Digital Image Analysis to Determine Pore Opening Size Distribution of Nonwoven Geotextiles

Abstract

The filtration performance of a geotextile is controlled by its pore opening size distribution ͑PSD͒. Current methods for determining PSD are mostly indirect and contain inherent disadvantages. Recent technological advancements in image analysis offer great potential for a more accurate and direct way of determining the PSD of nonwoven geotextiles. A new and accurate method of image analysis for PSD determination of nonwoven geotextiles is presented in this paper. The image analysis method was developed using various mathematical morphology algorithms to provide a complete PSD curve for each geotextile. The two characteristic pore opening sizes, O 95 and O 50 , were determined from image analysis and were compared to the results from laboratory tests, analytical equations, as well as manufacturer's reported apparent opening sizes ͑AOS͒. The image-based O 95 pore opening size of various geotextiles was comparable to the manufacturer's reported AOS as well as to those determined from the laboratory dry sieving test. However, the measured O 50 pore opening size was lower than the one determined using the analytical equations developed by two previous researchers. Overall, the image analysis method presented provides a unique and accurate method that can measure fiber thickness and pore opening sizes in a cross-sectional image of a woven geotextile.

Distance transform algorithm for measuring nanofiber diameter

“…In the last few years, image analysis methods have been developed in order to identify fibers and measure nonwoven characteristics such as fiber orientation [9][10][11][12][13][14][15][16], fiber diameter [17,18], pore size [19], [20], uniformity [21] and other structural features [15,22]. However, since these are new techniques and their accuracy and limitations have not been verified, samples with known characteristics are required to evaluate the accuracy of the methods which can be produced by simulation schemes [9,23].…”

Simulated image of electrospun nonwoven web of PVA and corresponding nanofiber diameter distribution

“…Consequently, accurate and automated measurement of fiber diameter is useful and crucial. Recently, image analysis techniques have been used to evaluate nonwoven structures [8][9][10][11][12][13][14][15][16][17]. The objective of our research is to develop an image analysis based method to serve as a simple and efficient alternative for electrospun fiber diameter measurement.…”

“…It is well known that the distribution of structural characteristics such as fiber orientation [8][9][10][11][12][13], fiber diameter [14,15], pore size [16], uniformity [17] and other structural characteristics [15] are very important when determining the properties of nonwoven textiles. The properties of electrospun nonwoven webs are determined by the above-mentioned features as well.…”

Nano Fiber Images Thresholding based on Imperial Competitive Algorithm

“…In another investigation [24] to measure the diameter, threshold value was selected for Nano fiber images on the base of trial and error method. Pore size is another important property of Nano fiber web which has been used by [25][26][27], to measure pores with image processing.…”