TOTAL TEMPERATURE MEASUREMENT AT PULSE DETONATION ENGINE EXHAUST

Abstract

Pulse detonation engines (PDEs) are being studied in recent years as a potential means of power production. In PDEs, a supersonically travelling detonation wave traverses through the detonation tube. Total temperature of the exhaust of the PDE is not a well-known parameter. The objective of the research was to calibrate and employ miniature type E thermocouples for exhaust temperature measurement of the PDE. The probe making process along with the calibration techniques for AWG 20, AWG 24 and AWG 50 thermocouples are discussed at length. The time constants for thermocouples were determined. Reactive mixture containing hydrogen and oxygen was used in the pulse detonation engine. The exhaust pressure was also measured. The exhaust temperature recorded to be vastly different from theoretical predictions. It is hypothesized that radiation losses are the major reason for cooling of jet plume causing the drop in temperature. A shielded enclosure for exhaust temperature measurement to mitigate the losses is recommended.