Search results

The purpose of this paper is to investigate the effect of narrow gap on the fluid flow and heat transfer through an eccentric annular region is numerically. Flow through an eccentric annular geometry is a model problem of practical interest.

The approach involves standard finite volume-based SIMPLE scheme. The numerical simulations cover the practically relevant Reynolds number range of 104-106.

In the narrow gap region, temperature shoot up was observed due to flow maldistribution with an attendant reduction in the heat removal from the wall surfaces. CFD analysis is presented with the aid of, streamlines, isotherms, axial velocity contours, etc. The engineering parameters of interest such as, Nusselt number, wall shear stress, etc., is presented to study the effect of eccentricity and radius ratio.

The present investigation is a simplified model for the rod bundle heat transfer studies. However, the detailed study of sectorial mass flux distribution is a useful precursor to the thermal hydraulics of rod bundles.

For nuclear reactor fuel rods, the effect of eccentricity is going to be detrimental and might lead to the condition of critical heat flux. A thorough sub-channel analysis is very useful.

Nuclear safety standards require answers to a wide a range of what-if type hypothetical scenarios to enable preparedness. This study is a highly simplified model and a first step in that direction.

The narrow gap region has been systematically investigated for the first time. A detailed sectorial analysis reveals that, flow maldistribution and the attendant temperature shoot up in the narrow gap region is detrimental to the safe operation.

This paper aims to study the effects of a diet supplemented with flaxseeds on dyslipidemia, oxidative stress and proinflammatory cytokines, in rats consuming a high-cholesterol diet.

Male Wistar rats (n = 30) weighing (250 ± 5 g) of which 10 were control and 20 were rendered hypercholesterolemic (HC) by feeding a diet enriched with 1% of cholesterol, for 15 days. After this phase, rats were divided into two groups; hypercholesterolemic group (HC) (n = 10), fed 20% casein diet enriched with 1% cholesterol; and hypercholesterolemic rats fed the same diet (n = 10), but additionally supplemented with flaxseeds (Linum usitatissimum) (Lu) powder, i.e. HC-Lu. Animals of the control group (n = 10) were fed the casein diet. All the animals were maintained on the respective diets for four weeks.

This study showed that in HC-Lu as compared to HC group, plasma total cholesterol, triacylglycerols and non-HDL cholesterol concentrations were respectively 2.4-, 1.5- and 3-fold lower. Also, the lipid peroxidation was reduced in red blood cells, organs (liver, heart and aorta) and lipoproteins (HDL2, HDL3 and VDL-LDL). A higher superoxide dismutase activity was observed in liver (+61%), heart (+62%) and aorta (+59%), whereas plasma proinflammatory cytokine (IL-1beta and IL-6) levels were decreased.

These results suggest that flaxseeds help to reduce hypercholesterolemia, oxidative stress and inflammation in patients with hypercholesterolemia.

The main purpose of the research paper is to study the effect of refinement of primary silicon on sliding wear behavior of commercially available LM-28 alloy and correlate these with the micro-structural and mechanical properties. It is well known that the refinement of primary silicon increases the toughness, ultimate tensile stress (UTS) and wear resistance of the Al-Si alloys at ambient temperature. But exact addition level is not clearly mentioned in the paper; hence, the present paper throws light on the addition level for refinement of primary silicon present in LM-28 alloy.

In the present paper, commercially available LM-28 alloy was prepared in the laboratory before and after the addition of Cu-P master alloy. Further wear studies will be carried out at room temperature. Wear properties are correlated with microstructure and mechanical properties.

Improvements in mechanical properties were observed after refinement of the primary silicon present in LM-28 alloy.

Further studies are required regarding in-depth investigation of refinement of primary silicon and its effects on the life of the components prepared by this alloy.

The data obtained from the research paper help the manufacturers of automotive, aerospace and marine components, such as pistons, cylinder heads and blocks, etc.

The present research work will be an essential information required for the students of undergraduate, postgraduate and research scholars to carry out research at an R&D centre.

Experiments are conducted at an R&D centre and analyses were carried out for structural changes, mechanical properties and wear properties. Further, the results are compared with other researcher’s data.

The purpose of this study is to identify major themes and potential research opportunities in online and offline consumer search.

A systematic review was conducted based on 118 articles identified from prevalent journal databases. Keywords frequency analysis was carried out to identify the major themes. An inductive thematic analysis was carried out to verify the generated themes.

Results show that uncertainty, knowledge, perceived risk, price, experience and involvement are the major themes associated with consumer information search. Uncertainty, one of the major themes of offline search, has not been studied in the online search context. Similarly, the previous experience needs to be explored in the context of the offline search. Finally, potential research opportunities for future research has been summarized based on the retrieved themes.

The systematic review provides an in-depth understanding on the current research on information search literature with future research directions.

This study helps retailers to understand the key elements that motivate consumers to perform external information searches from online and offline sources and to curate targeted information provision strategies to influence purchase decisions.

Consumers with limited internet availability may access channels prior to decision-making. The themes identified in this study can aid policymakers to design affordable access to these channels.

This study adds to the sparse literature on systematic reviews on consumer search for online and offline channels.

The purpose of the present paper aims to, study the coefficient of friction and wear behavior of nickel based super alloys used in manufacturing of gas and steam turbine blades. In present paper, parametric study focuses on normal load, dry sliding velocity and contact temperature influence on coefficient of friction and wear of a nickel based super alloy material.

Experimental investigation is carried out to know the effect of varying load at constant sliding velocity and varying sliding velocity at constant load on coefficient of friction and wear behavior of nickel based super alloy material. The experiments are carried out on a nickel based super alloy material using pin on disk apparatus by load ranging from 30 N to 90 N and sliding velocity from 1.34 m/s to 2.67 m/s. The contact temperature between pin and disk is measured using K-type thermocouple for all test conditions to know effect of contact temperature on coefficient of friction and wear behavior of nickel based super alloy material. Analytical calculations are carried out to find wear rate and wear coefficient of the test specimen and are compared with experimental results for validation of experimental setup. Regression equations are generated from experimental results to estimate coefficient of friction and wear in the range of test conditions.

From the experimental results, it is observed that by increasing the normal load or sliding velocity, the contact temperature between the pin and disk increases, the coefficient of friction decreases and wear increases. Analysis of variance (ANOVA) is used to study the influence of individual parameters like normal load, dry sliding speed and sliding distance on the coefficient of friction and wear of nickel based super alloy material.

This is the first time to study effect of contact temperature on the coefficient of friction and wear behavior of nickel-based super alloy used for gas and steam turbine blades. Separate regression equations have been developed to determine the coefficient of friction and wear for the entire range of speed of gas turbine blades made of nickel based super alloy. The regression equations are also validated against experimental results.

Aerospace field is demanding a material with superior strength and high resistance against wear, tear and corrosion. The current study aimed to develop a new material with high performance to be applicable in aerospace field

A metal matrix composite AA8090-WC-ZrC was fabricated using stir casting method and its tribological behavior was investigated. Totally, five composites viz. AA/Z, AA/W, AA/WZ (1:3), AA/WZ (1:1) & AA/WZ (3:1) were prepared. Micro hardness, tensile and wear study were performed on the fabricated composites and the results were compared with AA8090 alloy

Vickers hardness test resulted that the AA/W composite showed the higher hardness value of 160 HB compared to other materials due to the reinforcing effect of WC particles with high hardness. Tensile test reported that the AA/W composite displayed the maximum tensile strength of 502 MPa owing to the creation of more dislocation density. Further, wear study showed that the AA/W composite exhibited the least wear rate of 0.0011 mm3/m because of the more resisting force offered by the WC particles. Furthermore, the AA/W composite showed the slightest mass loss of 0.0028 g and lower COF value of 0.31 due to the hinder effect of WC particle to the movement of atoms in AA8090 alloy

This work is original in the field of aerospace engineering and materials science which deals with the fabrication of AA8090 alloy with the reinforcement particles such as tungsten carbide and zirconium carbide. The impact of the combination of hybrid particles and their volume fractions on the tribological properties has been investigated in this work. This work would provide new scientific information to society.

The researchers aim to investigate the role of psychological capital (PsyCap) in facilitating intrinsic motivation and goal-commitment among employees at the workplace, affecting outcome variables, namely, in-role and extra-role job performance.

Data were collected from 640 employees working in the information technology sector of India. Covariance-based structural equation modeling (CB-SEM) was used to test the hypothesized relationships.

Analysis revealed a significant positive impact of PsyCap on the two behavioral facets of job performance. Intrinsic motivation and goal-commitment were found mediating the influence of PsyCap on the two facets of job performance.

The information technology sector is characterised by continuous change. It requires voluntary prosocial behavior from employees, where the employees are expected to display multifaceted job performance behaviors, where they go beyond their job duties to cater for the dynamics of the IT sector. The present study provides means by which intrinsic motivated and goal-committed behavior are facilitated for both the in-role and extra-role job performance.

The present study is among the few preliminary studies that have provided evidence that intrinsic motivation and goal-commitment are the two variables which aid PsyCap in predicting both the prescribed and voluntary job performance behaviors.

The purpose of the paper was to assess the functional properties vegetable gourds & the validated health claims so as to help the future researchers to locate the gaps. However, emphasizing on the scientifically available reports was required to make information available in a nutshell to the health-conscious consumers, as well as the researcher from the area of functional foods and nutrition.

The paper is a mini-review of scientific findings in different studies on gourd vegetables. The approach to information collection was finding the research gaps and potential areas for future work with a nutritional perspective.

Ash gourd, bitter gourd and bottle gourd have been extensively studied, and several health benefits and functional components have been reported, while ridge gourd, snake gourd and pointed gourd have been sparsely studied for their therapeutic benefits and the validation thereof; hence, there lies a scope for researchers.

The scarcity of scientific reports compared to the traditional usage and folkloric beliefs was a limitation.

Understanding the nutritional potential of gourd vegetables from scientific reports may influence both the work areas and consumers in the appropriate direction.

The purpose of this paper is to study the wear behavior of as‐cast (AC) and heat treated (HT) triple particle size (TPS) silicon carbide (SiC) reinforced aluminum alloy‐based metal matrix composites (SiC_p/Al‐MMC).

Al‐MMCs were prepared using 20 vol.% SiC reinforcement into aluminum metal matrix and developed using a stir casting process. Stir casting is a primary process of composite production whereby the reinforcement ingredient material is incorporated into the molten metal by stirring. The TPS composite consist of SiC of three different sizes viz., coarse, intermediate, and fine. The solution heat treatment was done on AC composite at 540°C for 4 h followed by precipitation treatment. The wear test was carried out using a pin‐on‐disc type tribo‐test machine under dry sliding condition. A mathematical analysis was also done for power factor values based on wear and friction results. The wear morphology of the damaged surface was also studied using optical microscope and scanning electron microscope (SEM) in this investigation.

The test results showed that HT composite exhibited better wear resistance properties compared to AC composite. It is anticipated that heat treatment could be an effective method of optimizing the wear resistance properties of the developed Al‐MMC material.

This paper provides a way to enhance the wear behavior of automotive tribo‐components such as brake rotor (disc and drum), brake pad, piston cylinder, etc.

This paper compares the wear behavior of AC and HT TPS reinforced Al‐MMC material under dry sliding condition.