Product design and development

A: A would still happen because blocked minimum flow converts hydraulic power to heat locally. B remains a risk since NPSH is independent of recycle position once suction conditions degrade. C is a common left-of-curve effect that the recycle is meant to avoid but cannot if it's failed. D doesn't apply because the recycle valve doesn't limit discharge pressure; the pump curve and relief devices do.

A: A would unnecessarily recycle and cut throughput because colder inlet air actually improves margin. C misreads the map since colder gas raises mass flow for the same volumetric rate, not lowers it. D reverses density effects and would over-speed the machine. B aligns with compressor maps where lower inlet temperature increases head and shifts operation away from surge.

A: A underestimates by dropping pressure work entirely. B is the raw hydraulic power (2 × 5 = 10 kW) but ignores efficiency. D is off by two orders because duty cycle doesn’t multiply power. C follows the chain: 10 kW hydraulic divided by ~0.1 efficiency gives about 100 kW shaft.

A: A ignores that L10 is in millions of revolutions, not hours. B still misses the cubic ratio impact since (50/5)^3 = 1000. D stretches conservatism beyond the math. C follows ISO 281: 1000 million rev divided by (1500×60) gives about 111,000 hours.