Safety evaluation of the HTTR

Kunitomi, Kazuhiko; Nakagawa, Shigeaki; Shiozawa, Shusaku

doi:10.1016/j.nucengdes.2004.08.028

Cited by 15 publications

(9 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this event, the overheating of RPV by the hot primary coolant which might flow up from the core by natural convection is a main concern. In HTTR, it was evaluated that the RPV temperature can be maintained lower than the temperature limit in the event of LOFC by the thermal shield equipped at the top head hemispherical closure of RPV [20]. The temperature limit of RPV of HTR50S in the event of AOO (e.g., loss of off-site power) decreases relatively largely, from 500 ∘ C of HTTR to 425 ∘ C, by the design change of RPV material from 2.25Cr-1Mo steel used for HTTR to Mn-Mo steel, whereas the reduction of temperature limit of RPV is from 550 ∘ C of HTTR to 540 ∘ C in the event of the accident.…”

Section: Reactormentioning

confidence: 99%

A Small-Sized HTGR System Design for Multiple Heat Applications for Developing Countries

Ohashi

Satō

Goto

et al. 2013

International Journal of Nuclear Energy

View full text Add to dashboard Cite

Japan Atomic Energy Agency has conducted a conceptual design of a 50 MWt small-sized high temperature gas cooled reactor (HTGR) for multiple heat applications, named HTR50S, with the reactor outlet coolant temperature of 750°C and 900°C. It is first-of-a-kind of the commercial plant or a demonstration plant of a small-sized HTGR system to be deployed in developing countries in the 2020s. The design concept of HTR50S is to satisfy the user requirements for multipurpose heat applications such as the district heating and process heat supply based on the steam turbine system and the demonstration of the power generation by helium gas turbine and the hydrogen production using the water splitting iodine-sulfur process, to upgrade its performance compared to that of HTTR without significant R&D utilizing the knowledge obtained by the HTTR design and operation, and to fulfill the high level of safety by utilizing the inherent features of HTGR and a passive decay heat removal system. The evaluation of technical feasibility shows that all design targets were satisfied by the design of each system and the preliminary safety analysis. This paper describes the conceptual design and the preliminary safety analysis of HTR50S.

show abstract

Section: Reactormentioning

confidence: 99%

A Small-Sized HTGR System Design for Multiple Heat Applications for Developing Countries

Ohashi

Satō

Goto

et al. 2013

International Journal of Nuclear Energy

View full text Add to dashboard Cite

show abstract

“…The evaluation results were described in Section 3 in the same Nuclear Engineering and Design issues (Kunitomi et al, 2004). Table 6b Selected events for accidents Channel blockage in fuel block ACD-2 Rupture of inner pipe of concentric pipe in primary cooling system ACD-3…”

Section: Selection Of Eventsmentioning

confidence: 99%

“…The safety evaluation of the HTTR proved that the fuel failure by temperature increase and oxidation is limited even in the hypothetical accident (Kunitomi et al, 2004). This was well understood technically by the regulatory members, however it was pointed out that it would take another couple of years to re-examine the implementation of no containment vessel reactors.…”

Section: Containment Vesselmentioning

confidence: 99%

See 1 more Smart Citation

Safety design

Kunitomi¹,

Shiozawa²

2004

Nuclear Engineering and Design

Self Cite

View full text Add to dashboard Cite

JAERI established the safety design philosophy of the HTTR based on that of current reactors such as LWR in Japan, considering inherent safety features of the HTTR. The strategy of defense in depth was implemented so that the safety engineering functions such as control of reactivity, removal of residual heat and confinement of fission products shall be well performed to ensure safety. However, unlike the LWR, the inherent design features of the high-temperature gas-cooled reactor (HTGR) enables the HTTR meet stringent regulatory criteria without much dependence on active safety systems. On the other hand, the safety in an accident typical to the HTGR such as the depressurization accident initiated by a primary pipe rupture shall be ensured. The safety design philosophy of the HTTR considers these unique features appropriately and is expected to be the basis for future Japanese HTGRs.This paper describes the safety design philosophy and safety evaluation procedure of the HTTR especially focusing on unique considerations to the HTTR. Also, experiences obtained from an HTTR safety review and R&D needs for establishing the safety philosophy for the future HTGRs are reported.

show abstract

“…High Temperature Gas-cooled Reactors (HTGRs) have characteristics of 4th generation reactors, it is especially excellent in the safety features [1][2][3]. These safety features have already been sufficiently demonstrated [4][5][6].…”

mentioning

confidence: 99%

Transient pressure analysis for the reactor core and containment of a HTGR after a primary loop pressure boundary break accident

Shi

et al. 2011

Chin. Sci. Bull.

View full text Add to dashboard Cite

The pressure variances in the reactor core and containment of a High Temperature Gas-cooled Reactor (HTGR) after a primary loop pressure boundary break accident determine the structural integrity and safety of the reactor. Based on mass conservation, energy conservation and state equations, explicit formulae for the transient pressure and temperature variances in the pressure vessels were deduced, and a set of differential equations for the transient pressure and temperature variances in the containment were developed. Numerical simulation was also conducted to investigate the transient pressure and temperature variances in the pressure vessels and containment. The results show that energy transformation due to expansion work cannot be neglected. The maximum pressure in the containment could increase by 40 percent due to blockage caused by air in the containment. Detailed numerical simulations of the transient pressure and temperature variance in the reactor core flow passages were also conducted. The results show that the pressures acting on the reactor core and containment are below acceptable values. transient pressure, theoretical analysis, numerical simulation, high temperature gas-cooled reactor, porous media, containment Citation:Li X W, Li X T, Shi L, et al. Transient pressure analysis for the reactor core and containment of a HTGR after a primary loop pressure boundary break accident.

show abstract

Safety evaluation of the HTTR

Cited by 15 publications

References 1 publication

A Small-Sized HTGR System Design for Multiple Heat Applications for Developing Countries

A Small-Sized HTGR System Design for Multiple Heat Applications for Developing Countries

Safety design

Transient pressure analysis for the reactor core and containment of a HTGR after a primary loop pressure boundary break accident

Contact Info

Product

Resources

About