Simulation of the chernobyl accident

A brief history of Accident Chernobyl: Simulation of the influence of Neutron Absorbing Poisons and temperature feedback effects by Point Kinetics Equations

“…The nuclear parameters referring to the neutrons poisons are found in the study of Paganim [14]. With respect to temperature, the proportionality constant between temperature and neutron density 𝐻 = 2.5 × 10 −6 𝐾 𝑀𝑊𝑠 ⁄ and temperature coefficient of reactivity, 𝛼 = 2 × 10 −6 𝐾 −1 , found in Fletcher et al [5], are admitted.…”

“…In Fletcher et al [5], the average fuel temperature during the accident is presented, first held constant at 500𝐾, until the power excursion, exceeding 2000𝐾. In this last interval, since one does not specifically have the parameter 𝐻 and due to the events that caused drastic changes in the reactor core, which may have altered the linearity relationship between temperature and density, the parameter was estimated from a more realistic approximation of the temperature in the power excursion, obtaining a value of 𝐻 = 33 𝐾 𝑀𝑊𝑠 ⁄ and the temperature reaching about 2000𝐾 as shown in Fig.…”

“…In the literature, some works simulate the Chernobyl accident, especially in the final seconds of the power excursion, where one can highlight Fletcher et al [5], Yoshida et al [6] and Chan et al [3]. In the article by Geer et al [7], a hypothesis about the interpretation of the explosions that occurred at Chernobyl reactor 4 is presented, in which they consider that the first explosion consisted of thermal neutron mediated nuclear explosions in one or rather a few fuel channels, which caused a jet of debris that reached an altitude of some 2500 to 3000 m. The second explosion would then have been the steam explosion most experts believe was the first one.…”

“…We also want to show that a simple point kinetics model, considering only the variables mentioned, is already able to predict the occurrence of the Chernobyl accident. For a study considering spatial distribution as well as thermal-hydraulic effects we suggest consulting, for example, Fletcher et al [5], Yoshida et al [6], Chan et al [2], Parisi [8] and Geer et al [7].…”

Nuclear policy-nuclear fuels for peaceful, safer co-generation and environmentally benign applications

“…Here, Λ is called neutron regeneration time =0.064ms and is known as effective delayed neutron fraction [3].The simulation studies by Fletcher et al revealed that reactivity jumped rapidly to ~1.5$ at the highest power level during the transient [4]. This is due to the rise in positive void coefficient reactivity value by 20-30 pcm after insertion of control rods which introduced the negative temperature coefficient of reactivity.…”