Research On Neutron Distribution In Reactor And Design Of Radiation Shielding

As the requirement of energy increases rapidly now, many countries think much of the clean nuclear energy, which leads the number of the nuclear power plants increases and the type of reactor innovates at the same time. As the autonomation of reactor design in our country is necessary, we should research the nuclear reactor physics of the mature reactor type and evaluate its security.In this paper the feature of reactor core physics is analyzed by means of calculation program named MCNP, including critical Keff, neutron spectrum, neutron and photon flux density distribution and power density distribution. As the volume of the reactor is huge, the flux density in reactor core and constructional component varies considerably, another method named power density is used in the deep penetrating shielding problem to calculate the average neutron flux density. This method involves universal source and have to describe the source correctly. The result indicates that the flux density distribution tallys with the fact, and the flux density in pressure vessel and area outside the vessel is more smooth, so the shielding effect is ideal.In this text the critical source is used to get the power density distribution, and the result is used in the second calculation of universal source, which supplied a logical means for the shielding calculation of huge reactor.