Comparison of test methods for measuring the net buoyant force of buoyant materials

Abstract

Purpose: Net buoyant force is a crucial factor affecting the functional performance of clothing for water safety. This study aims to develop an alternative method for measuring the net buoyant force of various buoyant materials such as buoyant fabrics, on a small scale in a more accurate and efficient way than the existing method. Design/methodology/approach: The net buoyant forces of buoyant materials with different thicknesses and forms were determined and compared using three methods. In Method 1, the traditional method involving mathematical calculations was used; Method 2 involved using the buoyancy-measuring device from the study of Jin et al. (2018) and Method 3 involved using an alternative buoyancy-measuring system that simulates the actual situation of using buoyant swimwear by measuring the force needed to submerge the buoyant material in water at a standard depth. The net buoyant forces of 22 buoyant materials were measured and compared to test these three methods. The accuracy, reproducibility, sensitivity and validity of these methods were then statistically compared. Findings: The results obtained with the alternative buoyancy-measuring system had higher accuracy, reproducibility and validity than the results obtained through mathematical calculations. The sensitivity of the buoyancy-measuring system (Methods 2 and 3) was higher than that of the traditional method involving calculations (Method 1). Originality/value: An alternative method is proposed to measure the net buoyant force of buoyant materials on a small scale with higher accuracy, reproducibility and sensitivity.