Dynamic simulation on thermal performance of gas–liquid separated solar collector system with R245fa

A gas–liquid separated solar collector system was developed. The operating temperatures are in the range between 100 and 150 °C. The boiling collector can be used for process heat supply in the industry and for solar cooling applications as well. This gas–liquid separated solar collector system can use flat-plate solar collector and heat pipe solar collector to generate mid-temperature steam. This system can reduce the usage of the heat pipe solar collector and heat the working medium to the saturated liquid by the flat-plate solar collector, which can reduce the cost of the system. R245fa, also known as 1,1,1,3,3-pentafluoropropane, was used as the high temperature working medium in this system. The simulation results show that this system can work normally. When the mass flow of working fluid was reduced by half of general condition, the collection time was cut by 25%. In contrast, when the mass flow of working fluid was kept the same and the collector area was doubled, the operation time was cut by 35%.