The RZ2 was a British design for a LOX / kerosene liquid fuel rocket engine to power the Blue Streak missile.
The design was a development of the Rolls-Royce RZ1 rocket engine, which had in turn been a development by Rolls-Royce of the Rocketdyne S3D.[1]
Two variants of this engine were developed: the first provided a static thrust of 137,000 lbf (62,100 kg) and the second (intended for the three stage satellite launch vehicle) 150,000 lbf (68,000 kg). The engines were unique at that time in that they could be vectored by seven degrees in flight for guidance.
Some disconnected facts for arrangement:
The Efflux chamber of the engine was made of nickel tubes brazed together through which flowed kerosine down one tube and back up the adjacent tube via a manifold at the mouth of the chamber. After static firings these chambers were checked by climbing inside the engine from beneath (the mouth being 6 feet in diameter this was no problem, but the throat was rather smaller and more constricting. After firing the inside of the chamber was coated with fine carbon, so chamber inspection was not only filthy but had to be done in the most careful fashion as small holes in the tubes were not infrequent.) At the head of the chamber was the injector plate with concentric circles of Lox and kerosine injectors arranged in such a way that the liquids jets hit one another, like on like. The outer ring, of kerosine injectors helped cool the tubes which formed the chamber walls. From memory the lox pressure was 720 psi and the kerosine 450. The start sequence was as follows. -10 secs The start tanks were pressurized. -7.5 secs The blade valves opened to allow fuel and oxidant to flow to the gas generator and on to the pump turbines. These turbines accelerated from 0 ro 30,000rpm in 32mSecs and drove pumps through a 6 to 1 reduction gearbox which forced the propellants into the engines. -4 secs main engine burn commenced. -2.5 secs Full thrust was achieved. 0 secs Vehicle release.
Lift off was required to be at 1.3 g to enable the ground equipment to be cleared. Bearing in mind the nature of the autopilot the vehicle tended to rotate about its long axis and move laterally at release as a result of standing small corrections implemented through the vectoring of the engines. With the RZ2 Mk 3 developing 150,000 lbs of thrust this meant that the all up weight of the vehicle at lift off was about 230,000 lbs or a little over 100 tons. Because of the limited gain change abilities of the autopilot, as the weight of the vehicle fell the corrections applied by vectoring the engines were more vigorous at lighter weights and even on ground tests the engines be seen not to be entirely rigid as the mouth of the chamber moved slightly after the corrections were applied by the hydraulic rams. These rams were fed by hydraulic fluid at about 3,000 psi.
The dynamic pressure at the chamber mouth was about 6 psi.
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||