Foreword by Hongguang Jin
High-Temperature Gas-cooled Reactor (HTGR) is considered one of the most
promising solutions for Generation IV advanced reactors by researchers in the
nuclear energy field. Extensive studies have been carried out in China, the USA,
Germany, and South Africa, which have promoted the development of pebble-type
HTGR significantly. Among such efforts, Prof. Jiang and his team from Institution
of Nuclear and New Energy Technology (INET) of Tsinghua University in China
have had extraordinary contribution.
Approved as one of the “Major Project”s of National Science and Technology
and based on the forward studies of 10MW high-temperature reactor (HTR-10), the
pebble flow and the heat transfer in the pebble-type HTGR are investigated profoundly. The high-temperature reactor-pebble-bed module (HTR-PM) is under
construction in Shandong Province in China. A great number of findings from prior
studies have been validated in this project, which provided instructive knowledge to
scientists and personnel in the nuclear power industry.
High uniformity and the minimum stagnation of the pebble flow are highly
desired with graphite-coated fuel pebbles in the fuel cycle to prevent overheating at
specific areas when the reactor is in operation. By conducting experimental comparisons of different bed configurations, Prof. Jiang and his group have investigated
the state of the art of the scheme of pebble-bed configuration and identified the bulk
dynamics and phenomena of pebble flows. Based on the work, they have proposed
relevant parameters to analyze the flow pattern and uniformity, and optimized the
Particle Tracking Velocimetry (PTV) method, which has proven to be very effective. According to the experiments and velocity characteristics of the pebble bed, a
correlation time and a new intermittency index are proposed from both macroscopic
and microscopic perspectives to analyze the flow pattern, which has significant
value to future optimization of the pebble flow.
To optimize the efficiency of the pebble flow with substantially more cases,
numerical models and schemes must be established and adopted. In this work, the
Discrete Element Method (DEM), a widely utilized approach, is employed.
The DEM successfully simulates a real-scale three-dimensional pebble-bed reactor
HTR-PM, and it is reasonable to consider that the pebble flow is a mass flow
vii
High-Temperature Gas-cooled Reactor (HTGR) is considered one of the most
promising solutions for Generation IV advanced reactors by researchers in the
nuclear energy field. Extensive studies have been carried out in China, the USA,
Germany, and South Africa, which have promoted the development of pebble-type
HTGR significantly. Among such efforts, Prof. Jiang and his team from Institution
of Nuclear and New Energy Technology (INET) of Tsinghua University in China
have had extraordinary contribution.
Approved as one of the “Major Project”s of National Science and Technology
and based on the forward studies of 10MW high-temperature reactor (HTR-10), the
pebble flow and the heat transfer in the pebble-type HTGR are investigated profoundly. The high-temperature reactor-pebble-bed module (HTR-PM) is under
construction in Shandong Province in China. A great number of findings from prior
studies have been validated in this project, which provided instructive knowledge to
scientists and personnel in the nuclear power industry.
High uniformity and the minimum stagnation of the pebble flow are highly
desired with graphite-coated fuel pebbles in the fuel cycle to prevent overheating at
specific areas when the reactor is in operation. By conducting experimental comparisons of different bed configurations, Prof. Jiang and his group have investigated
the state of the art of the scheme of pebble-bed configuration and identified the bulk
dynamics and phenomena of pebble flows. Based on the work, they have proposed
relevant parameters to analyze the flow pattern and uniformity, and optimized the
Particle Tracking Velocimetry (PTV) method, which has proven to be very effective. According to the experiments and velocity characteristics of the pebble bed, a
correlation time and a new intermittency index are proposed from both macroscopic
and microscopic perspectives to analyze the flow pattern, which has significant
value to future optimization of the pebble flow.
To optimize the efficiency of the pebble flow with substantially more cases,
numerical models and schemes must be established and adopted. In this work, the
Discrete Element Method (DEM), a widely utilized approach, is employed.
The DEM successfully simulates a real-scale three-dimensional pebble-bed reactor
HTR-PM, and it is reasonable to consider that the pebble flow is a mass flow
vii