Corrugated composite plate with different profile may be of interest for energy absorption application due to their improved crashworthiness. In the current paper, square profile corrugated composite plates made of fiber glass reinforced plastic (FGRP) are introduced as energy absorption structure. Different arrangements of the corrugated plate are tested. In addition to that, the effect of placing a flat composite plate made from same material is studied experimentally. Multilayers (single, double, and triple layers) of the square profile corrugated composite plates have been fabricated and tested under the same condition. The tested specimens are subjected to quasi-static compression load. The well-known crashworthiness parameters are being recorded and used to compare the different configurations.

The article presents the effect of dimensions and geometry on the crushing behavior, energy absorption, failure mechanism, and failure mode of woven roving glass fiber/epoxy laminated composite tube. Three sizes (big CCT1, medium CCT2, and small CCT3) of cylindrical composite tubes (CCT) were fabricated and tested under the same conditions. Comprehensive experimental work was conducted that includes axial and lateral quasi-static crushing test to examine the influence of the design parameters on the energy absorption characteristics of CCT. Load–displacement curves and deformation histories were presented and discussed. Different parameters were obtained from studying of load–displacement curves, these parameters are: initial failure load, average crushing load, and total energy absorption.

The main objective of this article is to study composite structures as an energy absorption system. The method of approach has been to fabricate and test a series of composite plates with sinusoidal corrugation profile. These plates have been subjected to compression load. In order to achieve this aim, an extensive experimental as well as theoretical study has been conducted. Tested specimens were fabricated and tested in the same conditions. In addition to that, multi layers of composite plates with sinusoidal profiles were fabricated and tested. Results showed that the specific energy absorption and load carrying capacity increased with the increase of the number of corrugated plates. It has been found that, the relationship between the two factors is directly proportional.

This article presents the quasi-static crushing performance of six different geometrical shapes of small scale corrugated composite plates with triangular profile. The idea is to understand the effect of corrugation profile, and number of layers on the progressive deformation and energy absorption capability of corrugated composite plates of triangular profile with multi layers. Different corrugated composite plates of triangular profile with single, double, and triple layers have been manufactured by hand layup technique using woven roving fiber glass/epoxy. In addition to that, flat composite plates have been made using same materials. These plates have been placed in-between some specimens of corrugated composite plates. Several quasi-static tests have been conducted for all six shapes of tested models under same conditions.

This study focuses on the steady-state thermal hydraulic analysis of the reactor of the Tajoura Nuclear Research Centre (TNRC) with LOW Enriched Uranium (LEU) core. A MATLAB program has been constructed to calculate the important related safety parameters at the steady-state operation of the core. The calculations have been performed at the hottest cell of the core and at the operating power of 10 MW with coolant inlet temperature equals to 45 °. The benefit of the symmetry of the shape of the core cells has been used to divide the hottest cell to four regions. Each quarter of the hottest cell has been further divided to a plate part and a corner part. Therefore, the calculations have been applied to the quarter of the hottest cell at both plate and corner parts. The assessment of the operating power according to the maximum allowable clad surface temperature is used to identify the maximum operating power of TNRC's reactor. The outcome of this investigation is that the reactor of the TNRC must not operate at power equals to 10 MW and the maximum allowable operating power is 9.7 MW where the value of the maximum clad surface temperature is 101.7 ° (maximum allowable clad surface temperature = 102 °). The results have been compared witha previous studies [1] where a Nusselt number is calculated using a different correlation equation from this study. [2] where an onset of nucleate boiling (ONB) and the maximum allowable power are tested and with the results of a team at Argonne National Lab, ANL, [3] Which present a good agreement.

Three postulated initiating events are explored in order to investigate the safety of the reactor of the Tajoura Nuclear Research Reactor with Low Enriched Uranium )LEU). these initiated events are: ramp insertion of a positive reactivity; a reduction of flow of primary coolant (failure of one pump or coast down of two pumps); and a loss of flow accident (LOFA) followed by a reversal flow. PARET computer code is implemented to simulate those suggested initiating events. The transient thermal hydraulic analysis is obtained at both the hottest and averaged cells of the core. the simulation is carried out at different operating power levels of 9.7MW, 9MW, and 5MW. The inlet coolant temperature equals to 45 ° and the average peaking factors are Fxy=2.64 and Fz=1.26. The results exhibit that the worst case of those examined postulated events occurs when the primary coolant flow is reduced due to the collapse of two pumps and the corresponding maximum clad surface temperature reaches to 130.04 °. This assessment assures the safety of the reactor of the TRNC while one of these examined initiating events takes place.

Abstract

This paper presents a series of experiments and numerical simulations using commercial software (ANSYS) to determine the behaviour and impact on the blowoff process with various geometries and simulated syngas compositions at fixed power outputs. Experiments were performed using a generic premixed swirl burner. The Central Recirculation Zone and the associated turbulent structure contained within it were obtained through CFD analyses providing details of the structures and the Damkolher Number (Da) close to blowoff limits. The results show how the strength and size of the recirculation zone are highly influenced by the blend, with a shift of Da and turbulence based on carbon-hydrogen ratio, shearing flows and Reynolds number. Instabilities such as thermoacoustics, flashback, autoignition and blowoff are highly affected by the flow structures and chemical reactions/diffusivity. Moreover, it has been observed that turbulence close to the boundaries of the central recirculation zone, a region of high stability for swirling flows, is highly altered by the chemical characteristics of the fuel blends. In terms of blowoff, the phenomenon is still not entirely understood. As the process occurs, its theoretical limits do not match its real behaviour. Therefore, one possibility could be the difference in turbulence and Da numbers across the flame, being critical at the base of the flame where the system is stabilized. 

Usually fin represent as one of the important structures in all type of airplane and the fin structure was greatly improved, especially for modern supersonic speed constructions. The main aim of delta fin construction is to minimize the weight of structure as much as possible and keeping the stiffness of material structural in margin of safety under design load [1]. The primary difference between classical method and finite element are the view structure and the ensuring solution procedure. Classical method considers the structure as a continuum whose behavior is governed by partial or ordinary differential equations [2]. By using finite element method consider the structure to be an assembly of small finite-sized particles. The behavior of the particles and the overall structure is obtained by formulating a system of algebraic equation that can be readily solved by developed methodology, which will be presented in form of software.

The use of gas for power generation is likely to increase in the medium term. Also, the introduction of new fuels will ensure a higher generation with lower emissions under continuous operation. These scenarios lead to the conclusion that there will be a considerably more diverse range of fuel supply. However, the use of these new fuels contrasts with recent experiences of global operators who report increasing emissions and difficult combustion dynamics with even moderate variations in their fuel characteristics. Clearly there are significant challenges for fuel flexible gas turbines, particularly emission control, combustor dynamics and flame stability.

Trials using a power derivative gas turbine combustor and a high hydrogen content fuel produced unusual flashback events, in that flashback was induced by either leaning of the fuel mixture by the increase of combustion air, or by a change in composition through the reduction of methane pilot fuel. The introduction of CO₂ through the combustors pilot injector prevented flashback from occurring under these circumstances. The resulting reduction of temperature in the combustion zone, indicated by lower burner tip temperatures causes a reduction in the emissions of nitrous oxides, whilst there is minimal effect on the effective turbine inlet temperature, only a 2.3% reduction.

Investigations using a ‘generic’, radial swirl burner and stereo PIV demonstrated how the flashback depended on a combination of flow structure augmentation and changes in mixture burning rate. The injection of methane or CO₂ had differing effect on these parameters of the combustion zone, but both produced combinations that facilitated stability.

This paper presents an application of the hazard model reliability analysis on wind generators, based on a condition monitoring system. The hazard model techniques are most widely used in the statistical analysis of the electric machine’s lifetime data. The model can be utilized to perform appropriate maintenance decision-making based on the evaluation of the mean time to failures that occur on the wind generators due to high temperatures. The knowledge of the condition monitoring system is used to estimate the hazard failure, and survival rates, which allows the preventive maintenance approach to be performed accurately. A case study is presented to demonstrate the adequacy of the proposed method based on the condition monitoring data for two wind turbines. Such data are representative in the generator temperatures with respect to the expended operating hours of the selected wind turbines. In this context, the influence of the generator temperatures on the lifetime of the generators can be determined. The results of the study can be used to develop the predetermined maintenance program, which significantly reduces the maintenance and operation costs.