Review paper of two-phase flow boiling pressure drop in propane refrigeration system

This paper is about paper or journal review of two-phase flow boiling pressure drop in propane (R290) refrigeration system and summarized several researches that will useful in terms of HVAC-R equipment especially in heat exchanger i.e., evaporator design. Early researcher has been conducted research with respect to the channel dimension (diameter and aspect ratio) as in Coleman (2000). Recent research of flow boiling with combined parameters such as heat transfer coefficient (HTC) and pressure drop shown that some parameters affected pressure drop inside unconventional channel (mini and microchannel) such as superficial vapor velocity, mass quality, mass flux, heat flux, saturation temperature (and pressure), and Reynolds number where flow regime of the pressure drop are mostly annular flow, intermittent flow, slug and churn flow but less or few of them found a relation of channel dimension i.e. diameter and aspect ratio towards two-phase flow pressure drop (as in Coleman (2000)). It is recommended that for further study and research, study of two-phase flow boiling pressure drop must conduct in the unconventional channel such as minichannel or microchannel i.e., capillary tube and incorporate Reynolds number of the flow (both vapor and liquid), channel dimension (diameter and aspect ratio), surface tension, and shear stress influence from two-phase flow fluid and then plot the data to the recent and or existed flow pattern map of any flow regimes especially to the refrigerants ones.