Rocketman & PWMaster
Rocketman Rocketman
Got a 500 kN engine prototype that’s blowing the launch window like a bad burn, but the heat soak is a nightmare. Ever thought about a forced‑air cooling loop for a rocket chamber? I could use a system as precise as your fan array to keep the chamber from melting.
PWMaster PWMaster
Sure thing. A forced‑air loop on a 500 kN chamber needs a few key numbers: keep the chamber wall temperature below 950 °C, that’s a heat flux of roughly 4 kW/cm² at peak. I’d run a copper cooling plate in contact with the liner, tap it with a 50 cm long fan array running at 8 kRPM. That gives you about 0.8 kg/s of air, enough to pull 5 kW of heat away if you use a heat‑transfer coefficient of 250 W/m²·K. Wire color‑code everything – green for inlet, red for outlet, blue for control – and keep a log of pressure drop; you’ll want less than 3 bar across the loop. Remember to use a 100 V fan rated for 500 °C air; the 3.3 W/100 V DC model from TDK is reliable. If you stack the fans in a serpentine layout, the static pressure will stay low and the fan life goes up. That’s the gist, keep it tight and you’ll shave the burn time by a few seconds.