The impact on the heat exchanger performance due to maldistribution of evaporating CO2 in parallel channels is investigated numerically. A 1D steady state simulation model of a microchannel evaporator is built using correlations from the literature to calculate frictional pressure drop and heat transfer coefficients. For two channels in parallel two different cases of maldistribution are studied. Firstly, the impact of a non-uniform air flow is considered, and secondly the impact of maldistribution of the two phases in the inlet manifold is investigated. The results for both cases are compared to results obtained using R134a as refrigerant, and it is found that the performance of the evaporator using CO2 is less affected by the maldistribution than the evaporator using R134a as refrigerant. For both cases studied, the impact of the maldistribution was very small for CO2.
|Title of host publication||Proceedings of 8th IIR Gustav Lorentzen Conference on Natural Working Fluids|
|Editors||Svenn Hansen, Joachim Paul|
|Publication status||Published - 2008|
|Event||8th IIR Gustav Lorentzen Conference on Natural Working Fluids - Copenhagen|
Duration: 1 Jan 2008 → …
|Conference||8th IIR Gustav Lorentzen Conference on Natural Working Fluids|
|Period||01/01/2008 → …|