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The chart shows water delivery in litres per minute per injector

Each burner cup of the V2 rocket engine injector system has forty-four brass inserts, but each cup also has twenty-four 2mm diameter plain holes, 30 deg apart, drilled into the cup’s central wall. To mimic this for testing purposes, we created a brass insert that has a base with just a 2mm central hole. The base is sized to be consistent with the 4 to 5mm cup wall. V2RH image

V2 rocket engine fuel injector inserts – a part of our collection used for the water tests with various types shown. The tool shown is a pin-wrench used to fit the inserts into the test apparatus. V2RH collection image

3305D fuel injector insert showing swirl cone nebular, and 4 steady steams emanating from cooling pores.

3305D fuel njector insert showing comparison nebular and jet stream pattern with high and low pressure. Left image shows correct hollow cone-shaped aerosol effect from central 6mm orifice, that is also creating a fine mist around and within the cone, and 4 steady steams emanating from cooling pores. Right image shows the effect of reduced pressure: a dropping poorly formed cone, composed of larger slower moving droplets, and a tendency for the thicker spray to combine and cause ‘dribbeling’ with much fluid failing to clear the injector face.

3304D higher volume fuel injector insert (with three inlet apertures: 2 swirl, 1 jet) showing swirl cone nebular, steady central jet, and 4 steady steams emanating from cooling pores.

Standard fuel injector inserts for production series 18-pot injector head. Insert 1 (3304D/3305D) shows four thin wires demonstrating the angles of all four ‘cooling’ pores. Insert 2 (3305D/2131E) has two 1.3mm twist drill showing the edge bores for the gyroscopic swirl inlets. Insert 3 (3305D) shows another view of the cooling pore angle and origin. V2RH image

V2 Fuel Injector insert: part code 2131E from injector pot echelon A (nearest to LOX spray head). The push-together two part construction of the insert is shown here. The two parts were pushed together in a specially shaped tool set that compressed the thin skirt on the female part into a recess cut into the male part. The failure test for this component required that the mated parts resist a separating force of 300kg. The two part design was dictated by the small size of the 2mm exit orifice and the funnel shaped introduction to the exit orifice. In the case of the other three standard inserts, the large 6mm exit orifice allowed a sub 6mm milling cutter, with a thin support shaft and a top chamfer, to be used in such a way that the area below the exit orifice could be undercut to create an injector cavity with a diameter larger than the 6mm entry point.

Fuel injector inserts for production series 18-pot injector head showing general shape and thread position. For further details see associated image. The lowermost insert have been halved to reveal the cavity shape, orifice edge, inlet and cooling apertures. V2RH image

Single nozzle insert test rig used by V2 Rocket History to test spray shape and volume at supply pressures consistent with fuel pressures specified for the injector head of summer 1944. The test system features an adjustable pressure regulator and fluid pressure gauge. For test purposes the device was simply connected to a relatively high pressure mains water supply. And although water does not have the same viscosity of the 75% Ethenol to 25% water mix of the V2’s fuel it was considered close enough by the German technicians, who regularly used plain water as a substitute when testing issues related to furl flow rather than combustion. A 2131E fuel injector insert is shown installed in the holder at the front of the rig, but as the thread was the same on all inserts the nozzle can be changed for other models easily with aid of a pin spanner. See video for a demonstration of this simple test system.

Single nozzle insert test rig used by V2 Rocket History to test spray shape and volume at fluid supply pressures consistent with fuel pressures specified for the injector head of summer 1944. A 2131E fuel injector insert is installed in the holder at the front of the test rig, but as the thread was the same on all inserts the nozzle can be changed for other models easily with aid of a pin spanner. See video for a demonstration of this simple test system.

3305D injector insert showing larger low-velocity droplets and ‘dribbly’ performance due to insufficient pressure. The cone shaped aerosol is not functioning. Broken streams can be seem emanating from the four cooling pores.

3305D injector insert showing comparison nebular and jet stream pattern with high and low pressure. Top image shows correct hollow cone-shaped aerosol effect, from central 6mm orifice, that is also creating a fine mist around and within the cone, and steady steams emanating from cooling pores. Bottom image shows the effect of reduced pressure: a dropping poorly formed cone, composed of larger slower moving droplets, and a tendency for the thicker spray to combine and cause ‘dribbeling’ with much fluid failing to clear the injector face – unlike the image above, where the injector face is clear of drips.

Image shows a correctly formed nebular cone attended by a fine mist. the four injector cooling jets are well shown, and although fluid beading can be seen on the face of the injector, there is insufficient liquid to cause dripping.

Single fuel injector water test rig showing a 3305D bress insert about to be tightened home using a pin-wrench. V2RH image

3304D higher volume injector insert (with central jet) showing comparison nebular and jet stream pattern with high and low pressure. Top image shows correct hollow cone-shaped aerosol effect from central 6mm orifice, that is also creating a fine mist around and within the cone, and strong single central (non-swirl) jet can be seen as well as 4 steady steams emanating from cooling pores. Bottom image shows the effect of reduced pressure: a dropping poorly formed cone, composed of larger slower moving droplets, and a tendency for the thicker spray to combine and cause ‘dribbeling’ with much fluid failing to clear the injector face. The appearance of central jet however seem largely unchanged.

Relic of prototype A4 25-ton 1940/41 aluminium injector head basket (or pre-chamber) showing 68 copper alloy inserts in 5 rows. The standard configuration would later become 44 inserts in 3 rows 25 2mm diameter drilled holes in two rows situated at row 3 and 4 (counting from nearest the camera). Photo courtesy Host Beck Collection

Parts of the ‘Standard’ series A aluminium head from 1941. The brass injector insert type and position pattern on the relics seem to be of the standard type but the pattern is non-standard in that higher volume injectors with three inlet apertures (two centrifugal and one central) have been place nearest the LOX
injector. Photo courtesy Horst Beck

Relics of the A4 25-ton 1941 aluminium injector head. See other photos in this series for more detail. Photo courtesy Horst Beck Collection

Part of the ‘Standard’ series A aluminium head from 1941 to early 1942. Showing the position of standard type LOX injector. The brass fuel injector inserts type and position pattern on the relic seem to be of the standard type with the row of 3 inlet aperture type inserts positioned furthest from the LOX injector. Photo courtesy Horst Beck Collection

Relic of A4 25-ton 1940/41 aluminium injector head basket (or pre-chamber) showing 68 copper alloy inserts in 5 rows. The standard configuration would later become 44 inserts in 3 rows 25 2mm diameter drilled holes in two rows situated at row 3 and 4 (counting from nearest the camera). Photo courtesy Host Beck Collection

25-Ton aluminium injector head showing mpe armament code for the Heimat-Artillerie-Park 11 (HAP11) Karlshagen Werk Nord.

Injector head relic from February 1945 showing injector insert type and pattern. Photo www.v2rockethistory.com

Flown V2 thrust chamber relic from February 1945. Badly damaged from impact, this head shows 4 intact LOX input pipe connections as well as exposed fuel injector inserts positioned in the inner wall of the injector pots. The inner and outer walls of the head are also conveniently exposed on this exhibit. Photo www.v2rockethistory.com

V2 Rocket History Museum Relic: This cutaway presentation shows one of the V2’s 18 combined fuel and liquid oxygen (LOX) injector ‘pots’. The LOX injector transit cap is also shown. The pot shown here is sometimes incorrectly referred to as a pre-burner or pre chamber – a mixer or diffuser pot probably describes its role more accurately.

This relic from the V2 Rocket History collection shows a cutaway presentation of one of the V2’s 18 combined fuel and liquid oxygen (LOX) injector ‘pots’. The LOX injector transit cap is also shown fitted over the LOX injector.

One of the V2’s 18 injector pots showing fuel and LOX injector copper alloy inserts. The spray head A is for liquid oxygen (LOX) and the numerous small injectors lining the chamber are for the fuel. The term pre-chamber is a throw-back to a time when combustion systems developed at the Kummersdorf test facility had a closed structure rather than the open bucket design seen here. Image Horst Beck Collection

V2 engine part from a missile fired from Walcheren, Serooskerke, Vrederust, by battery no 444, at around 7am on September 17th 1944. The missile impacted East Ham with a direct hit on houses. Killing 6 people with 15 seriously injured. Much of the rocket debris was taken to the East Ham police station for examination by the military authorities. Information porovided by www.v2rocket.com.

Examination of V2 missile thrust chamber. Sections of two of the large bore aluminium alcohol inlet manifold feed pipes and two thin steel veil colling supply pipes are still attached. The distinctive heat expansion relief loop can be seen on one of the pipes.

Image shows interior of production series (combat relic) V2 missile propellent injector pre-mixer pots. Three post in the picture are intact, others seem in the picture have been destroyed in the impact. This engine part was recovered from a combat impact East of London. Impact date: February 1945

Recovered from Great Warley impact: February 1945. This chamber has a production use order number of 33 painted crudely on topmost segment. This number, to indicate rank in batch, was added shortly after manufacture to ensure the chamber was selected by the missile assembly crews in the correct order; that is on a newest-last basis to make sure that the oldest chambers were employed in missile construction operations first.

Incomplete V2 missile on rail transporter. All 4 control compartments are well shown. The fuel tank connection pipe can be seen but not much else. All of the control equipment has been removed. Plainly visible is the chicken wire holding the fiber wool tank insulation in place. Today this would be called ‘Galvanised hexagonal network restraining matrix, and be supplied by a blue chip Aerospace company for $800 per square inch. In the 1940s, it was just chicken wire at a 2 dollars for a 100 ft roll.

Control compartments 1 (upper) & 4 (lower) Image copyright Imperial War Museum

Control compartments 3 showing gyro mounting platform with two gyros and DC motor driven 3 phase AC voltage generator. The alcohol tank pressurisation pipe is also shown running through the equipment bay (large silver coloured pipe). Image copyright Imperial War Museum

Control compartments 1. Image copyright Imperial War Museum

Control compartment 2 showing plywood separation panels, Oemig umformer (DC to 3 phase AC voltage generator), and voltage frequency control box. Towards the rear the ground connection plugs can just be seen and the mechanism of the cable release trap door (see cat flap!). Image copyright Imperial War Museum

Control compartment 1 top right, 2 top left, 3 bottom left, and 4 bottom right. The fuel tank pressurisation pipe upper connection point is well shown at about 6 o’clock (compartment 3) and just above and to the right the upper plate of the air (N) tank rack (tan colour). Image copyright Imperial War Museum
showing plywood separation panels, Oemig umform