To establish empirical correlations and develop numerical codes for optimising the design of heat exchangers operating in freeboard regions of fluidised bed reactors. The correlations and the codes will enable designers of cross flow tubular heat exchangers to choose the array geometry which would yield optimal heat transfer for a particular operational environment.
The work will be conducted jointly by Trinity College, Dublin and Intron BV, Netherlands and will cover the following phases:
1) Local Heat Transfer Measurements.
An existing facility for local and overall heat transfer measurements will be used to examine the effects of finer particles as recent work has indicated that the greatest enhancement of heat transfer is achieved with small particles. In order to verify correlations developed from preliminary studies, a greater range of flow rates, typical of fluidised bed combustors, will be examined. In addition, the effect of varying the tube array lay-out and geometry and the influence of particle properties will be investigated.
2) Laser Anemometry Measurements.
A single channel LDA system will be used to examine the effect of particles on both velocity and turbulence characteristics in the boundary layer and through flow regions for a single cylinder and a tube array. The data will be used to provide a fundamental understanding of the heat transfer measurements and as validation for the numerical codes.
3) Numerical Analysis.
Numerical procedures are to developed for the prediction of heat transfer in gas/particle flows. The core of the predictions will be the tracking of particle trajectories such that correlations based on local particle concentrations and residence times can be implemented and the influence of the particles on the flow and turbulence characteristics of the carrier phase.
Funding SchemeCSC - Cost-sharing contracts
6130 PD Sittard