Abstract

In this paper tube-in-tube heat exchangers are discussed in which heat is transferred from a nanofluid to water. The nanofluids considered are stable suspensions of graphene nanoplatelets in water. The properties of such nanofluids are experimentally known with its corresponding inherent uncertainty associated. The main purpose of this work is to find out how this uncertainty affects the uncertainty of heat exchanger performance estimators, such as Nusselt number, convective heat transfer coefficient, pressure drop, etc. For this purpose, we use the Stochastic Collocation Method in combination with an empirical Anzats to evaluate the heat exchanger performance. The results show that the uncertainty in knowing the density of the nanofluid does not affect the result significantly. However, the uncertainty arising from the ignorance of thermal conductivity, viscosity and specific heat is not negligible.