Heat Transfer Experiments on a Pulse Detonation Driven Combustor

摘要

Heat transfer experiments were conducted using a heat exchanger behind a pulse detonation combustor and a Garrett automotive turbocharger at the Air Force Research Lab (AFRL). The equivalence ratio and purge fraction were held at 1.0 and 0.9, respectively, while the frequency of operation was varied from 10 to 12 Hz in 1 Hz movements, and the fill fraction was varied from 0.5 to 0.8 in 0.1 increments. Temperature measurements were calculated using an energy balance allowing for the calculation of heat exchanger inlet enthalpy. The heat exchanger inlet enthalpy was estimated to be the exit enthalpy of the turbocharger it was coupled to. The representative turbine inlet enthalpy was calculated using compressor work and radiation from the turbine. Turbine inlet and exit temperatures were also measured directly using J-type and K-type thermocouples and compared to calculated values using the heat exchanger approach. Turbine work was calculated from the change in enthalpy from the inlet to the exit. This data was compared with average values of time accurate data from published work. Compressor and turbine work was also presented and compared with recently attained values. Efficiency was presented for varying pressure ratios. The efficiency measurements were compared with time accurate efficiency measurements from on-going work.