The potential thermodynamic gain of rotating detonation combustors (RDCs) is typically represented as a pressure gain or increase in total pressure. However, defining a singular total pressure for pressure gain requires averaging due to the unsteady and nonuniform flow. The choice in averaging is nontrivial, and this work details the procedures that conserve the flow’s entropy, thrust output, and work output. These, along with area averaging, are compared to the accepted equivalent available pressure (EAP), with a key finding being that the experimental EAP is equivalent to area averaging. Sample results from three-dimensional direct numerical simulations were analyzed for demonstrative purposes. The experimental EAP was found always to be conservative and underpredicts the other averages by 2.5–38%, with entropy averaging being the most idealistic. This analysis highlights that work averaging is not equivalent to thrust averaging, as the work-averaged total pressures were 4–8% larger. The nonuniqueness in total pressure is exacerbated by the thrust averaging being sensitive to the assumed ambient exit conditions, unlike the work averaging. Overall, this paper highlights that the appropriate averaging procedure depends on the desired RDC application, as the outlet total pressure, needed to define pressure gain, is not intrinsic to the flow after a reduction in dimensionality.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Averaging the Nonuniform Flow in Rotating Detonation Combustors to Determine Gain


    Contributors:

    Published in:

    AIAA Journal ; 63 , 8 ; 3048-3063


    Publication date :

    2025-08-01




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English




    Low-Order Model for Detonation Velocity Suppression in Rotating Detonation Combustors

    Barnouin, Provence / Bach, Eric / Gutmark, Ephraim J. et al. | TIBKAT | 2023


    Low-Order Model for Detonation Velocity Suppression in Rotating Detonation Combustors

    Barnouin, Provence / Bach, Eric / Gutmark, Ephraim J. et al. | AIAA | 2023


    Numerical Investigation of Centerbody-less Rotating Detonation Combustors

    Schwer, Douglas A. / Johnson, Ryan F. / Kercher, Andrew et al. | AIAA | 2020


    NUMERICAL INVESTIGATION OF CENTERBODY-LESS ROTATING DETONATION COMBUSTORS

    Schwer, Douglas A. / Johnson, Ryan F. / Kercher, Andrew et al. | TIBKAT | 2020


    Modeling of liquid injection in rotating detonation combustors

    Suppiah, Alexander / Wang, Robert B. / Paniagua, Guillermo et al. | AIAA | 2024