An inlet guide assembly for a turbine receiving a pulsed flow, including a duct having an internal volume, and an inlet port, first outlet nozzle and second outlet nozzle each communicating with the internal volume. The inlet port is configured to receive at least part of the pulsed flow. The first and second outlet nozzles each define a respective nozzle area communicating between the internal volume and a flow path of the turbine. The first and second outlet nozzles are spaced from one another with the first outlet nozzle located closer to the inlet port than the second outlet nozzle relative to a flow direction through the duct, the nozzle area of the first outlet nozzle being smaller than the nozzle area of the second outlet nozzle. A compound engine assembly and method of introducing a pulsed flow into a flow path of a turbine are also discussed.