How did they deliver one ton of fuel to the Saturn V every second?

The Saturn V rocket used a combination of pumps and turbopumps to deliver fuel to the engines at a high rate. The first stage, the S-IC, used five F-1 engines, each of which required about 1 ton of fuel per second. The fuel was stored in the rocket’s fuel tank and delivered to the engines through a system of pipes and pumps.

The pumps were driven by turbines, which were powered by the rocket’s own fuel. This is known as a turbopump. These pumps were capable of delivering fuel at a high enough pressure and flow rate to support the rocket’s engines, allowing the Saturn V to achieve its high thrust and lift the spacecraft into orbit.

The Saturn V’s F1 rockets each had a fuel pump powered by a secondary rocket engine. This secondary engine produced as much thrust as an F-16 fighter plane.

The exhaust from the fuel pump engine was ducted into the main exhaust bell. (The bottom arrow indicates the ducting.)

Since the secondary exhaust was lower in temperature than the exhaust from the main engine, it actually protected the rocket bell by forming a layer of cooler gas.

You can see this layer in the picture below: The central white/yellow exhaust from the main engine is surrounded by a darker grey/black curtain. This is the exhaust from the fuel pump.

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Each F-1 rocket engine consumed 3 tons of propellant (kerosene and oxygen) per second. The entire S-IC first stage consumed 15 tons per second.

That fuel was delivered from the fuel and oxygen tanks directly forward of the engines.

Each engine fed part of its propellant to a gas generator which drove a turbine generating 55,000 shaft horsepower, enough to drive the 3 tons per second of a pair of turbopumps into the combustion chamber at 129 atmospheres pressure.

The tanks were filled before launch via pipes running along a swing arm from the service gantry.

Summary

Each F-1 rocket engine consumed three or four tons of reactants per second. In order to do this required very powerful turbopumps, which developed thousands of horsepower each and were actually powered by their own rocket engines. 

According to Wikipedia: A gas generator was used to drive a turbine that drove separate fuel and oxygen pumps, each feeding the thrust chamber assembly.

The turbine was driven at 5,500 RPM, producing 55,000 brake horsepower (41 MW).

The fuel pump delivered 15,471 US gallons (58,560 liters) of RP-1 per minute, while the oxidizer pump delivered 24,811 US gal (93,920 l) of liquid oxygen per minute.

The thrust from the turbopump gas generator would have propelled a small plane (or a medium-sized one); that’s how powerful they were.

If you are interested in similar topics like this one, you can read my article about Rocketdyne F1 Engine by clicking here.

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