The Earthquake Early Warning System of the Armenian Nuclear Power Plant
The idea of increasing the operation reliability of the Armenian Nuclear Power Plant (ANPP) via the radio-seismic system of NPP initial shutdown (RSIS) is intended to ensure the initial shutdown of the NPP should a strong earthquake occur. This represents
- PDF / 639,295 Bytes
- 3 Pages / 595 x 791 pts Page_size
- 52 Downloads / 214 Views
The Earthquake Early Warning System of the Armenian Nuclear Power Plant FRIDRIKH ARAKELYAN, HRAHAT HAKOBYAN
Institute AtomEnergoSeismic Project, Yer HPS-2, Hrazdan Canyon, Yerevan 375015, Armenia, E-mail: [email protected]
The idea of increasing the operation reliability of the Armenian Nuclear Power Plant (ANPP) via the radio-seismic system of NPP initial shutdown (RSIS) is intended to ensure the initial shutdown of the NPP should a strong earthquake occur. This represents essentially an upgrade of the currently applied systems of industrial anti-seismic protection, with the additional use of radio-communication means. It essentially involves the creation of a radioseismic station (RSS) network around the NPP (or any other object to be protected) located at a certain distance from the plant, in order to transmit a signal regarding seismic hazard through radio channels. Activation of the system takes place when a threshold ground acceleration is exceeded at any RSS when this occurs a signal of first class emergency protection system activation (A3-I) is automatically transmitted to the plant. Thus, due to the difference between velocities of seismic and radio waves, an early warning on seismic hazard is given. The main indicator of system effectiveness is the time of prior warning .M, which arises from the distance from an RSS to the NPP travelled by the seismic wave, more precisely, the difference of the distances: hypocentre - NPP, and hypocentre - RSS. The time spent in radio-wave transfer and system activation can be neglected. Figure 1 indicates the plan of epicentre location relative to RSS and NPP, and a simplified scheme of seismic wave passage from the source to NPP and RSS. To calculate ~t from Fig. 1 the following formulas can be used: ~t =
h/V(1/ sin a- 1/ sin p); a:::;
where V is seismic wave velocity, or
P
(1)
,M
= 1/V((Lz + h2)112 _ (Mz + h2)112) , M
Data Loading...
