THE PROBLEM

Helicopters are often used for search, rescue, and salvage jobs in remote areas. Cold temperatures in the northern areas often cause ice build-up near the engine or engine cooling bay air intake (scoop). When this happens, the engine fails. This problem has caused casualties in both Canada and the United Kingdom. The right figure shows the cross section of the cooling bay on the left from bottom up.

THE SOLUTION

The solution was to transfer engine exhaust heat to heat the intake scoop and to optimize the shape of the scoop to reduce the ice build-up and increase the engine efficiency. If the scoop is too large, it increases the air drag and it is harder to heat to the tip. If the scoop is too small, it cannot scoop enough needed air for the engine.

Two computational models were built to simulate the heat conduction and the air flow, respectively, using the Finite Element Method (FEM). OASIS found the best scoop shape design to achieve the highest engine efficiency while eliminating ice buildup.

The figure below shows the scoop designs that are the smallest, largest, and most optimal, respectively.

THE RESULTS

The optimal design successfully boosted engine performance by 7% without ice build-up. The optimal design was obtained with only 37 expensive simulations, and the design was verified to be globally optimal.