Investigation of gas-solids flow hydrodynamics in a cold model of a dual fluidised bed gasifier using electrical capacitance tomography sensors

The flow characteristics of a dual fluidised bed gasifier(DFBG)are more complex than those of a single fluidised bed gasifier.For stable operation and appropriate control,a cold DFBG test facility with both an upper and a lower U-valve was built,and electrical capacitance tomography(ECT)sensors were installed with pressure transducers to investigate the effects of operating conditions on gas-solids flow hydrodynamics.The operating parameters included gas velocities in the riser and in the bubbling fluidised bed,aeration velocity in the lower U-valve,bed material inventory,and particle size.This is the first time that ECT was applied in different flow zones of a dual fluidised bed gasifier system.The experimental results indicated that ECT in the recycle chamber could monitor the performance of the lower U-valve under different operating conditions for early detection of gas shortcut from the riser to the bubbling bed.Three main flow regimes in the riser and the differences between the reactors were identified by two sets of ECT sensors with pressure transducers.Finally,the effects of the operating conditions on the pressure drop in different parts of the DFBG was investigated.

Embodied tactile perception and learning

Various living creatures exhibit embodiment intelligence,which is reflected by a collaborative interaction of the brain,body,and environment.The actual behavior of embodiment intelligence is generated by a continuous and dynamic interaction between a subject and the environment through information perception and physical manipulation.The physical interaction between a robot and the environment is the basis for realizing embodied perception and learning.Tactile information plays a critical role in this physical interaction process.It can be used to ensure safety,stability,and compliance,and can provide unique information that is difficult to capture using other perception modalities.However,due to the limitations of existing sensors and perception and learning methods,the development of robotic tactile research lags significantly behind other sensing modalities,such as vision and hearing,thereby seriously restricting the development of robotic embodiment intelligence.This paper presents the current challenges related to robotic tactile embodiment intelligence and reviews the theory and methods of robotic embodied tactile intelligence.Tactile perception and learning methods for embodiment intelligence can be designed based on the development of new large-scale tactile array sensing devices,with the aim to make breakthroughs in the neuromorphic computing technology of tactile intelligence.