Thermodynamic Modeling of a Rotating Detonation Engine (original) (raw)

Thermodynamic model of a rotating detonation engine

Combustion, Explosion, and Shock Waves, 2014

The conventional Zel'dovich-von Neumann-Döring (ZND) detonation theory is modified with two-dimensional velocity vectors to account for the performance and steady-state flow features of a rotating detonation engine. The developed analytical model explains many of the steady-state features of the rotating detonation and its thermodynamics. The generation of swirl is shown to be the primary mechanism of energy transfer.

Numerical Investigation of Rotating Detonation Engine Propulsive Performance

Combustion Science and Technology, 2010

Rotating detonation engines are widely studied because of their compact configurations and high thermal cycle efficiency. For briefty, most of the numerical simulations of rotating detonation engines used premixed reactant mixtures. The rotating detonation waves under non-premixed condition are not studied enough. Here, a series of three-dimensional numerical simulations of a rotating detonation engine under both premixed and non-premixed conditions using H 2 /air mixture are performed. The explicit formulation of density-based solver in ANSYS Fluent is used to perform the simulations. Two total mass flow rates of 272.3 g/s and 500 g/s are selected. When the total mass flow rate is 272.3 g/s, the engine operates at single-wave mode under both premixed and non-premixed conditions. When the total mass flow rate is 500 g/s, the engine operates at single-wave mode under premixed condition. While under non-premixed condition, a spontaneous formation of dual-wave mode is observed. This case agrees well with the phenomenon observed in experiments that as the total mass flow rate increases, the number of rotating detonation waves tends to increase. Pressure waves caused by the high pressure behind the detonation waves can propagate upstream to the H 2 and air plenums.

Three-dimensional modeling of the Rotating Detonation Engine

A continuously rotating detonation was firstly reported in the early sixties of the last century by Voitsekhovskii et al. But only recently a significant interest has been focused on development of the Rotating Detonation Engine, known also as Continuous Detonation Wave Engine, since it offers significant improvements of the cycle efficiency and simultaneous simplification of the design. Many experimental and numerical investigations in this field are conducted in many laboratories [2-4]. Despite many successful experiments into establishing of rotating detonation in different chamber’s geometries and for different mixture compositions there is still a great need for a numerical simulation which can provide detailed data about the flow’s structure and allows better understanding of the ongoing processes. The work presents the results of three-dimensional simulations of a detonation propagating in continuously flowing gas. The simulations show the large scale structure of the detonat...

Role of inlet reactant mixedness on the thermodynamic performance of a rotating detonation engine

Shock Waves, 2015

Rotating Detonation Engines have the potential to achieve the high propulsive efficiencies of detonation cycles in a simple and effective annular geometry. A twodimensional Euler simulation is modified to include mixing factors to simulate the imperfect mixing of injected reactant streams. Contrary to expectations, mixing is shown to have a minimal impact on performance. Oblique detonation waves are shown to increase local stream thermal efficiency, which compensates for other losses in the flow stream. The degree of reactant mixing is, however, a factor Communicated by J. Yang.

THREE-DIMENSIONAL NUMERICAL SIMULATIONS OF THE COMBUSTION CHAMBER OF THE ROTATING DETONATION ENGINE

Journal of KONES. Powertrain and Transport, 2013

From 2010 Warsaw University of Technology (WUT) and Institute of Aviation (IoA) jointly implement the project under the Innovative Economy Operational Programme entitled 'Turbine engine with detonation combustion chamber'. The goal of the project is to replace the combustion chamber of turboshaft engine GTD-350 with an annular detonation chamber. During the project, the numerical group that aims to develop computer code allowing researchers to simulate investigated processes has been established. Simulations provide wide range of parameters that are hardly available from experimental results and enable better understanding of investigated processes. Simulations may be also considered as a cheap alternative for experiments, especially when testing geometrical optimizations.

Analysis of the actual thermodynamic cycle of the detonation engine

Applied Thermal Engineering, 2016

Two variants of the limitations are analysed: in the first case the cycles are compared at the same degree of adiabatic compression, in the secondwithin the same interval of limiting temperatures. The values of the thermal efficiency and pressure intervals are compared, as well as the introduced additional criteria for assessing the thermodynamic perfection: the specific volume work, the criterion of irreversibility, and the nondimensional value Z, characterizing the fraction of the effective work from the mechanical work obtained per cycle. The analysis carried out has revealed that a detonation engine possesses an advantage over some parameters, especially over the thermal efficiency, but its superiority is not absolute.

Computation of Thermodynamic Cycle for Novel Detonation Aircraft Engine

2015

The paper presents the thermodynamic cycle for a novel detonation based, aircraft engine. First, an overview of the existing models is presented, introducing the most common detonation models in the literature: the Humphrey cycle, the Zeldovitch Neumann van Doring cycle, and the Fickett Jacobs cycle. Algorithms for determining the thermodynamic cycles for the selected three detonation models are presented, and numerical results for a case study involving a detonation based, aircraft engine are provided. Finally, the theoretical cycle efficiency, the useful work and the cycle specific heat for the studied engine are also determined.

Experimental validation of rotating detonation for rocket propulsion

Scientific Reports

Space travel requires high-powered, efficient rocket propulsion systems for controllable launch vehicles and safe planetary entry. Interplanetary travel will rely on energy-dense propellants to produce thrust via combustion as the heat generation process to convert chemical to thermal energy. In propulsion devices, combustion can occur through deflagration or detonation, each having vastly different characteristics. Deflagration is subsonic burning at effectively constant pressure and is the main means of thermal energy generation in modern rockets. Alternatively, detonation is a supersonic combustion-driven shock offering several advantages. Detonations entail compact heat release zones at elevated local pressure and temperature. Specifically, rotating detonation rocket engines (RDREs) use detonation as the primary means of energy conversion, producing more useful available work compared to equivalent deflagration-based devices; detonation-based combustion is poised to radically im...

Detonation Engine Performance Comparison Using First and Second Law Analyses

46th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, 2010

A performance comparison between airbreathing pulsed detonation engine (PDE) and rotating detonation wave engine (RDWE) concepts is made. The flight speed range used for the analysis is approximately Mach 1-5, which is typically thought to be where these concepts are viable and perhaps competitive with each other and Brayton cycle engines. Since the RDWE is ideally capable of operation with a steady state inlet and nozzle, a PDE model with similar steady state systems was developed. The comparison shows a PDE is more efficient at low supersonic speeds, but the relative RDWE performance gradually increases until it becomes comparable. The thermodynamic cycles of these detonationbased engines have been examined in detail using the Second Law to show the losses associated with mixing and purging. Additionally, the combination of an exergy analysis with First Law performance benchmarks proves to be a useful approach for optimization since sources of losses and component interrelationships are easier to identify.