FOULING OF A CYLINDRICAL PROBE AND A FINNED TUBE BUNDLE IN A DIESEL EXHAUST ENVIRONMENT

The objective of this work is to provide data simultaneously from an e xtended surface heat exchanger and a mass accumulation probe in a dies el exhaust environment. To obtain information about the possible link between the fouling behavior of the probe and the heat exchanger, a fi nned tube bundle was inserted in a diesel exhaust gas stream on the DE LFINE loop at GRETh with a mass accumulation probe upstream of the bun dle. A retractable protective device allowed the probe mass accumulati on kinetics to be obtained during each fouling test. The results conce rning the mass accumulation and the heat exchanger (asymptotic) foulin g resistance behavior outline the role of the soot particle thermophor esis and the fluid velocity. The proposed model, which explains the pr obe mass accumulation kinetics, emphasizes the modification of the dep osit thermal conductivity during the deposition. (C) Elsevier Science Inc., 1997.