Heat Transfer Analysis and Modification of Thermal Probe for Gas-Solid Measurement

Abstract

The presented work aims to measure the gas-solid two-phase mass flow-rate in pneumatic conveyor, and a novel modified thermal probe is applied. A new analysis of the local heat transfer coefficients of thermal probe is presented, while traditional investigations focus on global coefficients. Thermal simulations are performed in Fluent 6.2 and temperature distributions of the probe are presented. The results indicate that the probe has obviously stable and unstable heat transfer areas. Based on understanding of probe characteristics, a modified probe structure is designed, which makes the probe output signal more stable and widens the measuring range. The experiments are carried out in a special designed laboratory scale pneumatic conveyor, and the modified probe shows an unambiguous improvement of the performance compared with the traditional one.

Investigation of Thermal Fields at Phase Boundaries in Powder Mixtures that are Subject to Melting and Chemical Transformation

“…Secondly, in the process of induction heating, the surface of the base metal emits a greater amount of energy (both in the form of heat and in the radiant way) than the formed coating, therefore the pyrometric method of temperature recording is also ineffective and reflects only the thermal state of metal base surface. Thirdly, due to the initial porosity of surfacing material, that is a multicomponent heterogeneous mixture, and porosity which is constantly changing in the IS process, all known contact thermometric methods give obviously irreproducible results [21,22].…”