scholarly journals Effect of Hull Obliquity on Crew Protection, Mass and Space Occupancy of Light Armoured Vehicle

2021 ◽  
Vol 71 (5) ◽  
pp. 619-629
Author(s):  
Wibneh Amare ◽  
Ashish Kumar Singh ◽  
Sougata Karmakar

Apart from strengthening crew protective capability from gunfire, the hull obliquity in a light armoured vehicle (LAV) affects its weight and comfortable occupancy. Thus, it requires a critical design analysis for the obliqued hull. The study aims to present the optimal design analysis of an obliqued hull structure to ensure comfortable occupancy of the crew along with its minimum attainable weight and higher protection capability from the gunfire. Three geometric models (G1, G2, and G3) were investigated for the LAV hull’s optimal design. The analytical approach was used to investigate the hull obliquity’s effect, and the results were validated using experimental data reported by other researchers. Digital human modelling was adopted for validating the space adequacy of the hull. It was observed that the hull’s crew protection capabilities from the horizontal strike of armour piercing rounds/bullets were improved almost by half and double for G2 and G3, respectively, when compared with G1. The analytical results are also in good agreement with globally accepted experimental data at reasonable variations. The highest protection capability and comfortable occupancy for the targeted users can be achieved by G3 without affecting the mobility of LAV.

2011 ◽  
Vol 243-249 ◽  
pp. 5458-5464 ◽  
Author(s):  
Li Xiong Gu ◽  
Zhi Fang Liu ◽  
Zhong Yong Xu

Since the pioneering work of Paris and Erdogan (1963), the fatigue crack growth (FCG) model has been being modified by worldwide researchers. Research efforts have been devoted by a number of investigators for assessing the fatigue condition of structural components by means of residual stress at the crack tip, threshold stress intensity factor, load ratio, and so on. The parameter C is always as a constant about material and structure, and almost no further research on it. In this paper, we proposed a novel analytical approach to predict the effect of the parameter C on fatigue performance. The inertial effect coefficient model for FCG under constant amplitude (CA) loading is briefly described and then used to verify the parameter C is a variable and analyze the relation between the parameter C and FCG rate. The prediction of the parameter C in this model is in good agreement with experimental data taken from the literature.


2019 ◽  
Vol 34 (09) ◽  
pp. 1950073 ◽  
Author(s):  
Mohsen Mousavi ◽  
Mohammad Reza Shojaei

In this study, some static properties of odd isotopes of Ca were investigated in the non-relativistic shell model. We also suggested a novel suitable local potential model for the non-microscopic investigation of the mentioned nuclei. We modeled the odd [Formula: see text]Ca nuclei as doubly-magic isotopes with further nucleons (valence) in the [Formula: see text] and [Formula: see text] levels. Then, the modified Eckart potential plus Hulthen potential were chosen for the interaction between core and nucleons. We also used the parametric Nikiforov–Uvarov method to calculate the values of energy, the radius of charge and wave function. The obtained results showed a good agreement with the experimental data, so this model is applicable for the similar nuclei.


Author(s):  
Li Liu ◽  
Jyhwen Wang

Metal-polymer-metal laminate is an emerging material that has many potential applications. The laminated structure consists of two outer layers of sheet metal and a polymeric center core. The material offers an excellent sound deadening properties and is being introduced to applications where noise reduction is desired. Part manufacturing for laminates involves converting a flat sheet into a deformed body. Springback has been a major concern in shape control. While bending of a single layered sheet metal does not exhibit significant sidewall curl, the problem is pronounced in bending laminates. This paper presents an analytical approach to predict springback and sidewall curl of laminates due to simple bending. Based on the models, springback factor Ks is calculated. It is shown that the prediction is in good agreement with the published experimental data.


2020 ◽  
pp. 149-152

The energy states for the J , b , ɤ bands and electromagnetic transitions B (E2) values for even – even molybdenum 90 – 94 Mo nuclei are calculated in the present work of "the interacting boson model (IBM-1)" . The parameters of the equation of IBM-1 Hamiltonian are determined which yield the best excellent suit the experimental energy states . The positive parity of energy states are obtained by using IBS1. for program for even 90 – 94 Mo isotopes with bosons number 5 , 4 and 5 respectively. The" reduced transition probability B(E2)" of these neuclei are calculated and compared with the experimental data . The ratio of the excitation energies of the 41+ to 21+ states ( R4/2) are also calculated . The calculated and experimental (R4/2) values showed that the 90 – 94 Mo nuclei have the vibrational dynamical symmetry U(5). Good agreement was found from comparison between the calculated energy states and electric quadruple probabilities B(E2) transition of the 90–94Mo isotopes with the experimental data .


1977 ◽  
Vol 5 (1) ◽  
pp. 6-28 ◽  
Author(s):  
A. L. Browne

Abstract An analytical tool is presented for the prediction of the effects of changes in tread pattern design on thick film wet traction performance. Results are reported for studies in which the analysis, implemented on a digital computer, was used to determine the effect of different tread geometry features, among these being the number, width, and lateral spacing of longitudinal grooves and the angle of zigzags in longitudinal grooves, on thick film wet traction. These results are shown to be in good agreement with experimental data appearing in the literature and are used to formulate guidelines for tread groove network design practice.


2015 ◽  
Vol 11 (3) ◽  
pp. 3224-3228
Author(s):  
Tarek El-Ashram

In this paper we derived a new condition of formation and stability of all crystalline systems and we checked its validity andit is found to be in a good agreement with experimental data. This condition is derived directly from the quantum conditionson the free electron Fermi gas inside the crystal. The new condition relates both the volume of Fermi sphere VF andvolume of Brillouin zone VB by the valence electron concentration VEC as ;𝑽𝑭𝑽𝑩= 𝒏𝑽𝑬𝑪𝟐for all crystalline systems (wheren is the number of atoms per lattice point).


1982 ◽  
Vol 14 (4-5) ◽  
pp. 253-256
Author(s):  
N Sriramula ◽  
M Chaudhuri

An investigation was undertaken on the removal of a model virus, bacterial virus MS2 against Escherichia coli, by sand filtration using untreated, and alum or cationic polyelectrolyte treated media, and uncoagulated as well as alum coagulated influent. Data on discrete virus removal were satisfactorily accounted for by electrokinetic phenomena and diffusion. For virus in association with turbidity, filter coefficients computed from experimental data were in good agreement with those predicted by mechanical straining and gravity settling which were the dominant mechanisms for removal of the turbidity particles to which the viruses attached.


1991 ◽  
Vol 56 (10) ◽  
pp. 2020-2029
Author(s):  
Jindřich Leitner ◽  
Petr Voňka ◽  
Josef Stejskal ◽  
Přemysl Klíma ◽  
Rudolf Hladina

The authors proposed and treated quantitatively a kinetic model for deposition of epitaxial GaAs layers prepared by reaction of trimethylgallium with arsine in hydrogen atmosphere. The transport of gallium to the surface of the substrate is considered as the controlling process. The influence of the rate of chemical reactions in the gas phase and on the substrate surface on the kinetics of the deposition process is neglected. The calculated dependence of the growth rate of the layers on the conditions of the deposition is in a good agreement with experimental data in the temperature range from 600 to 800°C.


Author(s):  
Emre Kahramanoglu ◽  
Silvia Pennino ◽  
Huseyin Yilmaz

The hydrodynamic characteristics of the planing hulls in particular at the planing regime are completely different from the conventional hull forms and the determination of these characteristics is more complicated. In the present study, calm water hydrodynamic characteristics of planing hulls are investigated using a hybrid method. The hybrid method combines the dynamic trim and sinkage from the Zarnick approach with the Savitsky method in order to calculate the total resistance of the planing hull. Since the obtained dynamic trim and sinkage values by using the original Zarnick approach are not in good agreement with experimental data, an improvement is applied to the hybrid method using a reduction function proposed by Garme. The numerical results obtained by the hybrid and improved hybrid method are compared with each other and available experimental data. The results indicate that the improved hybrid method gives better results compared to the hybrid method, especially for the dynamic trim and resistance. Although the results have some discrepancies with experimental data in terms of resistance, trim and sinkage, the improved hybrid method becomes appealing particularly for the preliminary design stage of the planing hulls.


Sign in / Sign up

Export Citation Format

Share Document