Archives: Gmedia Albums
Turbopump 3D CAD
3D CAD model images of the A4/V2 rocket engine’s steam turbine powered propellent pumps – all images by Ray Matter. To see Ray Matter’s blog 3D CAD modelling the V2 rocket turbopump introducing these images, just click the link.
A schematic drawing of the Askania rudder servo ‘Rudermaschine LRM 3’showing the critical compact dimentions of the device making it ideal for retro fit projects for smaller aircraft.
Photo shows cast aluminium thrust ring with electro-hydraulic servos in position. Note different crank lever shapes (pale green arm on servo) for fins 1/3 and 2/4 This excellent restoration is the work of Horst Beck. Photo copyright: The Horst Beck Collection
Photo shows rare surviving complete set of 8 lead acid battery cells from one of the V2 rocket’s 32 volt (100 amp) lead acid batteries. Two sets of batteries like this were used to provide the direct current (DC) voltage used aboard the V2 missile to power the DC to 3-phase alternating current (AC) generators, that in turn, powered the gyroscopes, electro-hydraulic servos, trim motors and other vital guidance and control devices. Photo copyright: The Horst Beck Collection
Photo shows a unique display at the Horst Beck Collection (HBC). Over many years Mr Horst Beck has painstakingly acquired and restored many A4-V2 missile parts – and in some cases, reassembled them into complete sub-assemblies. Shown here is part of the collection’s hydraulic servos and trim motor parts display. In the foreground we see four hydraulic servos, and behind them their A frame mounting ‘chairs’. The top shelf, from left to right, shows a servo with motor removed (and placed on its right). In the middle, two trim motors and chain sprocket gear-boxes for the aerodynamic trim surfaces on the trailing edge tips of fins 2 and 4. Next the pale green crank levers, the first longer one is for the hydraulic servo that controls the jet vanes and trimmers on fins 1 and 3. The shorter version minus the top horn, is used on the servos for fins 2 and 4. The last, silver coloured item,os a servo stabiliser (all the servos shown have one already fitted). Photo copyright: The Horst Beck Collection
Photo shows restored air-rudder and fin detail. The grey painted barrel-strainers are both adjusted independently to reduce slack in the drive chain and avoid introducing a deflection bias in the air rudder. The 1.9kg counterbalance weight normally located at the top of the trim fin (or air rudder) is missing in this presentation. This excellent restoration is the work of Horst Beck. Photo copyright: The Horst Beck Collection
Photo shows partially restored air-rudder and fin detail. The image on the left shows the relationship of the trim motor to the air rudder drive shaft on fins 2 and 4. A chain similar in gauge to the type used on a push-bike and yet, at the other end of the shaft, the chain transmitting the torque of the trim motor to the air-rudder drive sprocket has a heavy gauge chain similar to that found on a 1000CC motor-cycle! This excellent restoration is the work of Horst Beck. Photo copyright: The Horst Beck Collection
Photo shows four restored graphite jet vane support blocks and bearing housings. The round plates we can see here act as heat sinks and allow heat to radiate away from the support block and bearing to help prevent expansion due to relatively rapid and uneven temperature distribution accumulation. The graphite vanes were quite brittle and cracking caused by rapid and uneven expansion could cause the vane to disintegrate. The area around the graphite vanes was exposed to the accumulation of heat not merely as a result of duration of the motor burn time but temperature was also increased at higher rates as the jet plume expanded with the decreasing atmospheric pressure as the missile gained altitude. This excellent restoration is the work of Horst Beck. Photo copyright: The Horst Beck Collection
Wreckage of hydraulic servo from fin 2 or 4 of V2 missile that fell on a farm in Essex in March 1945. The motor has been removed and we can see details of the oil gear pump and valve control gear. The 3 position electromagnetic relay switch is visible at the 7 to 8 o’clock position within the open aperture. The push rod that connects the relay to the gear pump valves is also visible as a short brown coloured rod with a fine wire connector at each end, running in towards the gear-valves from the 9 o’clock position. The point that provides electrical current for the motor (which runs all the time and in one direction only) can be seen at the three o’clock position. The black housing has two sets of brass tongues that receive the matching brass spades mounted on the base of the motor for power input. The motor drive shaft has a female square socket coupling to connect the motor to the middle drive gear of the gear pump. A small portion of the square drive shaft of the central gear can just be seen in the photo – in the centre of the valve control block.
Hydraulic gear pump with close up detail showing ceramic heater element insulators with flat, possibly nichome, metal strip element threaded through them. This oil heating system was designed to maintain a specific viscosity of the oil regardless of environmental temperature, to better maintain oil flow rates and thus pump efficiency. The heating system is found only rarely on surviving relics.
V2 missile graphite jet vane defector replica made for V2 Rocket History.
V2 missile graphite jet vane defector replica made for V2 Rocket History. This accurate replica shows the distinctive pantograph mill tool ‘witness’ marks well.
Close-up of Askania gear pump relic with oil heaters. This picture shows an unusual feature on the otherwise normal cast aluminium base of this gear pump. The knurled knob positioned between the oil flow balance adjusters has a purpose that is unknown to us. The two oil-flow balance adjuster valves visible in the picture have slot head adjuster screws and you can also see the knurled circumference on each screw. This parallel knurling is engaged by a crease formed in the facing surface of the copper spring strips. The function of these strips is to create tactile feedback that the technician making the adjustment can feel in the handle of the screwdriver. This was done because the gear pump needed to be adjusted in a dark and narrowly confined space.
Gear pump showing flow adjusters (two slot head screws nearest bottom of picture) and ceramic heater elements situated at each end of the block. The square drive shaft coupler (corroded but still identifiable) has been highlighted in red paint. The open holes either side are the main control valve guides. The copper spring strips visible on each oil flow adjuster provide locking and tactile feed-back for the adjusting process. This relic was recovered from Usedom island.
Two Askania (designed) hydraulic gear pumps – the examples shown here have two ceramic insulators with with Nichrome wire type heating elements. The heaters are located at each end of the pump on the long axis. The pump on the right still has its power supply wires attached and was easily repaired and restored to full function in our workshop.This type of pump (with heaters) seem to be rare among the debris of European combat impact sites but fairly common in debris collections emanating from research flights in Peenemünde and parts of Poland. An explanation maybe that the oil could be warmed up sufficiently simply by starting all four hydraulic gear pumps sooner in the pre-launch sequence. The only downside being that the already noisey missile would be making yet more noise in the risky period leading up to launch.
Valves
Images of the main valves involved in the propellant flow of the A4 / V2 liquid fuelled rocket engine
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
Anatomy of the V2: 18-pot injector head
Brass liquid oxygen (LOX) spray nozzle.Note: the thread is shown in simplified graphic form. 3D model by Alexander Savochkin
Brass liquid oxygen (LOX) spray nozzle. Note: the thread is shown in simplified form. 3D model by Alexander Savochkin
One of the 18 liquid propellant (LOX and fuel) diffuser cups, showing three rows or echelons (A,D,& E) of brass injector inserts as well as two rows of drilled fuel feed holes. The LOX spray head is shown in the centre. 3D model by Alexander Savochkin
Cutaway showing echelon A with 2-part 2131E fuel injector inserts at the top of a propellant diffuser cup. Note the close proximity of the injector inserts to the simple ‘watering can’ type LOX spray head. One row of drilled fuel feed holes can be seen below the inserts. 3D model by Alexander Savochkin
This images shows a cutaway of a burner cup from outer Ring I of the injector head and shows injector insert eschelon D, & E as well as one row of drilled feed holes. Three fuel injector insert types can be seen: Top D, = 3303D (white), lower E, = 3304D (red), and E, = 3305D (blue). 3D model by Alexander Savochkin
This images shows a burner cup from outer Ring I of the injector head and the cutaway shows injector insert eschelon A,D, & E as well as two rows of drilled feed holes. Four fuel injector insert types can be seen: Top, A = 2131E, lower D, = 3303D (white), lowest E, = 3304D (red), and E, = 3305D (blue). 3D model by Alexander Savochkin
General view of the propellant diffuser cup inner core. The swirl caps of fuel injector inserts in positions A,D,& E can be seen clearly on the outside of the core as well as the central holes in the 3304D (red) inserts.The two rows of drilled fuel feed holes are also well shown. 3D model by Alexander Savochkin
Close-up detail showing independent pathway for fuel passing into injector head and fuel passed down from the head to be used for veil cooling system. Fig. A shows vertical passages for overall fuel feed to the head and Fig.B shows horizontal pathway for veil coolant fed from the head via the veil coolant distributor ring or manifold. 3D model by Alexander Savochkin
Underside view of injector head showing liquid propellant (LOX and fuel) diffuser cups, (see other images for insert and position nomenclature). Of note in this image are the pointing angles of the cups, positioned on a parabolic section to focus the propellant nebular stream into the central axis of the combustion space. Also of note are the large areas between each cup NOT employed in the injection process – initiating ‘clumpy’ and uneven propellant mixing initially below the injector face but also carried forward into the combustion space. The LOX spray head is shown in the centre of each cup. 3D model by Alexander Savochkin
Inverted view of injector head showing liquid propellant (LOX and fuel) diffuser cups, (see other images for insert and position nomenclature). Of note in this image are the pointing angles of the cups, positioned on a parabolic section to focus the propellant nebular stream into the central axis of the combustion space. Also of note are the large areas between each cup NOT employed in the injection process leading to structured propellant mixing as opposed to even homogeneous mixing. The four veil cooling inlet connectors are well shown. 3D model by Alexander Savochkin
View of injector head showing 18 liquid propellant (LOX and fuel) diffuser cups and head fuel valve seating ring at centre, (see other images for insert and position nomenclature). Visible immediately below the valve seat are the large connecting holes that allow fuel to flow from the inlet manifold and cooling jacket to the injector space (some brass injector inserts can be seen through the holes) after the head fuel valve is released to be opened by the turbo-pump supply pressure. The four veil cooling inlet connectors are well shown as are two of the outlet connection holes immediately above them. 3D model by Alexander Savochkin
View of the top of the injector head, with outer cups and pressed steel capping piece removed, showing, propellant diffuser inner cores with injector inserts and LOX supply pipe connection thread. The LOX spray head can be seen inside the LOX pipe connector. The swirl caps of fuel injector inserts in positions A,D,& E can be seen clearly on the outside of the cores and the two rows of drilled fuel feed holes are also well shown. 3D model by Alexander Savochkin
Another view of injector head showing liquid propellant (LOX and fuel) diffuser cups and head fuel valve seating ring at centre, (see other images for insert and position nomenclature). Visible immediately below the valve seat are the large connecting holes that allow fuel to flow from the inlet manifold and cooling jacket to the injector space (some brass injector inserts can be seen through the holes) after the head fuel valve is released to be opened by the turbo-pump supply pressure. The four veil cooling inlet connectors are well shown as are two of the outlet connection holes immediately above them. 3D model by Alexander Savochkin
A close-up view of the head fuel valve mounting flange (showing 12 fastener holes). Visible immediately below the top flange are the large connecting holes that allow fuel to flow from the inlet manifold and cooling jacket to the injector space (some brass injector inserts can be seen through the holes) after the head fuel valve is released to be opened by the turbo-pump supply pressure.
Exploded view showing some of the 1100 parts required for the complicated 18-pot injector head of the V2 25-ton thrust rocket engine. 3D model by Alexander Savochkin
Here the 18-pot head model has been cutaway to show the fuel cooling and fuel delivery spaces. the cooling jacket layer can be seen in the lowermost area of the head – below the centrally positioned fuel valve seat, between each cup at the lowest point, and ruining down toward the first set of veil cooling pores and the topmost coolant distributor ring. Note that the veil cooling system does not communicate with the regenerative cooling jacket and has its own feed pipes drawing fuel from the head injector space and not the cooling space. Visible immediately above the valve seat are the large connecting holes that allow fuel to flow from the inlet manifold and cooling jacket to the injector space after the head fuel valve is released to be opened by the turbo-pump supply pressure. 3D model by Alexander Savochkin
Liquid propellent (LOX and fuel) diffuser cup, showing three rings or echelons (A,D,& E) of brass injector inserts as well as two rows of drilled fuel feed holes. The LOX spray head is shown in the centre. Note the simple ‘shower head or watering can’ design of the LOX diffuser. A sealing washer can be seen fitted between the LOX diffuser and the steel cup. 3D model by Alexander Savochkin
Testing fuel injectors
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.