Design of Nitrous Oxide-Referencing Fuel Pressure Regulator

Abstract

Nitrous oxide can be used for internal combustion engines as a supplemental oxidizer. In a nitrous oxide system the nitrous is stored in a pressurized container or bottle. Under dynamic use, as the nitrous oxide is being spent the mass in the bottle decreases. This decrease in mass leads to a decrease in pressure. The pressure is the source of delivery of the nitrous oxide to the system. Typically nitrous oxide systems do not have a way to maintain a constant oxidizer deliver flow that can adjust to the pressure drop in the bottle as the nitrous oxide is spent. By not having a way to maintain the oxidizer deliver as the bottle pressure drops it becomes hard to stay consistent interms of the Air (Oxidizer) to Fuel ratio (A/F). The net effect of this pressure drop is that the A/F changes. When this happens the performance of the engine may be compromised as well as the health of the engine. One way to maintain the A/F by regulating the pressure the fuel pressure with respect to the nitrous oxide bottle pressure. This regulator is the focus of this project. A pressure regulator would insure that a constant pressure after the regulator could be maintained. The theory behind the regulator has been previously established but the want of a design of a regulator for a certain application has been brought to the design teams attention. A dynamometer test lab based in Milwaukee has offered testing support for the design of a pressure regulator that would maintain a constant A/F mixture delivery. Motorcycles, due to the need for small components, need to have small nitrous oxide bottles when they are set up with nitrous oxide systems. This small bottle empties faster than a large bottle so the need to maintain the A/F is even more applicable for use on a motorcycle.