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Current article at work

My partner Manny and I will be working on this article Advanced heavy-water reactor.

References

http://www.sciencedirect.com/science/article/pii/S0306454911001022

http://web.a.ebscohost.com/ehost/detail?vid=3&sid=d332fa7e-5329-4c62-a476-1496f8d3539e%40sessionmgr4002&hid=4114&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#db=aph&AN=85285423

http://www.sciencedirect.com/science/article/pii/S0960897402000244

http://www.sciencedirect.com/science/article/pii/S0029549301004204

http://search.proquest.com/abicomplete/docview/459767322/631BAEBC59594F41PQ/8?accountid=10353

Background:(New)

Bhabha Atomic Research Centre(BARC) set up a large infrastructure to facilitate the design and development of these Advanced Heavy Water reactors. Things to be included range from materials technologies, critical components, reactor physics, and safety analysis. Several facilities have been set-up to experiment with these reactors.The AHWR, which is a pressure tube type of heavy water reactor. The Government of India, Department of Atomic Energy(DAE), is fully funding the future development, the current development, and the design of the Advanced Heavy Water Reactor.

Future Plans(New)

The new version of Advanced Heavy Water Reactors will be equipped with more general safety requirements. India is the base for these reactors due to India's large Thorium reserves; therefore, it is more geared for continual use and operation of the AHWR..

Description or Design:(Existing)

Reactor Core

The overall design of the AHWR is to utilize large amounts of thorium and the thorium cycle. The AHWR is much like that of the Pressurized heavy water reactor(PHWR), in that they share similarities in the concept of the pressure tubes and calandria tubes, but the tubes' orientation in the AHWR is vertical, unlike that of the PHWR. The AHWR's core is 3.5 m long and has 513 lattice locations in a square pitch of 225 mm. The core is radially divided into three burn up regions. The burn up decreases as it moves toward the external surface of the core. Fuel is occupied by 452 lattice locations and the remaining 37 locations are occupied by shutdown system-1. This consists of 37 shut-off rods, 24 locations are for reactive control devices which are consisted of 8 absorber rods (AR's), 8 shim rods(SR's), and 8 regulating rods (RR's). By boiling light water at a pressure of 7 MPa, heat is then removed. The main focus with this model is to get the total power and a coarse spatial power distribution within the core to be within certain degree of accuracy .

Fuel cycle:(New)

The AHWR at standard is set to be a closed nuclear fuel cycle because this will lead to reduction in radio-toxicity.Because of this, the AHWR has alternate fuel options, giving it has diverse fuel cycles. It can do closed types and once-through types of fuel cycles. The overall aspect of the AHWR is primed for high burn up with thorium-based fuel(barc, 2013). Recycled thorium that is recovered from the reactor is then sent back, and plutonium is stored to be later used for a fast breeder reactor.

Safety Innovation:(New)

Past nuclear meltdowns such as Chernobyl and Fukoshima have made the improvement of construction and maintenance of facilities to be crucial. These accidents were with the involvement of uranium-235 reactors and the poor structures of the facilities they were in. Since then International Atomic nuclear Association has stepped up protocols in nuclear facilities in order to prevent these accidents from occurring again. One of the top security measures for a meltdown is containment of radioactivity from escaping the reactor. The Defense in Depth (DiD) is a method used in nuclear facilities to acquire the most effective practice of radioactive containment. The AWHR has acquired the Defense in Depth process which is used in reactors by providing a list of provisions and required equipment in order to retain the radioactivity in the core. The Defense in Depth method sets regulations that must be followed in order to reduce human error incidents and machine malfunctions.

The procedures are the following: Level 1: Prevention of abnormal operation and failure, Level 2: Control of abnormal operation and detection of failure, Level 3: Control of accidents within the design basis, Level 4: Control of severe plant conditions, including prevention of accident progression and mitigation of consequences of severe accidents, Level 5: Mitigation of radiological consequences of significant release of radioactive materials.The AWHR is a innovation in renewable energy safety as it will limit the use of uranium-235 and substitute the element with thorium. The extraction of nuclear energy from the 90th element Thorium is set to have more energy than the world's oil, coal, and uranium united. The AHWR has safety features that distinguishes it from normal nuclear reactors. Some of these features consist of: strong safety systems, reduction of heat from core through a built in cooling system, multiple shutdown systems, and a fail-safe procedure that consist of a poison that shutdowns the system in the case of a technical failure(FBR). The potential threat scientist try to avoid in reactors is the buildup of heat because nuclear energy escalates when it reacts with, high temperatures, high pressures, and chemical reactions. The AHWR has features that helps reduce the probability of this occurrence through the: negative reactivity coefficients, low power density, low excess reactivity in the core, and proper selection of material, attributes built in.