neglect influence of wind speed on the performance of the system. Also the experimental results indicate that such type of system can trap a suf?cient amount of solar radiation, which elevates the air temperature to a suf?cient value able to generate enough air ?ow to operate a wind turbine to produce electricity; this means the solar chimney system for electricity production can work in the north-western part of Libya in the summer time at least.

Impact Simulation of a Crashworthy Composite Fuselage Section with Energy-Absorbing Floor

2014 ◽  
Vol 529 ◽  
pp. 102-107
Author(s):  
Hai Bo Luo ◽  
Ying Yan ◽  
Xiang Ji Meng ◽  
Tao Tao Zhang ◽  
Zu Dian Liang
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Dynamic Response ◽  
Relative Error ◽  
High Strength ◽  
Computer Code ◽  
Impact Simulation ◽  
Average Acceleration ◽  
Simulation Results ◽  
Energy Absorbing

A 7.8m/s vertical drop simulate of a full composite fuselage section was conducted with energy-absorbing floor to evaluate the crashworthiness features of the fuselage section and to predict its dynamic response to dummies in future. The 1.52m diameter fuselage section consists of a high strength upper fuselage frame, one stiff structural floor and an energy-absorbing subfloor constructed of Rohacell foam blocks. The experimental data from literature [6] were analyzed and correlated with predictions from an impact simulation developed using the nonlinear explicit transient dynamic computer code MSC.Dytran. The simulated average acceleration did not exceed 13g, by contrast with experimental results, whose relative error is less than 11%. The numerical simulation results agree with experiments well.

scholarly journals Necessary auxiliary background for efficient use of an existing computer program of non-parametric fitting of nonlinear equations

2009 ◽  
Vol 52 (2) ◽  
pp. 437-448 ◽  
Author(s):  
Emmanuel M. Papamichael ◽  
Leonidas G. Theodorou
Keyword(s):  
Experimental Data ◽  
Computer Program ◽  
Nonlinear Equations ◽  
Significant Contribution ◽  
Chemical Processes ◽  
Programming Support ◽  
Parametric Fitting ◽  
Non Parametric

This work constituted a significant contribution for more efficient use of a valuable computer program of non-parametric fitting of nonlinear multiparametric equations to experimental data. However, prerequisite in this context was the transformation of nonlinear multiparametric equations into linear hyperplane forms before their incorporation within the computer program; this latter was decisive and a matter of proper programming practice. Herein, a series of widely used equations useful in different fields of chemical processes, in biochemistry and/or in biotechnology, along with their suitable transformations as well as the appropriate programming support are being reported.

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