Experimental Study on an Opposite Firing Boiler Slagging Mechanism in and the Countermeasures

Cold tests and numerical simulation were conducted to study the causes leading to slagging in an opposite firing boiler with swirl burners, which was found to be formed mainly in the area surrounding the burners through site and macro-morphology inspection, and was subsequently found to be caused by outlet airflow divergence through cold tests. Simulation […]

Optimization of UAV Wing Bionic Airfoil Profile Design Based on Orthogonal Experiment

In view of the design of unmanned aerial vehicle(UAV)airfoil profile,using bionic method,the airfoil profile is intercepted from the wing of seagull,which is the biological prototype,and the orthogonal test optimization is done on the obtained original airfoil profile.The results show that,the thickness of the rear of airfoil profile has the greatest impact on the lift-drag ratio […]

Two-dimensional Interior Ballistics Model of High Pressure Ejection Apparatus and Analysis on the Characteristics of Flow Field in Launching Chamber

High pressure accumulated by propellant burning in high pressure ejecting apparatus makes the chamber open instantly and eject a projectile to a target. In order to grasp the complex change of gas flow in the launching chamber,a two-dimensional interior ballistics model is established and simulated by Runger-Kutta and Mac Cormark schemes. The calculated pressure results […]

Study on fracture of cartridge case in ironing process

For problems of the cup shell crack for cartridge case in the ironing process,a theory model of stress calculation for multi-mode ironing process was derived from the classical theory of ironing with a single die,and the simulation on multi-mode ironing process was carried out by Deform.Therefore,the influencing parameters and the curve of stress change at […]

Reduction of global effects on vehicles after IED detonations

Global effects caused by the detonation of an IED near a military vehicle induce subsequent severe acceleration effects on the vehicle occupants. Two concepts to minimize these global effects were developed, with the help of a combined method based on a scaled experimental technology and numerical simulations. The first concept consists in the optimization of […]

Simulating cavitation erosion of cylinder liner caused by wall vibration

To study the cylinder wall vibration cased by the knocking piston to cylinder liner cavitation which is near the cooling water flow field by wall vibration, using computational fluid dynamics (CFD) method, based on Eulerian multiphase cavitation models provided by AVL – Fire computational fluid software, combined with the dynamic mesh technology to build multiphase […]

Experiment and Numerical Simulation Research on Measuring the Detonation Pressure of Industrial Detonator

In order to quantitatively evaluate the output power of industrial detonator,a combination of experiment andnumerical simulation method was used to get the detonation pressure of industrial detonator.In view of the signal interference inthe process of testing,the test system has been improved so as to get clear curves of the measurement.The commercial softwareAUTODYN was employed to […]

Supporting design and optimization of large section roadway with straight wall and semicircle arch

Aiming at the problem of supporting difficulties and serious deformation in large section roadway, took the 2nd rail roadway in Xinyu mine as engineering background, the method of theoretical calculation combined with numerical simulation are adopted to analyze characteristics of deformation and damage in roadway surrounding rock, the stress state and plastic zone distribution are […]

Numerical Simulation of Fast Cook-off Characteristics for Base Bleeding Propellant

To investigate the thermal safety of the base bleeding projectile, based on the two-step chemical reaction mechanism of ammonium perchlorate(AP)/hydroxyl-terminated polybutadiene(HTPB) base bleeding propellant, a two-dimensional unsteady state cook-off model of the base bleeding unit is built. The fast cook-off response characteristics of the base bleeding unit were analyzed under the conditions of the external […]

Numerical Simulation of Prefabricated Fragment/MEFP Combat Warhead

A new type of combined warhead structure,which can form prefabricated fragments and MEFP,is used to simulate the forming process of ANSYS/LS-DYNA software. The simulation results show that the new prefabricated fritters/MEFP combined warheads can form multiple damage elements with high speed,large quantity and large killing area. MEFP Damage Element has the characteristics of deep perforation […]