Interior Ballistics Two-Phase Reactive Flow Model Applied to Small Caliber Projectile-Gun System

2015 ◽  
Vol 40 (5) ◽  
pp. 720-728 ◽  
Author(s):  
Ahmed Bougamra ◽  
Huilin Lu
2013 ◽  
Vol 80 (3) ◽  
Author(s):  
Changjun Ma ◽  
Xiaobing Zhang

The modular charge is developed to replace the conventional bagged charge systems for many advantages. In the interior ballistic cycle of a modular charge system, the nonsimultaneous ignition of propellant in different cases results in an increasing pressure wave, and can cause a launch safety problem of the gun. Because the charge structure is complicated, it is hard to simulate the interior ballistics process for the modular charge system currently. To simulate the interior ballistic of the modular charge system more accurately, an improved interior ballistic one-dimensional two phase flow model for modular charge system is established. The improvement of this model lies in that it takes account of the discontinuity of the propelling charge bed, the block of the cartridge wall to the flame spreading in propelling charge bed, effects of modular cartridge movement to the interior ballistic performance, the nonsimultaneous breakup of the modular charge cartridges, the ignition of the propelling charge in different cartridges, and flame spreading through the cap of the core tubes. Simulation for a full charge and three lower charge cases with different charge position were carried out based on the model. The simulation results proved that the model is reliable, and can be used to study the effects of cartridge mechanical properties, charge position, different charge zones on interior ballistic performance of modular charges.


2013 ◽  
Vol 465-466 ◽  
pp. 592-596
Author(s):  
Mahmoud M. Rashad ◽  
Xiao Bing Zhang ◽  
Hazem El Sadek ◽  
Cheng Cheng

The two-phase flow mathematical model for the solid granular propellant and its products of combustion inside large caliber naval gun guided projectile system (NGGPS) during interior ballistic cycle is presented. The model includes the governing equations of mass, momentum and energy for both phases as well as the constitutive laws. The discharged combustion products from the igniter vent-holes into the chamber are acquired by incorporation in the model the two-phase flow model of the bayonet igniter. The system of equations of the two-phase flow model is solved using the second order accurate Maccromacks technique. A one dimensional model introduced by G.A. Sod (shock tube) is utilized to test the ability of Maccromacks algorithm in solving the initial boundary value problem (IBVP) for the system of equations with shock wave behavior. The numerical method is verified by using an exact solution of a test problem. The moving control volume conservation method (MCVC) is used to handle the moving boundary as well as a self-adapting method was used to expand the computational domain in order to follow the movement of the projectile down the gun bore. The numerical results are validated with experimental data. The interior ballistics performance of a 130 mm naval guided projectile gun system is closely predicted using the presented two-phase flow model and the numerical code.


2015 ◽  
Vol 25 (9) ◽  
pp. 795-817 ◽  
Author(s):  
Mika P. Jarvinen ◽  
A. E. P. Kankkunen ◽  
R. Virtanen ◽  
P. H. Miikkulainen ◽  
V. P. Heikkila

2004 ◽  
Author(s):  
Gary Luke ◽  
Mark Eagar ◽  
Michael Sears ◽  
Scott Felt ◽  
Bob Prozan

Micromachines ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 510
Author(s):  
Yan Huang ◽  
Bifen Shu ◽  
Shengnan Zhou ◽  
Qi Shi

In this paper, two-phase pressure drop data were obtained for boiling in horizontal rectangular microchannels with a hydraulic diameter of 0.55 mm for R-134a over mass velocities from 790 to 1122, heat fluxes from 0 to 31.08 kW/m2 and vapor qualities from 0 to 0.25. The experimental results show that the Chisholm parameter in the separated flow model relies heavily on the vapor quality, especially in the low vapor quality region (from 0 to 0.1), where the two-phase flow pattern is mainly bubbly and slug flow. Then, the measured pressure drop data are compared with those from six separated flow models. Based on the comparison result, the superficial gas flux is introduced in this paper to consider the comprehensive influence of mass velocity and vapor quality on two-phase flow pressure drop, and a new equation for the Chisholm parameter in the separated flow model is proposed as a function of the superficial gas flux . The mean absolute error (MAE ) of the new flow correlation is 16.82%, which is significantly lower than the other correlations. Moreover, the applicability of the new expression has been verified by the experimental data in other literatures.


Energy ◽  
2021 ◽  
Vol 218 ◽  
pp. 119543
Author(s):  
Jingxian Chen ◽  
Peihang Xu ◽  
Jie Lu ◽  
Tiancheng Ouyang ◽  
Chunlan Mo

Sign in / Sign up

Export Citation Format

Share Document