摘要:

The analysis of reactor power fluctuations has proved useful for many reactors. Limited analysis techniques giving specific noise characteristics are proposed. Utilizing the Gaussian property of reactor noise, simplified methods of obtaining the standard deviation are given. The concepts of the easily evaluated correlation times and moments of the power spectral density are applied in the noise analysis of several boiling reactors. It is shown that standard deviations of filtered reactor noise can give spectral shape information. Finally simplified analysis of narrow band spectra is discussed with regard to obtaining the resonance width.

ISSN:0029-5639    

DOI:10.13182/NSE63-A26408

出版商:Taylor&Francis    

年代:1963

数据来源: Taylor

摘要:

Techniques are developed for computing the angular thermal flux spectrum emerging from a lattice. These methods are applied to water lattices and it is found that the computed spectra are sensitive to the geometrical description of the lattice, but insensitive to the anisotropic scattering by water. The techniques are used to predict experimentally measured spectra.

ISSN:0029-5639    

DOI:10.13182/NSE63-A26409

出版商:Taylor&Francis    

年代:1963

数据来源: Taylor

摘要:

The behavior of iodine and xenon was studied during the experimental program of the Homogeneous Reactor Test to evaluate the various methods proposed for removal of these fission products to reduce the biological hazard of iodine and minimize xenon poisoning. The observed retention of both iodine and xenon in the reactor high-pressure system considerably altered design removal concepts. Only 10-25% of the iodine in the high-pressure system circulated with the fuel solution, and xenon, formed by decay of iodine adsorbed on the walls, was retained on the walls up to 10 hr before diffusing back into the circulating stream. The xenon poison fraction was found to be 0.010 at full power of 5 Mw.

ISSN:0029-5639    

DOI:10.13182/NSE63-A26410

出版商:Taylor&Francis    

年代:1963

数据来源: Taylor

摘要:

Power spectral density measurements were conducted at the Sodium Reactor Experiments (SRE) over a wide range of frequencies and at various power levels. Use of magnetic tape recording and speedup techniques permitted rapid data analysis and excellent resolution. Results were compared with oscillation tests under identical operating conditions and were found to have the same resonance structure but higher amplitude at the resonance peaks and at low frequencies. Investigation resulted in the conclusion that the reactor fission or driving spectrum deviated from white noise at some low frequency.

ISSN:0029-5639    

DOI:10.13182/NSE63-A26411

出版商:Taylor&Francis    

年代:1963

数据来源: Taylor

摘要:

Abstract operator methods are used to derive the relations between a function satisfying the generalized eigenvalue problem and its various adjoints. Several orthogonality relations are obtained.

ISSN:0029-5639    

DOI:10.13182/NSE63-A26412

出版商:Taylor&Francis    

年代:1963

数据来源: Taylor

摘要:

A generalization of quota sampling is described and a quantitative evaluation of its validity is made.

ISSN:0029-5639    

DOI:10.13182/NSE63-A26413

出版商:Taylor&Francis    

年代:1963

数据来源: Taylor

摘要:

The relative effective resonance integral of U238has been measured as a function of temperature for uranium and UO2cylinders, 0.986 and 0.973 cm diam, respectively. The Doppler coefficientsαandβare defined by:RIorefers to the effective resonance integral (excluding 1/υabsorption) at 20°C, andtoandToare 20°C and 293°K respectively.The measurements utilized the activation technique in which the induced Np239activity of a uranium bearing specimen was determined as a function of specimen temperature during irradiation.Measured values forαandβcorrected for thermal expansion, 1/υabsorption, fission activity and a deviation from a 1 /Eepithermal flux are for metalα= 1.14±0.07×10-4/oC,β= 0.53±0.03×10-2/(°K)1/2and for oxideα= 1.34±0.11×10-4/°C,β= 0.69±0.06×10-2/ (°K)1/2. The temperature increments for which these values have been obtained were 580 and 950°C for uranium metal and oxide respectively.The results presented in this report are considered to be consistent with the results of other experiments in which the activation technique was used but are lower than theoretical predictions given by Nordheim and Rosén.

ISSN:0029-5639    

DOI:10.13182/NSE63-A26414

出版商:Taylor&Francis    

年代:1963

数据来源: Taylor

摘要:

The transport approximation of the Boltzmann equation is generalized to cover the case of anisotropic scattering with energy degradation. It is shown that in such cases the approximation is a complicated integro-differential equation for the angular flux, which is still simpler to solve numerically than the original equation.

ISSN:0029-5639    

DOI:10.13182/NSE63-A26415

出版商:Taylor&Francis    

年代:1963

数据来源: Taylor

摘要:

The normal calculations of disadvantage factors in slab geometry are performed with the odd-order spherical harmonics approximations; however, by the use of the complementary even-order results in conjunction with these standard solutions, a more accurate answer can be quickly obtained. Since the even-order approximations give an apparent upper bound on the true answer, a combination of low odd and even-order solutions produces a counterconvergence effect which closely brackets the true disadvantage factor. In particular the theory of the P4calculation is presented along with various numerical parameter studies.

ISSN:0029-5639    

DOI:10.13182/NSE63-A26416

出版商:Taylor&Francis    

年代:1963

数据来源: Taylor

摘要:

In Part I, statistical fluctuations of neutron populations in reactors are analyzed by means of an appropriate theoretical model which assumes zero neutron lifetime and one group of delayed neutrons. A computational technique is developed which employs the method of characteristics to calculate probability generating functions, thereby making possible the computation of the probability distribution of power during startup of a reactor with low source. Extensive numerical results are given for such computations for a wide range of source strengths and ramp reactivity insertion rates. The special relationships of fluctuations to safety considerations are discussed. Finally, the predictions of the model are compared with Godiva weak source transient data, and empirical criteria for conservative normalization of the model are presented.

ISSN:0029-5639    

DOI:10.13182/NSE63-3

出版商:Taylor&Francis    

年代:1963

数据来源: Taylor