Fouling detection in a shell and tube heat exchanger using variation of its thermal impulse responses: Methodological approach and numerical verification

Transient detection of either maldistribution or flowrate change in a counter current plate-fin heat exchanger using an ARX model

“…In particular, they apply to short heat exchangers of high conductivities when conjugate heat transfer may appear [14], in particular for short length heat exchangers with millimetric or sub-millimetric channels. These models are very general and can be used a priori for NDT of any type of exchanger, see [19] for example, provided that there is no phase change. Its possible application to exchangers with compressible fluids remains to be studied and tested.…”

“…We have shown, on a numerical basis, how fouling can be detected in a shell and tube heat exchanger [19] using identification of its impulse responses. This corresponds to the reduction of a detailed numerical model where the transient temperature field is modeled in the fluid and solid without any need for correlations for the local heat transfer coefficient.…”

Evaluation of Crude Oil Fouling Formation in a Heat Exchanger with Twisted Tape Inserts

“…Different methods have been studied to evaluate the problem of fouling inside heat exchangers. Significant results were obtained by Al Hadad et al, who applied a method based on the sensitivity of the impulse response (temporal version of the transfer function) to the system [7]. This method is based on the variation of the impulse response that characterizes the system (thermal signature) with fouling.…”