Experiment of specific heat capacity of rigid polyurethane foam at low temperature
1.School of Mechanical and Power Engineering, Dalian Ocean University, Dalian, Liaoning 116023, China; 2.School of Mechanical and Power Engineering, Shanghai Jiao Tong University, Shanghai 200030, China
Abstract:To investigate the influence of heat capacity under low temperatures of transitional and environmental friendly polyurethane foam on thermal insulating equipment design, an adiabatic calorimeter was set up. A series of measures were adopted to decrease the heat leakage to maximum extent. With the calorimeter, the specific heat capacities of PU foams blown with CFC-11, HCFC-141b and HFC-245fa were measured respectively in the temperature range from 60 K to ambient condition. The results show that the specific heat capacities increase with the increasing of temperature. For the same blowing agent, the specific heat capacity increases when the density increases, but the influence extent gets slighter at low temperatures.For the same density, the descending sequence of specific heat capacity of three PU foams is HFC-245fa, HCFC-141b and CFC-11, while the influence of blowing agent is negligible in low temperature range.