Development of a venting valve for nursing bottles

This project aims to develop an innovative venting technique for nursing bottles with natural flow. Conventional nursing bottles are completely sealed except for the small hole on the teat. Without appropriate venting, the partial vacuum (i.e., negative pressure) inside the bottle results in gastrointestinal disorders in infants such as colic and secretory otitis. In addition, intraoral negative pressure transmitted to middle ear causes secretory otitis with a risk for delayed speech development. This study presents the design, modeling and fabrication process of new venting system for the nursing bottle based on an innovative flexible valve. Liquid silicon rubber was used to fabricate the valve, which was able to respond to the pressure difference between the inside and outside of the bottle. It not only closes the air entrance when the bottle stands on its base but also opens the air path while the infant sucks the milk. The specific geometry of the valve adjusts the response based on the pressure difference. The static structural response of the valve to both positive and negative pressures was simulated with finite element analysis. Moreover, the fluid-structural interaction analysis was carried out to show the transient response of both fluid flow and flexible structure to the pressure difference. In order to optimize the design, valves with different thicknesses and curvatures were tested. An experimental set-up was built using a nursing bottle equipped with pressure sensors and a vacuum pump to test the actual infant’s sucking condition. Five valves with different geometries were fabricated for the experiments. The experimental results were validated by the simulation results. Criterion parameters of the system, such as intake volume of milk, minimum pressure, working pressure, and temporal characteristics of the valves were statistically analyzed. Finally, the optimization based on the statistical results provided the most reliable design that can deliver the more comfortable feeding condition.Applied Science, Faculty ofEngineering, School of (Okanagan)Graduat