Experimental measurements of the thermal conductivity of ash deposits: Part 1. Measurement technique

Robinson, A. L. ; Buckley, S. G. ; Yang, N. ; Baxter, L. L.

Sandia National Laboratories

关键词: Boilers;    On-Line Measurement Systems;    Thermal Conductivity;    01 Coal, Lignite, And Peat;    Ashes;   

DOI  :  10.2172/755936
RP-ID  :  SAND2000-8599
RP-ID  :  AC04-94AL85000
RP-ID  :  755936

美国|英语

来源: UNT Digital Library

【 摘 要 】

This paper describes a technique developed to make in situ, time-resolved measurements of the effective thermal conductivity of ash deposits formed under conditions that closely replicate those found in the convective pass of a commercial boiler. Since ash deposit thermal conductivity is thought to be strongly dependent on deposit microstructure, the technique is designed to minimize the disturbance of the natural deposit microstructure. Traditional techniques for measuring deposit thermal conductivity generally do not preserve the sample microstructure. Experiments are described that demonstrate the technique, quantify experimental uncertainty, and determine the thermal conductivity of highly porous, unsintered deposits. The average measured conductivity of loose, unsintered deposits is 0.14 {+-} 0.03 W/(m K), approximately midway between rational theoretical limits for deposit thermal conductivity.