G. Oku Topal, B. Akpınar, M. F. Karabulut, N. O. Aykut, C. O. Yigit, A. A. Dindar, B. Doran, M. Bezcioglu, A. Zafer, Z. B. Cakmak
{"title":"Performance of Low-Cost GNSS in Structural Health Monitoring Studies: Shake Table Tests","authors":"G. Oku Topal, B. Akpınar, M. F. Karabulut, N. O. Aykut, C. O. Yigit, A. A. Dindar, B. Doran, M. Bezcioglu, A. Zafer, Z. B. Cakmak","doi":"10.1007/s40799-024-00710-3","DOIUrl":"10.1007/s40799-024-00710-3","url":null,"abstract":"<div><p>This contribution presents an evaluation of the effectiveness of the low-cost GNSS technique in structural health monitoring and GNSS-seismology applications. To evaluate the ability of the low-cost GNSS technique, harmonic oscillation, and earthquake tests were carried out employing the ZED-F9P-02B OEM low-cost GNSS receiver and two low-cost antennas (A10 and ANN-MB U-Blox) on a single-axis shake table. Harmonic motion experiments include frequencies ranging from 0.35 to 5.80 Hz and amplitudes between 10 and 25 mm. Moreover, the Loma-Prieta and Kobe earthquakes were simulated using a shake table to evaluate the ability of the low-cost GNSS technique to detect earthquake-induced strong ground motions. GNSS observations collected at a 20 Hz sampling interval were processed using the CSRS-PPP online service, and the ability of the low-cost GNSS technique to detect horizontal directional dynamic behaviors was validated using the relative positioning and Linear Variable Differential Transformer (LVDT) data as a reference both time and frequency domain. The max. RMSE values obtained according to the 15 harmonic oscillation test results are 2.8 mm for Geodetic Antenna Relative results, 3.3 mm for PPP, 3.2 mm for A10 Relative, 3.3 mm for PPP, 3.3 mm for UBX Antenna Relative, and 3.7 mm for PPP Results. According to the earthquake test results, the max. RMSE values obtained are 2.6 mm for Geodetic Antenna Relative results, 3.4 mm for PPP, 2.4 mm for A10 Relative, 3.8 mm for A10 PPP, 2.9 mm for UBX Antenna Relative and 4.2 mm for PPP. All results have shown that the ZED-F9P-02B GNSS receiver efficiently detects natural frequencies and structural behaviors.</p></div>","PeriodicalId":553,"journal":{"name":"Experimental Techniques","volume":"48 6","pages":"977 - 989"},"PeriodicalIF":1.5,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Novel Flexural Strain Measurement Setup for RC Beam Testing","authors":"M. Katlav, P. Turgut, K. Turk","doi":"10.1007/s40799-024-00712-1","DOIUrl":"10.1007/s40799-024-00712-1","url":null,"abstract":"<div><p>One of the most important parameters measured in the tests at laboratory–scale of reinforced concrete (RC) beams is the flexural strains required to investigate the behavior and develop a model. Flexural strains measured precisely are of great importance both in the correct interpretation of the behavior of RC beam tested and in the development of models close to the real behavior. Moment-curvature diagrams of RC beams are also created using flexural strains. The moment-curvature relationship, which is used to examine the behavior of RC beams under bending effect, is used to determine the bearing capacity of the beam and the failure modes in bending. Moment-curvature diagrams are also used to calculate the ductility of reinforced concrete beams. Therefore, it gives an idea about the amount of plastic energy that a RC beam can store. In the literature, it has been observed that there are a lot of problems encountered in the measurement of flexural strains. In this study, a flexural strain measurement setup (FSMS) is designed, manufactured, and tested on RC beam to eliminate these problems. In addition to being cost-effective and not labour intensive, FSMS developed can quickly, easily and more accurately measure the flexural strains of RC beams. It can also easily measure the flexure strains in RC beams with various cross-sectional shapes such as rectangular, triangular, trapezoidal, T, circular, etc. FSMS will certainly provide more accurate data to interpret the behavior of RC beams and to develop a model for RC beams or to check the accuracy of new strain measuring methods. As a result, the developed FSMS will provide great convenience to researchers interested in measuring flexural strains of RC beams in laboratory scale.</p></div>","PeriodicalId":553,"journal":{"name":"Experimental Techniques","volume":"48 6","pages":"965 - 976"},"PeriodicalIF":1.5,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Samadi, H. R. Goshayeshi, V. Nejati, S. R. Saleh, I. Chaer
{"title":"Computational Fluid Dynamics-Based Analysis of Magnetic Field Effect on Improvement the Performance of Stepped Solar Still","authors":"K. Samadi, H. R. Goshayeshi, V. Nejati, S. R. Saleh, I. Chaer","doi":"10.1007/s40799-024-00714-z","DOIUrl":"10.1007/s40799-024-00714-z","url":null,"abstract":"<div><p>This study focuses on improving the performance of a solar-powered desalination unit by investigating the effect of a magnetic field applied by a solenoid using a numerical solution method. The calculations in this work are based on a solar desalination device with seven steps. Since oxygen is a Paramagnetic gas the moist airflow in this solar desalination could be checked by applying an external magnetic field through a solenoid. The governing equations for the problem have been discretized using the finite volume method. The effects of the applied magnetic field generated by the solenoid are investigated in terms of flow streamlines, contour plots of velocity, and pressure, both in ignoring and considering the influence of magnetic field intensity. Three different combinations of NI (N is the number of solenoid turns, and I is the electric current intensity) are examined with values of 2.5 × 10<sup>4</sup>, 2.5 × 10<sup>5</sup>, and 10 × 10<sup>5</sup>. For the applied magnetic field with NI = 10 × 10<sup>5</sup>, it has been observed that the evaporation rate reaches its maximum value in all stages of the solar desalination water slide, resulting in an increased water evaporation rate in the solar desalination device. The evaporation rate has approximately reached the maximum value of 1.02 × 10<sup>−1</sup> (kg/s) in all parts of the solar desalination device.</p></div>","PeriodicalId":553,"journal":{"name":"Experimental Techniques","volume":"48 6","pages":"991 - 1003"},"PeriodicalIF":1.5,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On the Cover: Nine Point Bending Test Technique for Understanding of Sintered Silver Die Bonding Failure Mechanism","authors":"","doi":"10.1007/s40799-024-00711-2","DOIUrl":"10.1007/s40799-024-00711-2","url":null,"abstract":"","PeriodicalId":553,"journal":{"name":"Experimental Techniques","volume":"48 3","pages":"393 - 393"},"PeriodicalIF":1.5,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140799992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Study on Velocity Distribution on Cross-Section Flow of T-Shunt","authors":"L. Fang, Q. Gao, C. Zhou, B. Han, B. Ge","doi":"10.1007/s40799-024-00709-w","DOIUrl":"10.1007/s40799-024-00709-w","url":null,"abstract":"<div><p>T-shunt is one of the commonly used components in gas-liquid two-phase flow pipeline. It has the function of separating, transmitting and carrying fluid. The junction of the T-shunt is the area of diversion and confluence in the pipeline. In this paper, we study the characteristics of the T-shunt in the cross-section of the fluid flow. A visual window is installed at the end of the experimental T-shunt section, and the fluorescence pipe’s cross-section image captured through the visual window is illuminated by the laser above the pipe. The fluid velocity field is calculated using the PIV (Particle Image Velocimetry) method and the velocity field is classified and analyzed. The result shows that there are great differences in fluid flow patterns on the cross-sections of the T-shunt at different positions, and great differences in the fluid erosion and corrosion of the pipe wall at different positions away from the T-shunt outlet.</p></div>","PeriodicalId":553,"journal":{"name":"Experimental Techniques","volume":"48 6","pages":"953 - 963"},"PeriodicalIF":1.5,"publicationDate":"2024-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140671175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Path-Integrated X-Ray Digital Image Correlation using Synthetic Reference Images","authors":"S. S. Fayad, E.M.C. Jones, C. Winters","doi":"10.1007/s40799-024-00707-y","DOIUrl":"10.1007/s40799-024-00707-y","url":null,"abstract":"<div><p>X-rays can provide images when an object is visibly obstructed, allowing for motion measurements via x-ray digital image correlation (DIC). However, x-ray images are path-integrated and contain data for all objects between the source and detector. If multiple objects are present in the x-ray path, conventional DIC algorithms may fail to correlate the x-ray images. A new DIC algorithm called path-integrated (PI)-DIC addresses this issue by reformulating the matching criterion for DIC to account for multiple, independently-moving objects. PI-DIC requires a set of reference x-ray images of each independent object. However, due to experimental constraints, such reference images might not be obtainable from the experiment. This work focuses on the reliability of synthetically-generated reference images, in such cases. A simplified exemplar is used for demonstration purposes, consisting of two aluminum plates with tantalum x-ray DIC patterns undergoing independent rigid translations. Synthetic reference images based on the “as-designed” DIC patterns were generated. However, PI-DIC with the synthetic images suffered some biases due to manufacturing defects of the patterns. A systematic study of seven identified defect types found that an incorrect feature diameter was the most influential defect. Synthetic images were re-generated with the corrected feature diameter, and PI-DIC errors were improved by a factor of 3-4. Final biases ranged from 0.00-0.04 px, and standard uncertainties ranged from 0.06-0.11 px. In conclusion, PI-DIC accurately measured the independent displacement of two plates from a single series of path-integrated x-ray images using synthetically-generated reference images, and the methods and conclusions derived here can be extended to more generalized cases involving stereo PI-DIC for arbitrary specimen geometry and motion. This work thus extends the application space of x-ray imaging for full-field DIC measurements of multiple surfaces or objects in extreme environments where optical DIC is not possible.</p></div>","PeriodicalId":553,"journal":{"name":"Experimental Techniques","volume":"48 6","pages":"941 - 951"},"PeriodicalIF":1.5,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40799-024-00707-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140595294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Optimizing Metrological Efficiency: Comparative Analysis of Filtering Methods for 2D DIC","authors":"T. Fourest","doi":"10.1007/s40799-024-00708-x","DOIUrl":"10.1007/s40799-024-00708-x","url":null,"abstract":"<div><p>Digital Images Correlation (DIC) measures are widely used in order to calibrate models. It is very common for researchers to use filters on these measurements to improve the measurement resolution (decrease the noise level) before using them with various methodologies. However, the effects of these filters on the tradeoff between spatial resolution and measurement resolution are not fully understood. The objective of the study is to compare seven common denoising/filtering methods for 2D DIC with affine subset shape function, including image filters (Gaussian, Median), frequency filters (Lowpass Butterworth, Holoborodko), local polynomial fitting (Savitzky-Golay filter, cubic splines), and Finite Elements mapping. The proposed methodology to compare the enhancement of these methods is based on the star pattern test cases used in the DIC Challenge 2.0. Hence, this study aims to obtain a general comparison of the filtering methods as opposed to case-dependent approaches. To that end, firstly, the FOLKI-D DIC code is metrologically qualified using the DIC Challenge 2.0 methodology and test cases. Then, the filtering methods are applied to the displacements and strain maps computed with the FOLKI-D code for various DIC subset sizes and filter parameters. It is found that displacement and strain map enhancements vary significantly depending on the filter. Some methods show no improvement (or worsened tradeoff in the strain case), while others achieve similar resolution tradeoffs as DIC codes using quadratic subset shape functions. Finally, it is concluded that the filter choice significantly impacts results, with higher-order lowpass Butterworth, Savitzky-Golay, and Finite Elements mapping methods showing preference over others studied.</p></div>","PeriodicalId":553,"journal":{"name":"Experimental Techniques","volume":"48 5","pages":"921 - 934"},"PeriodicalIF":1.5,"publicationDate":"2024-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140595300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Damage Evolution Model Considering Fatigue Failure Factor Under Multiaxial Non-Proportional Loading","authors":"Z. Ren, X. Qin, Q. Zhang, Y. Sun","doi":"10.1007/s40799-024-00706-z","DOIUrl":"10.1007/s40799-024-00706-z","url":null,"abstract":"<div><p>The Chaudonneret model cannot fully and effectively characterize the linear correlation between the strain energy density release rate and the number of cycles in the damage evolution stage of low carbon alloy steels under multiaxial non-proportional loading. In order to solve this problem, the fatigue failure process of Q355B is captured by digital image correlation technology, and the factors affecting fatigue failure under multiaxial loading are analyzed in combination with fracture morphology characteristics. Based on the concept of critical plane, a new stress combination form is introduced to reflect the failure factors, and the corresponding damage evolution model is proposed. The model considers the interaction between different stresses and can describe the damage evolution law under non-proportional loading. Compared with different types of life prediction models, the distribution range of life prediction results of the improved model under multiaxial non-proportional loading has a good correlation with the experimental values.</p></div>","PeriodicalId":553,"journal":{"name":"Experimental Techniques","volume":"48 5","pages":"905 - 920"},"PeriodicalIF":1.5,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140595303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On the Cover: High‑Order Time‑Domain DIC Algorithm Based on a Nonlinear Optical Flow Equation","authors":"","doi":"10.1007/s40799-024-00705-0","DOIUrl":"10.1007/s40799-024-00705-0","url":null,"abstract":"","PeriodicalId":553,"journal":{"name":"Experimental Techniques","volume":"48 2","pages":"189 - 189"},"PeriodicalIF":1.5,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140033225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An Experimental Study on the Dependency of Thermal Resistance of Additively Manufactured Micro-Channel Heat Sinks on Channel Cross-Sections","authors":"A.N. Kivanani, S. Khalilpourazary, F. Mobadersani","doi":"10.1007/s40799-024-00703-2","DOIUrl":"10.1007/s40799-024-00703-2","url":null,"abstract":"<div><p>Cooling by micro-channel heat sink transfers excess heat flux in electrical devices and increases their functional capacity, reliability, and life span. In this paper, AlSi10Mg powders were employed to create four micro-channel heat sinks with cross-sections including square, rectangle, circle, and ellipse with an additive manufacturing method. To investigate the impact of micro-channel heat sink cross-sectional geometry on thermal resistance, Taguchi’s L25 orthogonal array was utilized. Reynolds number and electric power were selected to be the input parameters. The experimental tests were conducted using an experimental setup and distilled water as the working fluid in the laminar flow regime. The results obtained from the experimental tests indicated that in the range of electric power from 4 to 12 W and Reynolds numbers of 50, 100, 150, 200, and 250, the micro-channel heat sink with a square cross-section exhibits the highest heat transfer performance. Finally, an analysis of variance was conducted to study the impact of the Reynolds number and electric power factors on thermal resistance. The findings revealed the significant effect of electric power on thermal resistance in micro-channel heat sinks compared to the Reynolds number in the laminar regime. Additionally, a comparison was made with other available results.</p></div>","PeriodicalId":553,"journal":{"name":"Experimental Techniques","volume":"48 5","pages":"877 - 891"},"PeriodicalIF":1.5,"publicationDate":"2024-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139917726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}