Experimental optimization and multivariate analysis of explosive-driven water projection devices for IED neutralization: A response surface methodology study

The increasing risk of terrorist attack by Improvised Explosive Device (IED) has led security forces to seek effective means for their safe deactivation. High-velocity water projection has proven useful for this purpose. However, there is a lack of knowledge about the design parameters and the complex multivariate relationship between the factors that affect optimal water propagation. To support the development of a novel counter-IED device, based on omnidirectional explosive-driven water projection, an experimental and statistical approach, based on Response Surface Methodology (RSM), is proposed that allows, for the first time, to analyze the curvature of the multivariate response surface for this phenomenon. The design is based on a simple concept, which can be manufactured easily and cheaply by additive manufacturing (3D printing), in a repetitive and reliable manner. Through an experimental matrix of 40 tests, the detonation-driven water propagation velocity is measured by high-speed camera velocimetry. The analysis identified explosive mass per unit length as the primary factor driving water-front velocity, with higher loading consistently producing greater velocities. Device diameter exhibited an inverse effect, reducing velocity as size increased. The explosive–diameter interaction was significant: velocity gains plateau for small diameters beyond ∼40 g/m, but continue rising for larger diameters (e.g., 120 mm). Thicker tubes inner tubes improved performance in larger devices but hindered it in smaller ones. ANOVA confirmed the model’s robustness, showing no lack of fit, normal residuals, and statistical significance for diameter (P = 0.000), explosive amount (P = 0.000), and the interactions diameter–explosive (P = 0.017) and diameter–inner-tube thickness (P = 0.038). Finally, a regression equation is found which provides information on the velocity of the projected water, based on the design parameters, which contributes to the goal of achieving an efficient and safe design.