Oxygen pressure relief and ventilation system and method
An oxygen pressure relief and ventilation system includes a flow fuse fluidly coupled downstream of a pressure regulator. The pressure regulator is operatively coupled to an oxygen tank, and the oxygen tank is located in an unpressurized compartment of an aircraft. A pressure relief valve is fluidly coupled downstream of the flow fuse. A ventilation pathway fluidly couples the unpressurized compartment with a pressurized compartment. The flow fuse and the pressure relief valve are configured to cooperatively mitigate downstream flow of pressurized oxygen if the pressure regulator fails. The ventilation pathway is configured to allow air from the pressurized compartment to pass through to the unpressurized compartment for diluting a concentrated oxygen in the unpressurized compartment.
1. An oxygen pressure relief and ventilation system, comprising:
a flow fuse fluidly coupled downstream of a pressure regulator, wherein the pressure regulator is operatively coupled to an oxygen tank, and the oxygen tank is located in an unpressurized compartment of an aircraft;
a pressure relief valve fluidly coupled downstream of the flow fuse; and
a ventilation pathway fluidly coupling the unpressurized compartment with a pressurized compartment,
wherein the flow fuse and the pressure relief valve are configured to cooperatively mitigate downstream flow of pressurized oxygen if the pressure regulator fails, and
wherein the ventilation pathway is configured to allow air from the pressurized compartment to pass through to the unpressurized compartment for diluting a concentrated oxygen in the unpressurized compartment.
2. The system of claim 1 , wherein the flow fuse comprises a pneumatically-actuated valve.
3. The system of claim 1 , wherein the flow fuse comprises a spring-loaded mechanism that biases the flow fuse into a first position that allows flow of oxygen to pass.
4. The system of claim 3 , wherein the spring-loaded mechanism is configured such that when the pressure of oxygen surpasses a predetermined pressure, a force of the spring-loaded mechanism is overcome thereby pushing the flow fuse to a second position that substantially blocks flow of oxygen for protecting downstream components.
5. The system of claim 4 , wherein the flow fuse automatically resets back to the first position when the pressure of oxygen from upstream is restored to below the predetermined pressure.
6. The system of claim 4 , wherein the second position is configured to allow some pressurized oxygen to pass for limiting an upstream pressure while also protecting downstream components.
7. The system of claim 6 , wherein the pressure relief valve is located in the unpressurized compartment and configured to vent pressurized oxygen that has passed the flow fuse into the unpressurized compartment.
8. The system of claim 7 , wherein the pressure relief valve is configured to vent pressurized oxygen upon exposure of the pressure relief valve to a predetermined pressure.
9. The system of claim 1 , wherein the ventilation pathway comprises a tube configured to allow a fixed flow rate of air from the pressurized compartment to pass through a barrier to the unpressurized compartment.
10. The system of claim 9 , wherein the ventilation pathway comprises an inlet having a flow-limiting device that is opened by a predetermined amount of pressure to allow air to flow through the tube.
11. The system of claim 9 , wherein the tube comprises an outlet having a throat configured to allow a predetermined amount of air through the tube.
12. The system of claim 9 , wherein the tube comprises a muffler configured for reducing noise produced by the ventilation pathway.