Cooling
Injectors are commonly laid out so that a fuel-rich layer is created at the combustion chamber wall. This reduces the temperature there, and downstream to the throat and even into the nozzle and permits the combustion chamber to be run at higher pressure, which permits a higher expansion ratio nozzle to be used which gives a higher ISP and better system performance. A liquid rocket engine often employs regenerative cooling, which uses the fuel or the oxidiser to cool the chamber and nozzle.
Read more about this topic: Liquid-propellant Rocket
Famous quotes containing the word cooling:
“A little cooling down of animal excitability and instinct, a little loss of animal toughness, a little irritable weakness and descent of the pain-threshold, will bring the worm at the core of all our usual springs of delight into full view, and turn us into melancholy metaphysicians.”
—William James (1842–1910)
“As a bathtub lined with white porcelain,
When the hot water gives out or goes tepid,
So is the slow cooling of our chivalrous passion,
O my much praised but-not-altogether-satisfactory lady.”
—Ezra Pound (1885–1972)
“her in her cooling planet
Revere; do not presume to think her wasted.”
—William Empson (1906–1984)