TECHNICAL FIELD

The application relates generally to the cooling and lubrication of gas turbine engines and, more particularly, to a shared oil system for an engine component and a generator driven by the engine.

BACKGROUND OF THE ART

Gas turbine engines may drive generators for generating electrical power for aircraft use. These generators are generally air or oil cooled. For oil cooled generators, it can be preferential to integrate an oil system for the generator with an oil system for an engine component of the engine into a shared engine oil system. In the shared engine oil system, oil return lines from the generator and the engine component return the oil into the engine oil system. However, this arrangement may expose the engine oil system to contamination from the generator.

In some instances, large quantities of contaminant may be liberated from the generator and may damage the engine component. The contamination may also block a strainer installed in the oil return lines.

SUMMARY

In one aspect, there is provided a method of distributing oil within a gas turbine engine, the method comprising directing a first oil flow from an oil source to an engine component of the gas turbine engine and back to the oil source; directing a second oil flow from the oil source to a generator driven by the gas turbine engine and back to the oil source; monitoring a parameter of the second oil flow downstream of the generator and upstream of the oil source; detecting a contaminant in the second oil flow based on the parameter; and reducing the second oil flow to the generator without reducing the first oil flow to the engine component when the contaminant is detected.

In another aspect, there is provided a shared oil system for a component of a gas turbine engine and a generator driven by the gas turbine engine, the oil system comprising an oil source; a first oil circulation path defining a fluid communication from the oil source to the engine component and back to the oil source; a second oil circulation path defining a fluid communication from the oil source to the generator and back to the oil source, the first and second oil circulation paths being defined at least in part in parallel from the oil source to the engine component and from the oil source to the generator; at least one pump in fluid flow communication with the first and second oil circulation paths; a detector disposed in the second oil circulation path downstream of the generator and upstream of the oil source for measuring at least one parameter indicative of a contaminant in an oil flow exiting the generator; a valve disposed in the second oil circulation path upstream of the generator between the generator and the oil source, the valve operably connected to the detector and configured to be actuable upon detection of the contaminant by the detector.

In a further aspect, there is provided a shared oil system for a component of a gas turbine engine and a generator driven by the gas turbine engine, the oil system comprising an oil source; a first oil circulation path providing fluid communication between the engine component and the oil source; a second oil circulation path providing fluid communication between the generator and the oil source at least in part independently from the first oil circulation path; at least one pump in fluid communication with the first and second oil circulation paths; a detector configured to measure at least one parameter indicative of a contaminant in an oil flow in the second oil circulation path downstream of the generator and upstream of the oil source and to send a value indicative of the measurement; a valve disposed in the second oil circulation path upstream of the generator and downstream of the oil source, the valve being actuable by a command signal; and a control system operatively connected to the detector and the valve, the control system configured to compare the value indicative of the measurement with a corresponding threshold and to send the command signal to the valve when the value exceeds the corresponding threshold.

