1. Inside the National Ignition Facility, a service system lift gives technicians access to the target chamber interior for inspection and maintenance. The chamber is a sphere 10 meters in diameter, assembled from ten-centimeter-thick aluminum panels which were preformed and then welded in place. It is covered with .3 meters of concrete which was injected with boron to absorb neutrons from the fusion reaction. The holes in the chamber permit the 192 laser beams to enter the chamber and to provide viewing ports for diagnostic tools. (NIF/Lawrence Livermore National Laboratory)
2. The single largest piece of equipment at the National Ignition Facility is its 130-ton target chamber. The design features 6 symmetric middle plates and 12 asymmetric outer plates, which were poured at the Ravenswood Aluminum Mill in Ravenswood, West Virginia. The plates were shipped to Creusot-Loire Industries in France, where they were heated and shaped in a giant press. The formed plates were then shipped to Precision Components Corp. in York, Pennsylvania, where they were trimmed and weld joints prepared. Assembly of the target chamber at Lawrence Livermore National Laboratory (seen here) was then performed in a temporary cylindrical steel enclosure. (NIF/Lawrence Livermore National Laboratory)
3. The 10-meter-diameter target chamber is lifted into place in June 1999. The spherical vacuum vessel was installed at Lawrence Livermore National Laboratory with one of the largest cranes in the world. (NIF/Lawrence Livermore National Laboratory)
4. After the target chamber was lowered into place, the seven-story walls and roof of the Target Bay were completed. (NIF/Lawrence Livermore National Laboratory)
5. Construction workers install equipment inside the target chamber at the National Ignition Facility. (NIF/Lawrence Livermore National Laboratory)
6. Concrete pedestals in the two laser bays support the beampath infrastructure system for NIF's 192 laser beams. This is one of two 96-beam laser bays that were built at the facility. (NIF/Lawrence Livermore National Laboratory)
7. This photo from January 2002 shows the installation of the National Ignition Facility power-conditioning system, which has more than 160 kilometers of high-voltage cable, which delivers energy to the system's 7,680 flashlamps. (NIF/Lawrence Livermore National Laboratory)
8. The National Ignition Facility's Laser Bay 2. The laser beams travel more than 1,000 feet before they reach the target chamber. Laser Bay 2 was commissioned on July 31, 2007. (NIF/Lawrence Livermore National Laboratory)
9. The fabrication of melted and rough-cut blanks of laser glass amplifier slabs needed for the NIF construction (3,072 pieces) was completed in 2005. The amplifier slabs are neodymium-doped phosphate glass manufactured by Hoya Corporation USA and Schott Glass Technologies for Lawrence Livermore National Laboratory. (NIF/Lawrence Livermore National Laboratory)
10. Lawrence Livermore National Laboratory technicians John Hollis (right) and Jim McElroy install a SIDE camera in the target bay of the NIF in January of 2009. The camera was the last of NIF's 6,206 various opto-mechanical and controls system modules called "line replaceable units" or LRUs to be installed. The first LRU, a flashlamp, was installed on Sept. 26, 2001. (NIF/Lawrence Livermore National Laboratory)
11. The NIF requires optics produced from large single crystals of potassium dihydrogen phosphate (KDP) and deuterated potassium dihydrogen phosphate (DKDP). Each crystal is sliced into 40-centimeter-square crystal plates. Traditionally DKDP has been produced by methods requiring approximately two years to grow a single crystal. With the development of rapid growth methods for KDP, the time required to grow a crystal has been reduced to just two months. The current rapid growth process produces optics that are up to 66cm (2 ft, 2 in) wide, 50cm (1 ft, 8 in) tall, and weighing 380 kg (840 lbs). NIF requires 192 optics produced from traditionally grown DKDP and 480 optics rapidly grown from KDP. Approximately 75 production crystals will have been grown totaling a weight of nearly 100 tons. (NIF/Lawrence Livermore National Laboratory)
12. Workers on the NIF target bay floor just outside the target chamber. (NIF/Lawrence Livermore National Laboratory/Jacqueline McBride)
13. A technician inspects the final optics inspection (FODI) system for the NIF. When the FODI is extended into the 10-meter diameter target chamber from a diagnostic instrument manipulator, it can produce images of all 192 beamline final optics assemblies. (NIF/Lawrence Livermore National Laboratory)
14. The exterior of the National Ignition Facility in in Livermore, California. Construction of the facility was completed in March 2009 and it was dedicated on May 31, 2009. (NIF/Lawrence Livermore National Laboratory)
15. The final optics assemblies, shown here mounted on the lower hemisphere of the target chamber, contain special optics for beam conditioning, color conversion, and color separation. They also focus the beams from 40-by-40 centimeter squares of light to a spot on the target only .2 to 2 millimeters in diameter. (NIF/Lawrence Livermore National Laboratory)
16. The NIF's millimeter-sized targets must be designed and fabricated to meet precise specifications for density, concentricity and surface smoothness for NIF experiments. Scientists and engineers at Lawrence Livermore National Laboratory like Richard Montesanti have developed the precision robotic assembly machine to manufacture the small and complex laser-driven fusion ignition targets. (NIF/Lawrence Livermore National Laboratory/Jacqueline McBride)
17. California governor Arnold Schwarzenegger toured the stadium-sized NIF on Nov. 10, 2008. Pictured from left: NIF director Dr. Edward Moses, Governor Schwarzenegger, LLNL Director Dr. George Miller. (NIF/Lawrence Livermore National Laboratory/Jacqueline McBride)
18. NIF's final optics inspection system, extended into the target chamber designed to produce images of all 192 beamline final optics assemblies. (NIF/Lawrence Livermore National Laboratory)
19. This view from the bottom of the target chamber shows the target positioner being inserted (spike at 7 o'clock position). Pulses from NIF's high-powered lasers race toward the Target Bay , arriving at the center of the target chamber within a few trillionths of a second of each other, aligned to the accuracy of the diameter of a human hair. (NIF/Lawrence Livermore National Laboratory)
20. The target positioner and target alignment system precisely locate a target in the NIF target chamber. (NIF/Lawrence Livermore National Laboratory)
21. A woman holds up an apparatus with the hohlraum on the end. The hohlraum is a pencil-eraser-sized cylinder that holds the target, a spherical capsule no larger than a peppercorn, destined to be bombarded with 192 powerful lasers. (NIF/Lawrence Livermore National Laboratory)
22. A gold hohlraum for use in the NIF. German for "hollow space," a hohlraum is a small hollow metal cylinder surrounding a fusion fuel capsule. In radiation thermodynamics, a hohlraum is defined as "a cavity whose walls are in radiative equilibrium with the radiant energy within the cavity." The hohlraum converts directed energy from either laser light or particle beams into X-ray radiation. (NIF/Lawrence Livermore National Laboratory)
23. A prototype 2-millimeter diameter beryllium-coated laser fusion target capsule is suspended between two ultra-thin plastic sheets used to facilitate handling of the shell. The tiny capsule will be filled with a liquid mixture of deuterium and tritium, which will then be frozen to just above 18 degrees Kelvin, or -427° Fahrenheit. Then the 192 laser beams enter the hohlraum from top and bottom, creating X-rays that heat the capsule to temperatures as high as those within the sun. This creates incredible pressures that compress the fuel contained inside the capsule, forcing the atoms inside to fuse together while releasing a tremendous burst of energy. (NIF/Lawrence Livermore National Laboratory)
24. On October 6th, 2010, the target assembly holding the hohlraum with its tiny capsule inside is mounted in the cryogenic target positioning device at the NIF. The two copper-colored arms form a shroud around the cold target to protect it until they open five seconds before a shot. (NIF/Lawrence Livermore National Laboratory)
25. A positioner precisely centers the target inside the target chamber and serves as a reference to align the laser beams. (NIF/Lawrence Livermore National Laboratory)
26. The remains of the target assembly after the October 6th, 2010 shot. The NIF's 192-beam laser system fired 1 megajoule of laser energy into its first cryogenically layered capsule. A megajoule is equivalent to the energy consumed by 10,000 100-watt light bulbs in one second. (NIF/Lawrence Livermore National Laboratory)
27. A tall composite photograph showing three stories of the target bay and many of the lasers and diagnostic devices surrounding the NIF's target chamber at center. (NIF/Lawrence Livermore National Laboratory)
The vehicle is intended to have about 20,000 kilometres (12,000 mi) range and good subsonic and supersonic fuel efficiency, thus avoiding the problems inherent in earlier supersonic aircraft. The top speed is projected to be Mach 5+. It calls for the use of liquid hydrogen as a fuel, which has twice thespecific energy of kerosene, and can be used to cool the vehicle and the air entering the engines via a precooler.
The developers say it would be able to fly from Brussels to Sydney in about 4.6 hours; compared to around a complete day of travel with normal aircraft. The cost of a ticket is intended to be roughly business class level.[1]
| “ | Our work shows that it is possible technically; now it's up to the world to decide if it wants it. | ” |
— Alan Bond, managing director of Reaction Engines Limited |
Alan Bond told The Guardian newspaper:[2]
| “ | The A2 is designed to leave Brussels International Airport, fly quietly and subsonically out into the north Atlantic at Mach 0.9 before reaching Mach 5 across the North Pole and heading over the Pacific to Australia. | ” |
Another advantage of the design is that, while the 143 metre-long A2 is much bigger than conventional jets, it would be lighter than a Boeing 747 and could take off and land on current airport runways.
However, the A2 design does not have windows. The heat generated by traveling so quickly makes it difficult to install windows that are not too heavy. One solution Reaction Engines has proposed is to install flat panel displays, showing images of the scene outside.
The Scimitar engines use related technology to the company's earlier SABRE an engine which is intended for space launch, but here adapted for very long distance, very high speed travel.
Normally, as air enters a jet engine, it is compressed by the inlet, and thus heats up. This means that high speed engines need to be made of technologies and materials that can survive extremely hightemperatures. In practice, this inevitably makes the engines heavier and also reduces the amount of fuel that can be burnt to avoid melting the gas turbine section of the engine, which in turn reduces thrust at high speed.
The key design feature for the Scimitar engines is the precooler, which is a heat exchanger that transfers the heat from the incoming air into the hydrogen fuel. This greatly cools the air, which allows the engines to burn more fuel even at very high speed, and allows the engines to be made of lighter, but more heat susceptible, materials such as light alloys.
The rest of the engine is described as having high-bypass (4:1[3]) turbofan engine features to give it good efficiency and subsonic (quiet) exhaust velocity at low speeds. Unlike SABRE the A2's engine would not have rocket engine features.
A2 2000 Ground
Takeoff 1
Inflight underneath
25km up
a2 heating
A380 compared
size comparison
With A380 Front
With A380 Side
With A380 Top
1. Combining two major ATLAS inner detector components. The semiconductor tracker is inserted into the transition radiation tracker for the ATLAS experiment at the LHC. These make up two of the three major components of the inner detector. They will work together to measure the trajectories produced in the proton-proton collisions at the centre of the detector when the LHC is switched on. Photo taken on February 22nd, 2006. (Maximilien Brice, © CERN)
2. Views of two step of an ultrasound and induction welding to interconnection between two LHC magnet at sector 3-4 during repair operation on March 26th, 2009. (Maximilien Brice, © CERN) #
3. Visible damage to the LHC magnets in sector 3-4 of the LHC on November 12th, 2008. On September 19th, 2008, as the LHC was being switched on, a faulty electrical connection between two of the accelerator's magnets caused a large helium leak, which violently vented 6 tons of helium into the tunnel. The resulting temperature rise damaged some 53 magnets. (Maximilien Brice, © CERN) #
4. Detail of some of the damage done to the LHC magnets in sector 3-4 on September 19th, 2008. (Maximilien Brice, © CERN) #
5. Moving and placement of a quadrupole at sector 3-4 in the LHC tunnel on April 30th, 2009. (Maximilien Brice, © CERN) #
6. A replacement magnet for LHC sector 3-4 being lowered in the tunnel on January 19th, 2009. (Maximilien Brice, © CERN) #
7. Moving and placement of a quadrupole at sector 3-4 in the LHC tunnel on April 30th, 2009. (Maximilien Brice, © CERN) #
8. Transporting a quadrupole through sector 3-4 in the LHC tunnel on April 30th, 2009. (Maximilien Brice, © CERN) #
9. Installation of a new dipole in the LHC tunnel at sector 3-4 on April 6th, 2009. (Maximilien Brice, © CERN) #
10. Detail of one of the LHC's 18-kW 4.5-K refrigerator units, part of the larger cryogenic system used to maintain superfluid helium temperatures of about 1.9k (-271.25° Celsius or -456.25° Fahrenheit). Photograph taken on April 28th, 2008. (Mona Schweizer, © CERN) #
11. The silicon strip tracker of the Compact Muon Solenoid (CMS) nears completion. Shown here are three concentric cylinders, each comprised of many silicon strip detetectors (the bronze-coloured rectangular devices, similar to the CCDs used in digital cameras). These surround the region where the protons collide. (© CERN) #
12. An automated magnetic tape vault at CERN computer center, seen on September 15th, 2008. The tapes are used to store the complete LHC data set, from which a fraction of the data is copied to overlying disk caches for fast and widespread access. The handling of the magnetic tape cartridges is now fully automated, as they are racked in vaults where they are moved between the storage shelves and the tape drives by robotic arms.(Claudia Marcelloni; Maximilien Brice, © CERN) #
13. Final work is done on the detectors inside the L3 magnet of the ALICE experiment on July 10th, 2008. (Mona Schweizer, © CERN) #
14. View of the CMS Detector before closure on August 17th, 2008. (Maximilien Brice; Michael Hoch; Joseph Gobin, © CERN) #
15. Portrait of Lyn Evans, LHC project Leader, on December 3rd, 2008. (Maximilien Brice, © CERN) #
16. Shielding of the L3 magnet, ALICE experiment on July 10th, 2008 (Mona Schweizer, © CERN) #
17. Final preparations on a replacement magnet ready to be lowered into sector 3-4 on November 27th, 2008. (Maximilien Brice, © CERN) #
18. A tunnel with part of one of the beam dumps of the LHC at point 6. Beam dumps are absorption mechanisms where the powerful beams can be extracted completely from the LHC, consisting of a 7m segmented carbon cylinder, 700mm in diameter, contained in a water-cooled steel cylinder, surrounded by about 750 tons of concrete and iron shielding. The sign at top warns of the presence of helium, argon and/or nitrogen in nearby pipes - gases that (if they leaked out) could displace oxygen and cause unconsciousness. (Maximilien Brice; Claudia Marcelloni, © CERN) #
19. Insertion of a Time Of Flight (TOF) module in the upper part of the spaceframe for the ALICE experiment. Charged particles in the intermediate momentum range are identified in ALICE by the TOF detector. The time measurement, in conjunction with the momentum and track length measured by the tracking detectors is used to calculate the particle mass. (Mona Schweizer, © CERN) #
20. Detail of the LHCb Magnet, seen on September 5th, 2008. (Peter Ginter, © CERN) #
21. A collimater for the LHC. The powerful LHC collimation system protects the accelerator against damage due to unavoidable regular and irregular beam loss. (Claudia Marcelloni, © CERN) #
22. View of the LHC machine in the tunnel at the junction part with the beam dump at point 6 on July 25th, 2008. (Maximilien Brice, © CERN) #
23. View of the CMS Detector before closure, on August 17th, 2008. (Maximilien Brice; Michael Hoch; Joseph Gobin, © CERN) #
24. Last views of the L3 magnet before its closure on June 28th, 2008. Installation of the mini frame of ALICE on 15 May 2009. (Maximilien Brice; Mona Schweizer, © CERN) #
25. Closing of the 30-inch-thick, 430 ton L3 door on the I side, ALICE experiment, on June 11th, 2008. (Mona Schweizer, © CERN) #
26. A radiofrequency chamber of the LHC. Radiofrequency chambers give a kick to the protons once per circuit to increase their speed. Original here. (Wikimedia user Rama / CC BY-SA) #
27. A fireman examines emergency exit signage in the LHC tunnel on February 21st, 2008, during an exercise with French, Swiss and CERN firemen. (Maximilien Brice, © CERN) #
28. Work on the ATLAS semiconductor tracker barrel. Precision work is performed on the semiconductor tracker barrel of the ATLAS experiment. The semiconductor tracker will be mounted in the barrel close to the heart of the ATLAS experiment to detect the path of particles produced in proton-proton collisions. (Maximilien Brice, © CERN) #
29. Integration of the three shells into the ATLAS pixel barrel, the innermost tracking device of the experiment. (Claudia Marcelloni, © CERN) #
30. Installing the ATLAS calorimeter in November of 2005. The eight torodial magnets can be seen on the huge ATLAS detector with the calorimeter before it is moved into the middle of the detector. This calorimeter will measure the energies of particles produced when protons collide in the centre of the detector. (Maximilien Brice, © CERN) #
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