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00919 Identification and properties of the fundamental expansion functions for neutron transport in an infinite homogeneous medium
14 Fuel science and technology (fundamental science, analysis, instrumentation) 06/00915 Distribution network reconfiguration for loss reduction by ant colony search algorithm Su, C.-T. et al. Electric Power Systems Research, 2005, 75, (2 37, 190 199. This p a p e r introduces an ant colony search algorithm (ACSA) to solve the optimal network reconfiguration problem for power loss reduction. The A C S A is a relatively new and powerful intelligence evolution m e t h o d for solving optimization problems. It is a population-based approach that uses exploration of positive feedback as well as greedy search. The A C S A was inspired from natural behaviour of the ant colonies on how they find the food source and bring them back to their nest by building the unique trail formation. By applying the ACSA, the n e a r - o p t i m a l solution to the network reconfiguration problem can be effectively achieved. The A C S A applies the state transition rule, local p h e r o m o n e - u p d a t i n g rule, and global p h e r o m o n e - u p d a t i n g rule to facilitate the computation. The network reconfiguration problem of one three-feeder distribution system from the literature and one practical distribution network of Taiwan Power C o m p a n y (TPC) are, respectively, solved using the proposed A C S A method, the genetic algorithm (GA), and the simulated annealing (SA). N u m e r i c a l results show that the proposed m e t h o d is better than the other two methods.
06/00916 Effects of the Laurent and Taylor expansions on the calculations of the thermal neutrons inelastic scattering cross sections for crystalline moderators Difilippo, F. C. and Renier, J. P. Annals of Nuclear Energy, 2005, 32, (127, 1323 1336. The use of updated p h o n o n spectra for the calculation of the scattering matrix, S(c~,/3,T7, of graphite made a p p a r e n t discrepancies more related to numerical artifacts than to genuine differences. C o m p a r i n g results from the use of the codes G A S K E T and L E A P R , with improved p h o n o n spectra, the authors found consistent results only when a consistent a s y m p t o t i c region a r o u n d zero frequency is used. This effect is produced by a second order pole at frequency zero that appears during the calculation of S(c~,/3,T7 via a double Fourier transform. The pole also affects the q u a d r a t u r e s at higher frequencies so it became n a t u r a l to use the Laurent expansion rather than Taylor's for a more robust numerical method. The results of this analysis were included in the local version of the codes G A S K E T and L E A P R .
06/00917 Effects of viscous dissipation on the heat transfer in a forced pipe flow, Part 2: Thermally developing flow Aydin, O. Energy Conversion and Management, 2005, 46, (18 197, 3091 3102. In this part of the study, consideration is given to thermally developing laminar forced convection in a pipe including viscous dissipation. The axial heat conduction in the fluid is neglected. Two different t h e r m a l b o u n d a r y conditions are considered: the constant heat flux (CHF) and the constant wall t e m p e r a t u r e (CWT). Both the wall heating (the fluid is heated) case and the wall cooling (the fluid is cooled) case are considered. The distributions for the developing t e m p e r a t u r e and local Nusselt n u m b e r in the entrance region are obtained. Results show that the t e m p e r a t u r e profiles and local Nusselt n u m b e r are influenced by the B r i n k m a n n u m b e r (Br7 and the thermal b o u n d a r y condition used for the wall. Significant viscous dissipation effects have been observed for large Br.
06/00918 Experimental and numerical study of threedimensional flow field in mini-environment Cheng, C.-S. and Hung, J.-S. Energy and Buildings, 2005, 37, (67, 579 586. This study is concerned with t h r e e - d i m e n s i o n a l air flow field for improving the ventilation performance of a m i n i - e n v i r o n m e n t in which toxic gas is produced during the coating process. To investigate the air flow field, m e a s u r e m e n t for the velocity distribution has been m a d e by using a t h r e e - d i m e n s i o n a l ultrasonic a n e m o m e t e r , and n u m e r i c a l simulation using c o m p u t a t i o n a l fluid dynamics (CFD) analysis tool has also been performed. Results of the numerical simulation based on the R N G k c turbulence model are confirmed by the experiments, and modifications in geometric configuration of the system are investigated. It is found that the numerical and experimental approaches used in this study lead to useful i n f o r m a t i o n of flow field and the ventilation performance in the mini-environment may be greatly improved by adjusting the location of the H E P A and modifying the shape of the inlet of the exhaust pipe.
06/00919 Identification and properties of the fundamental expansion functions for neutron transport in an infinite homogeneous medium Milgram, M. S. Annals of Nuclear Energy, 2005, 32, (11), 1167 1190. Starting from the basic expression for the neutron flux due to a point source in an infinite h o m o g e n e o u s scattering and absorbing medium, the first few f u n d a m e n t a l expansion functions corresponding to successive collisions are identified, and their analytic properties are presented, in spherical and plane geometry. Various representations of
134
Fuel and Energy Abstracts
March 2006
the functions are obtained in the form of power series, an expansion in a series of exponential integrals, and other integrals. The adequacy of traditional asymptotic forms is considered.
06/00920 Inverter topologies for DSTATCOM applications a simulation study Iyer, S. et al. Electric Power Systems Research, 2005, 75, (2 37, 161 170. This paper describes a few different topologies of inverters used for realizing a distribution static c o m p e n s a t o r ( D S T A T C O M ) . A brief introduction of the need for s h u n t c o m p e n s a t i o n as well as the r e q u i r e m e n t s of the shunt c o m p e n s a t o r has also been given. A n algorithm for generating references has been described. Three major topologies of inverters three-leg inverter with single dc capacitor, three-leg inverter with neutral clamped dc capacitors, four-leg inverter and three single-phase inverters with c o m m o n dc capacitor have been described and simulated. D S T A T C O M topologies for high voltage distribution systems have also been described. The voltage source converter (VSC) topologies have been c o m p a r e d on the basis of the performance of the inverter for certain chosen system conditions and the n u m b e r of switch devices and dc capacitors used. All simulations have been performed using P S C A D / E M T D C .
06/00921 Linear and quadratic octahedral wavelets on the sphere for angular discretisations of the Boltzmann transport equation Buchan, A. G. et al. Annals of Nuclear Energy, 2005, 32, (117, 1224 1273. In this paper, two new wavelet bases are developed for discretizing the angular term of the first-order Boltzmann t r a n s p o r t equation. The wavelets proposed are based on Swelden's second-generation wavelets, which are constructed through the lifting procedure. In this paper, the wavelets are built on an octahedral d o m a i n and the angular flux approximation takes the form of finite e l e m e n t linear and quadratic representations. Full details of the meshing over the o c t a h e d r o n and derivation of the wavelet functions are given. The wavelets discussed are similar to the wavelets developed in the earlier studies where the bases use a new f u n d a m e n t a l a m e n d m e n t for mitigating the inaccuracies observed with the earlier bases. The performance of the new angular discretization techniques are d e m o n s t r a t e d using two oned i m e n s i o n a l and four two-dimensional test problems. These problems d e m o n s t r a t e the accuracy and susceptibility to ray effects of the proposed methods. C o m p a r i s o n s of all calculations are m a d e with the conventional SN and PN approximations. B e n c h m a r k solutions are provided by the established code EVENT.
06/00922 Mathematical study of two controlled convertertype utility interface for harmonic attenuation Kwak, S. and Toliyat, H. A. Electric Power Systems Research, 2005, 75, (2 37, 124 133. Diode rectifiers are very popular in industry from a few k W to a few h u n d r e d s of kW. Two methods based on controlled converter-type utility interface are possible for harmonic-pollution problems caused by the diode rectifiers: one replacing the diode rectifier with a P W M rectifier and the other connecting an active power filter to the diode rectifier. Despite n u m e r o u s publications for the two converters, the features and evaluations between them have not been clearly explained. This paper, in detail, presents theoretical analyses and systematic comparisons of the two converters, from the point of view of converter k V A ratings, dc bus voltage requirements, switch ratings, and reactive c o m p o n e n t designs.
06/00923 Mathematical theory of dimensioning and parameterising product geometry Srinivasan, V. International Journal of Product Lifecycle 3lanagement, 2005, 1, (17, 70 85. The classic art of d i m e n s i o n i n g a drawing and the m o d e r n art of p a r a m e t e r i s i n g a product geometric m o d e l in a computer aided system have a lot in common. As industry moved into the information age, this commonality b e c a m e a p p a r e n t and the need to find a unified m a t h e m a t i c a l theory assumed greater urgency. This paper presents the results of nearly two decades of work towards such a theory. It is based exclusively on congruence theorems, some of which are known since the days of Euclid and others which were proved only recently. These results are being incorporated into national and i n t e r n a t i o n a l standards that deal with product lifecycle m a n a g e m e n t .
06/00924 Measurement and prediction of vapour pressures of 2,6,10,14-tetramethylpentadecane (pristane), Experimental and Monte Carlo simulation results Bourasseau, E. et al. Fluid Phase Equilibria, 2005, 225, 49 57. This work presents results obtained in the characterization of a long branched alkane, the 2,6,10,14-tetramethylpentadecane (pristane), by establishing v a p o u r pressures following two ways of investigation. First, an e x p e r i m e n t a l study has been done in order to perform measure-
06/00916 Effects of the Laurent and Taylor expansions on the calculations of the thermal neutrons inelastic scattering cross sections for crystalline moderators Difilippo, F. C. and Renier, J. P. Annals of Nuclear Energy, 2005, 32, (127, 1323 1336. The use of updated p h o n o n spectra for the calculation of the scattering matrix, S(c~,/3,T7, of graphite made a p p a r e n t discrepancies more related to numerical artifacts than to genuine differences. C o m p a r i n g results from the use of the codes G A S K E T and L E A P R , with improved p h o n o n spectra, the authors found consistent results only when a consistent a s y m p t o t i c region a r o u n d zero frequency is used. This effect is produced by a second order pole at frequency zero that appears during the calculation of S(c~,/3,T7 via a double Fourier transform. The pole also affects the q u a d r a t u r e s at higher frequencies so it became n a t u r a l to use the Laurent expansion rather than Taylor's for a more robust numerical method. The results of this analysis were included in the local version of the codes G A S K E T and L E A P R .
06/00917 Effects of viscous dissipation on the heat transfer in a forced pipe flow, Part 2: Thermally developing flow Aydin, O. Energy Conversion and Management, 2005, 46, (18 197, 3091 3102. In this part of the study, consideration is given to thermally developing laminar forced convection in a pipe including viscous dissipation. The axial heat conduction in the fluid is neglected. Two different t h e r m a l b o u n d a r y conditions are considered: the constant heat flux (CHF) and the constant wall t e m p e r a t u r e (CWT). Both the wall heating (the fluid is heated) case and the wall cooling (the fluid is cooled) case are considered. The distributions for the developing t e m p e r a t u r e and local Nusselt n u m b e r in the entrance region are obtained. Results show that the t e m p e r a t u r e profiles and local Nusselt n u m b e r are influenced by the B r i n k m a n n u m b e r (Br7 and the thermal b o u n d a r y condition used for the wall. Significant viscous dissipation effects have been observed for large Br.
06/00918 Experimental and numerical study of threedimensional flow field in mini-environment Cheng, C.-S. and Hung, J.-S. Energy and Buildings, 2005, 37, (67, 579 586. This study is concerned with t h r e e - d i m e n s i o n a l air flow field for improving the ventilation performance of a m i n i - e n v i r o n m e n t in which toxic gas is produced during the coating process. To investigate the air flow field, m e a s u r e m e n t for the velocity distribution has been m a d e by using a t h r e e - d i m e n s i o n a l ultrasonic a n e m o m e t e r , and n u m e r i c a l simulation using c o m p u t a t i o n a l fluid dynamics (CFD) analysis tool has also been performed. Results of the numerical simulation based on the R N G k c turbulence model are confirmed by the experiments, and modifications in geometric configuration of the system are investigated. It is found that the numerical and experimental approaches used in this study lead to useful i n f o r m a t i o n of flow field and the ventilation performance in the mini-environment may be greatly improved by adjusting the location of the H E P A and modifying the shape of the inlet of the exhaust pipe.
06/00919 Identification and properties of the fundamental expansion functions for neutron transport in an infinite homogeneous medium Milgram, M. S. Annals of Nuclear Energy, 2005, 32, (11), 1167 1190. Starting from the basic expression for the neutron flux due to a point source in an infinite h o m o g e n e o u s scattering and absorbing medium, the first few f u n d a m e n t a l expansion functions corresponding to successive collisions are identified, and their analytic properties are presented, in spherical and plane geometry. Various representations of
134
Fuel and Energy Abstracts
March 2006
the functions are obtained in the form of power series, an expansion in a series of exponential integrals, and other integrals. The adequacy of traditional asymptotic forms is considered.
06/00920 Inverter topologies for DSTATCOM applications a simulation study Iyer, S. et al. Electric Power Systems Research, 2005, 75, (2 37, 161 170. This paper describes a few different topologies of inverters used for realizing a distribution static c o m p e n s a t o r ( D S T A T C O M ) . A brief introduction of the need for s h u n t c o m p e n s a t i o n as well as the r e q u i r e m e n t s of the shunt c o m p e n s a t o r has also been given. A n algorithm for generating references has been described. Three major topologies of inverters three-leg inverter with single dc capacitor, three-leg inverter with neutral clamped dc capacitors, four-leg inverter and three single-phase inverters with c o m m o n dc capacitor have been described and simulated. D S T A T C O M topologies for high voltage distribution systems have also been described. The voltage source converter (VSC) topologies have been c o m p a r e d on the basis of the performance of the inverter for certain chosen system conditions and the n u m b e r of switch devices and dc capacitors used. All simulations have been performed using P S C A D / E M T D C .
06/00921 Linear and quadratic octahedral wavelets on the sphere for angular discretisations of the Boltzmann transport equation Buchan, A. G. et al. Annals of Nuclear Energy, 2005, 32, (117, 1224 1273. In this paper, two new wavelet bases are developed for discretizing the angular term of the first-order Boltzmann t r a n s p o r t equation. The wavelets proposed are based on Swelden's second-generation wavelets, which are constructed through the lifting procedure. In this paper, the wavelets are built on an octahedral d o m a i n and the angular flux approximation takes the form of finite e l e m e n t linear and quadratic representations. Full details of the meshing over the o c t a h e d r o n and derivation of the wavelet functions are given. The wavelets discussed are similar to the wavelets developed in the earlier studies where the bases use a new f u n d a m e n t a l a m e n d m e n t for mitigating the inaccuracies observed with the earlier bases. The performance of the new angular discretization techniques are d e m o n s t r a t e d using two oned i m e n s i o n a l and four two-dimensional test problems. These problems d e m o n s t r a t e the accuracy and susceptibility to ray effects of the proposed methods. C o m p a r i s o n s of all calculations are m a d e with the conventional SN and PN approximations. B e n c h m a r k solutions are provided by the established code EVENT.
06/00922 Mathematical study of two controlled convertertype utility interface for harmonic attenuation Kwak, S. and Toliyat, H. A. Electric Power Systems Research, 2005, 75, (2 37, 124 133. Diode rectifiers are very popular in industry from a few k W to a few h u n d r e d s of kW. Two methods based on controlled converter-type utility interface are possible for harmonic-pollution problems caused by the diode rectifiers: one replacing the diode rectifier with a P W M rectifier and the other connecting an active power filter to the diode rectifier. Despite n u m e r o u s publications for the two converters, the features and evaluations between them have not been clearly explained. This paper, in detail, presents theoretical analyses and systematic comparisons of the two converters, from the point of view of converter k V A ratings, dc bus voltage requirements, switch ratings, and reactive c o m p o n e n t designs.
06/00923 Mathematical theory of dimensioning and parameterising product geometry Srinivasan, V. International Journal of Product Lifecycle 3lanagement, 2005, 1, (17, 70 85. The classic art of d i m e n s i o n i n g a drawing and the m o d e r n art of p a r a m e t e r i s i n g a product geometric m o d e l in a computer aided system have a lot in common. As industry moved into the information age, this commonality b e c a m e a p p a r e n t and the need to find a unified m a t h e m a t i c a l theory assumed greater urgency. This paper presents the results of nearly two decades of work towards such a theory. It is based exclusively on congruence theorems, some of which are known since the days of Euclid and others which were proved only recently. These results are being incorporated into national and i n t e r n a t i o n a l standards that deal with product lifecycle m a n a g e m e n t .
06/00924 Measurement and prediction of vapour pressures of 2,6,10,14-tetramethylpentadecane (pristane), Experimental and Monte Carlo simulation results Bourasseau, E. et al. Fluid Phase Equilibria, 2005, 225, 49 57. This work presents results obtained in the characterization of a long branched alkane, the 2,6,10,14-tetramethylpentadecane (pristane), by establishing v a p o u r pressures following two ways of investigation. First, an e x p e r i m e n t a l study has been done in order to perform measure-