Experimental investigation on multi-cycle two-phase spiral pulse detonation tube of two configurations

2018 ◽  
Vol 233 (11) ◽  
pp. 4166-4175
Author(s):  
Hua Qiu ◽  
Zheng Su ◽  
Cha Xiong
Keyword(s):  
Pressure Waves ◽  
Propagation Characteristics ◽  
Transient Pressure ◽  
Two Phase ◽  
Pulse Detonation ◽  
Compression Waves ◽  
Detonation Tube ◽  
Deflagration To Detonation Transition ◽  
Pulsed Detonation ◽  
Detonation Transition

The spiral tube structure is an effective method to shorten the axial length of the pulse detonation chamber. In this article, spiral pulsed detonation tube with two kinds of spiral configuration was experimentally investigated. Liquid gasoline and air were used as fuel and oxidant, respectively, and equivalence ratios were controlled to about 1.0. Based on the transient pressure along the tube, the propagation characteristics of the pressure waves in the multi-cycle spiral pulsed detonation tubes, such as pressure peaks, wave velocities and propagation process, were analyzed. Results showed that propagation of double compression waves was the common feature during the process of deflagration to detonation transition in the presented spiral tubes, and the onset of detonation was initiated by a local explosion in the second compression wave. The deflagration to detonation transition characteristics with detonation initiation and combustion characteristics without initiation in the spiral sections were both related to the dimensionless distance. Propagation characteristics of the pressure waves were influenced by the use of different spiral configuration. And some interesting phenomena were also found.

NUMERICAL SIMULATION OF DEFLAGRATION-TO-DETONATION TRANSITION IN A PULSED DETONATION ENGINE

2020 ◽  
Author(s):  
A. E. Zangiev ◽  
◽  
V. S. Ivanov ◽  
S. M. Frolov ◽  
◽  
...  
Keyword(s):  
Check Valve ◽  
Fuel Mixture ◽  
Minimum Length ◽  
Flame Acceleration ◽  
Pulsed Detonation Engine ◽  
Detonation Tube ◽  
Deflagration To Detonation Transition ◽  
Pulsed Detonation ◽  
Detonation Engine ◽  
Detonation Transition

The air-breathing pulsed detonation engine (PDE) for an aircraft designed for a subsonic flight when operating on the products of pyrolysis of polypropylene was developed using the analytical estimates and parametric multivariant threedimensional (3D) calculations. The PDE consists of an air intake with a check valve, a fuel supply system, a prechamber-jet ignition system, and a combustion chamber with an attached detonation tube. Parametric 3D calculations allowed choosing the best length of the PDE combustor, which provides an efficient mixing of air with fuel, the best way to ignite the mixture (prechamber-jet ignition), the best location of the prechamber, the minimum length of the section with turbulizing obstacles for flame acceleration and deflagration-to-detonation transition (DDT), and the best degree of filling the detonation tube with the fuel mixture to achieve the maximum completeness of combustion.

Computational Study of Deflagration to Detonation Transition in Pulse Detonation Engine Using Shchelkin Spiral

2015 ◽  
Vol 772 ◽  
pp. 136-140 ◽  
Author(s):  
Pinku Debnath ◽  
Krishna Murari Pandey
Keyword(s):  
Combustion Wave ◽  
Computational Study ◽  
Pulse Detonation Engine ◽  
Flame Velocity ◽  
Pulse Detonation ◽  
Detonation Tube ◽  
Deflagration To Detonation Transition ◽  
Contour Plots ◽  
Detonation Engine ◽  
Detonation Transition

Detonation combustion wave is much more energetic combustion process in pulse detonation engine combustion system. Numerous experimental, theoretical and numerical analyses have been studied in pulse detonation engine to implement in practical propulsion system. In this present computational study the simulation was carried out for deflagration flame acceleration and deflagration to detonation transition of hydrogen air combustible mixture inside the detonation tube with and without Shchelkin spiral. A three dimensional computational analysis has been done by finite volume discretization method using ANSYS Fluent 14 CFD commercial software. The LES turbulence model with second order upwind discretization scheme was adopted with standard boundary conditions for unsteady combustion wave simulations. From the computational study it was found that intensity of detonation wave velocity and dynamic pressure is higher near to the boundary of Shchelkin spiral in detonation tube. The contour plots comparisons clearly show that deflagration flame accelerates in detonation tube as present of Shchelkin spiral. The contour plots also suggest that deflagration flame velocity and pressure are less in without Shchelkin spiral in detonation tube. The accelerating detonation waves are approximately near about Chapment-Jouguet values in detonation tube with Shchelkin spiral.

DETONABILITY OF FUEL-AIR MIXTURES IN TERMS OF DEFLAGRATION-TO-DETONATION TRANSITION

2020 ◽  
Author(s):  
S. M. FROLOV ◽  
◽  
V. I. ZVEGINTSEV ◽  
I. O. SHAMSHIN ◽  
M. V. KAZACHENKO ◽  
...  
Keyword(s):  
Natural Gas ◽  
Experimental Method ◽  
Pyrolysis Products ◽  
Ethylene Propylene ◽  
Pulse Detonation ◽  
Detonation Tube ◽  
Standard Pulse ◽  
Detonation Transition ◽  
Run Up ◽  
Propane Butane

A new experimental method for evaluating the detonability of fuel-air mixtures (FAMs) based on measuring the deflagration-to-detonation (DDT) run-up distance and/or time in a standard pulse detonation tube is used to rank gaseous premixed and nonpremixed FAMs by their detonability under substantially identical thermodynamic and gasdynamic conditions. In the experiments, FAMs based on hydrogen, acetylene, ethylene, propylene, propane-butane, n-pentane, and natural gas of various compositions, as well as FAMs based on the gaseous pyrolysis products of polyethylene (PE) and polypropylene (PP) are used: from extremely fuel-lean to extremely fuel-rich at normal temperatures and pressures.

scholarly journals Deflagration-to-detonation transition in air mixtures of polypropylene pyrolysis products

2019 ◽  
Vol 488 (2) ◽  
pp. 162-166
Author(s):  
S. M. Frolov ◽  
V. I. Zvegintsev ◽  
V. S. Aksenov ◽  
I. V. Bilera ◽  
M. V. Kazachenko ◽  
...  
Keyword(s):  
Decomposition Temperature ◽  
Stoichiometric Mixture ◽  
Gas Generator ◽  
Pyrolysis Products ◽  
Deflagration To Detonation Transition ◽  
Pulsed Detonation ◽  
Hydrocarbon Gas ◽  
Detonation Transition ◽  
Run Up ◽  
Propane Butane

A new method for determining the detonability of fuel is proposed based on the measured values ​​of the detonation run-up distance and time in the standard pulsed detonation tube (PDT). Granulated polypropylene (GP) was used as a fuel. A test bench with the PDT and a gas generator was designed and manufactured for the preparation of the GP pyrolysis products at a decomposition temperature of up to 800 °C. Experiments on deflagration-to-detonation transition in air mixtures of pyrolysis products of the GP showed that such mixtures exhibit detonability close to that of liquefied hydrocarbon gas (LPG) of the propane-butane automobile brand in a stoichiometric mixture with air under normal conditions.

Sign in / Sign up

Export Citation Format

Share Document