Soft Recoil Research Articles

Firing Process Modeling of a Soft Recoil Gun Based on Interval Uncertainty Parameter Identification

PurposeThe soft recoil firing technology is an important way to reduce the recoil force of a gun. To further improve the effect of the recoil mechanism and provide a test prediction method for soft recoil firing, a new multi-port structure of the recoil mechanism with a central port and variable depth wall grooves is proposed to research the working characteristics of a soft recoil gun. MethodsTo describe the firing law of a soft recoil gun, this paper establishes its differential equations of firing motion, constructs the analytical model of each subsystem in the system, and acquires a relatively comprehensive way to describe the firing motion process for this soft recoil system. The flow distribution Bernoulli equation is established with CFD fluid simulation to improve the model accuracy. On this basis, the interval uncertainty theory and genetic algorithm are applied to establish the parameter identification model of the firing process. The typical parameters of the soft recoil gun are identified and obtained with the test data of the first round. ResultsThe similarity rate between the simulation and test data can reach up to 92.78%. Moreover, the corresponding simulation results match the test data under the second and third rounds. It is proved that the correct modeling and effective identification results provide theoretical guidance for the design of a soft recoil gun.

Dynamic Analysis and Optimization of a CTA Gun With the Soft Recoil Technology Based on Adams

Aimed at the object of the recoil minimization of a cased telescoped ammunition (CTA) gun with the soft recoil system, a dynamic model was establishedbased on the characteristics and the assumptions of the fire-out-of-battery(FOOB) principle and dynamic characteristics were obtained by Adams simulation analysis. Based on these results, an optimization model was established to reduce the recoil, and the key parameters of the firing platform were optimized by the optimization algorithm. The simulation results show that the maximum recoil was reduced about 10% without affecting system performance, which effectively improved the firing stability and the overall performance of the weapon system.

Parameters identification and forward rushing motion optimization for a big calibre soft recoil gun

Aiming to deal with the problem of the forward rushing velocity reduction caused by the increase of the firing angle of the soft recoil gun, a dynamical model of the soft recoil gun during forward rushing motion is established, and an improved immune clone selection algorithm is proposed. The vaccination strategy is introduced into the immune clone selection algorithm to improve the convergence speed. The random crossover strategy and elite learning mechanism enhances the ability to escape from the local extremes and avoids premature algorithmic maturity. Based on the introduction of the above three strategies, the convergence speed and calculation accuracy of the algorithm are improved, and the convergence time is greatly shortened which saves a lot of time for subsequent parameter identification and optimization calculations. By using the improved immune clone selection algorithm, the unknown parameters in the dynamical model can be identified accurately and quickly. Then, the parameters are used to correct the dynamical model which increase the accuracy of the optimization results. Finally, the algorithm is used to optimize the initial pressure of the gas spring in the forward momentum generator, so as to ensure that different firing angles have the same maximum forward rushing velocity, which improves the stability of the forward rushing motion and the reliability of the firing. Through the optimization calculation, the pressure variation curve of the gas spring with the change of the firing angle is finally determined. The forward rushing velocity is stable at 5.65m/s with different firing angles.

Summary and Prospect of Artillery Recoil Reduction Technology

Modern warfare has an urgent need for high-mobility and powerful artillery. However, the mobility and power of artillery are a contradiction. Recoil reduction technology is an important technical way to solve the contradiction between mobility and power. At present, there are many types of recoil reduction technologies, and the technical maturity and engineering application value of various technologies are different. For the development of new high-mobility and high-power artillery, which recoil reduction technology to adopt is a challenge. This article classifies and researches recoil reduction technology from the perspective of recoil energy dissipation. Based on the research and comparison of the basic principles, technical characteristics and application prospects of recoil reduction technology, it is concluded that the soft recoil technology using the principle of external neutralizing momentum is the best technical approach for the artillery system to realize high-mobility and high-power, where the potential application prospects of this technology in direct-target weapons are analysed.

Launch Dynamics Analysis of a Grenade Machine Gun with High Muzzle Velocity Based on the Soft Recoil Technology

To study the dynamic performance of a grenade machine gun system with soft recoil technology and analyze the floating mechanism parameters affecting the firing dispersion, a rigid-flexible coupling multi-body dynamics model was established. A twenty-round firing process of the grenade machine gun system was simulated and analyzed. The firing dispersion of the grenade machine gun system was obtained based on the external ballistics model, and the simulation model was validated by comparing the numerical results with the experimental data. The effects of the floating mechanism parameters on the cradle force, the projectile dispersion, and the firing dispersion sparsity were discussed. The results show that the projectile dispersion of the GMG system is well predicted by the simulation model, and the floating parameters that are matched reasonably could improve the firing dispersion and reduce the gun recoil force.

Non-global and rapidity logarithms in narrow jet broadening

We derive an all-order factorization theorem for the narrow jet broadening event shape, a measure of the transverse momentum in jet events. This is a non-global observable which receives logarithmically enhanced contributions associated with the large rapidity difference between soft and collinear radiation and which is also sensitive to soft recoil effects. Our work is the first factorization analysis of an observable of this type and we show that with regard to the non-global nature, the rapidity logarithms do not constitute an essential complication since they can be tied to the jet function, which is the same as for global observables. As a consequence, the leading non-global logarithms in narrow jet broadening are encoded in the same overall factor relevant for the hemisphere soft function and light jet mass.

연식주퇴 시스템 포신고정 장치의 동적 해석

In the soft recoil system, the recoiling parts are initially accelerated to the forward direction. These parts are returned to original position by the firing with intial acceleration speed. The latch of the soft recoil system keeps the high impact load when the recoil parts were recuperated to the forward direction. In this study, the latch of soft recoil system using the ADAMS program was analyzed. The optimal operation parameters were found that max. angle and expansion length of latch was <TEX>$50^{\circ}$</TEX>, 180 mm respectively. Dynamic structural analyses of model cases were performed using finite element model. The max. stress and deflection of latch was 230 MPa and 0.45 mm respectively.

Numerical and experimental studies on the dynamic behaviors of a gun that uses the soft recoil system

The conventional recoil mechanism of guns provides the retarding force on the gun to stop the rearward motion in the firing cycle. The concept of the soft recoil mechanism has been developed. This mechanism was introduced to reduce the firing shock and the reaction force due to the forward momentum of the recoiling parts prior to firing. This paper verifies the theory of the soft recoil mechanism and demonstrates its feasibility on a large-caliber gun system. Numerical simulation on recoil dynamics and shock response analysis were utilized in this study. A FORTRAN program, which was developed in a previous study, was employed for simulation. The shock re- sponse analysis utilized the shock response spectrum and the pseudo-velocity shock spectrum. As a result, a newly developed recoil sys- tem was proven to be applicable for guns in the near future with further refinements.

주퇴력 저감을 위한 연식 주퇴 메커니즘의 매개변수에 관한 연구

연식주퇴 메커니즘은 전방 운동량으로 주퇴력을 감소시키는 메커니즘이다. 연식주퇴 메커니즘에 영향을 미치는 매개변수는 사격 각도, 복좌기의 초기 압력, 발사위치등과 같이 다양하게 존재한다. 이런 매개변수들은 연식주퇴 메커니즘에서 전방 운동량을 결정짓는 요소가 된다. 연식주퇴 메커니즘의 설계를 위해 몇 가지 적당한 조건들을 고려하여 전방 운동량에 영향을 미치는 매개변수들에 대해 연구하였다. 여러 가지 매개변수들 중에서 복좌기의 초기 압력과 사격 위치가 전방 운동량에 영향을 미치는 중요한 요소로 확인하였다. 복좌기의 초기 압력이 180 일 때, 주퇴력이 가장 낮은 값을 가진다.

A formalism for the systematic treatment of rapidity logarithms in Quantum Field Theory

Many observables in QCD rely upon the resummation of perturbation theory to retain predictive power. Resummation follows after one factorizes the cross section into the rele- vant modes. The class of observables which are sensitive to soft recoil effects are particularly challenging to factorize and resum since they involve rapidity logarithms. In this paper we will present a formalism which allows one to factorize and resum the perturbative series for such observables in a systematic fashion through the notion of a "rapidity renormalization group". That is, a Collin-Soper like equation is realized as a renormalization group equation, but has a more universal applicability to observables beyond the traditional transverse momentum dependent parton distribution functions (TMDPDFs) and the Sudakov form factor. This formalism has the feature that it allows one to track the (non-standard) scheme dependence which is inherent in any scenario where one performs a resummation of rapidity divergences. We present a pedagogical introduction to the formalism by applying it to the well-known massive Sudakov form factor. The formalism is then used to study observables of current interest. A factorization theorem for the transverse momentum distribution of Higgs production is presented along with the result for the resummed cross section at NLL. Our formalism allows one to define gauge invariant TMDPDFs which are independent of both the hard scattering amplitude and the soft function, i.e. they are uni- versal. We present details of the factorization and resummation of the jet broadening cross section including a renormalization in pT space. We furthermore show how to regulate and renormalize exclusive processes which are plagued by endpoint singularities in such a way as to allow for a consistent resummation.

Design and characterization of a neutron calibration facility for the study of sub-keV nuclear recoils

We have designed and built a highly monochromatic 24 keV neutron beam at the Kansas State University Triga Mark-II reactor, as part of an experimental effort to demonstrate sensitivity in a large-mass detector to the ultra-low energy recoils expected from coherent neutrino-nucleus elastic scattering. The beam characteristics were chosen so as to mimic the soft recoil energies expected from reactor antineutrinos in a variety of targets, allowing to understand the response of dedicated detector technologies in this yet unexplored sub-keV recoil range. A full characterization of the beam properties (intensity, monochromaticity, contaminations, beam profile) is presented, together with first tests of the calibration facility using proton recoils in organic scintillator.

An Analytical Study of Fire Out of Battery Using Magneto Rheological Dampers

The application of magneto rheological dampers for controlling the dynamics of a fire out‐of‐battery recoil system is examined, using a dynamic simulation of a 105mm cannon. Upon providing a brief background on MR dampers and fire out‐of‐battery dynamics, we will describe the simulation model, along with some of the results obtained from the model. The simulation results show that although conventional hydraulic recoil dampers can be designed and tuned to control fire out‐of‐battery dynamics as effectively as MR dampers, they are not able to perform well when firing faults are encountered. The results show that MR dampers are able to adapt to the firing faults such as pre‐fire, hang‐fire, and misfire and provide "soft recoil" under all firing conditions. The inability of conventional hydraulic dampers to adapt to the firing faults can yield recoil dynamics that seriously jeopardize the performance of the gun. Therefore, the results presented here show that MR dampers may provide an enabling technology in achieving fire out‐of‐battery under all firing conditions.

Search for the neutrino magnetic moment in the nonequilibrium reactor-antineutrino energy spectrum

We study the time evolution of a typical reactor-antineutrino energy spectrum during the reactor operating period and the decay of the residual-antineutrino spectrum after the reactor is stopped. We find that relevant variations in the spectra of soft recoil electrons produced via weak and magnetic \(\bar \nu _e e\) scattering can play a significant role in current and planned searches for the neutrino magnetic moment at reactors.

Eikonal model with covariant recoil in relativistic quantum field theory in terms of a correlation expansion

A technique to derive covariant recoil to the eikonal model in relativistic quantum field theory is developed. Recoil is defined relative to the rectilinear-path approximation which gives the eikonal model. It appears in terms of a partially factorizable correlation expansion, where the first term is noncorrelated and is the usual eikonal model. The second term displays pair correlations, etc. By correlation here we mean dynamical correlation. Kinematical correlations due to four-momentum conservation are of course superimposed everywhere. We first consider soft recoil, and then generalize to the hard recoil, without introducing any cutoff. The technique is developed here for a scalar ${\ensuremath{\varphi}}^{3}$-type theory but it is general enough to be extended to, for example, quantum electrodynamics and scalar electrodynamics.

Correlation expansion in scalar electrodynamics

The recoil to the eikonal model in scalar electrodynamics is derived. We then make use of our generalization of Low's theorem, which in an earlier paper was derived for soft recoil due to real-photon emission to infinite order in the coupling constant. Here, we generalize this further to yield hard recoil due to virtual exchanged photons as well. Recoil is defined relative to the straight-line-path approximation which we know gives the eikonal model. The recoil appears in terms of a correlation expansion where the first term, which is noncorrelated, is the usual eikonal model. A second result is that this gives a better and more explicit alternative to a Bethe-Salpeter ladder amplitude, since our ladder includes all cirsscrosses.