Determining the volume of a tube cross section plays a crucial role in the analysis of samples. To calculate this volume, the shell method is employed, following the equation:

Where R represents the measurement from the center of the tube (excluding the center of the wall). To begin the volume calculation, start by uploading an image of the sample onto the website. Then, utilize the dot tool to define the desired calculation area and outline it accordingly. This designated area will be divided into a finite number of nodes. The size of each node is determined based on a reference scale line that you provide, which can be established using either a known length or a scale measurement. Subsequently, the volume of each node is determined by evaluating the horizontal distance relative to the center of the tube wall. This involves placing a vertical reference line and indicating the distance between the line and the center of the tube, typically on the inner wall. By clicking the "calculate" button, you can obtain the precise volume measurement for your analysis.