•Location of DGs based on existing sensitivity methods.•Proposing combined power loss sensitivity based method for DG location and sizing.•Modified Novel method for DG location and sizing.•Comparison ...of proposed and existing sensitivity methods.•Determining cost of losses and power obtained from DGs.
Integration of renewable energy based distributed generation (DG) units provides potential benefits to conventional distribution systems. The power injections from renewable DG units located close to the load centers provide an opportunity for system voltage support, reduction in energy losses, and reliability improvement. Therefore, the location of DG units should be carefully determined with the consideration of different planning incentives. This paper presents a comparison of novel, combined loss sensitivity, index vector, and voltage sensitivity index methods for optimal location and sizing of distributed generation (DG) in a distribution network. The main contribution of the paper is: (i) location of DGs based on existing sensitivity methods, (ii) proposing combined power loss sensitivity based method for DG location, (iii) modified Novel method for DG location, (iv) comparison of sensitivity methods for DG location and their size calculations, and (v) cost of losses and determining cost of power obtained from DGs and the comparison of methods at unity and lagging power factors. The results show the importance of installing the suitable size of DG at the suitable location. The results are obtained with all sensitivity based methods on the IEEE 33-bus and 69-bus systems.
The analysis of axial dispersion of solute is presented in a pulsatile flow of Casson fluid through a tube in the presence of interfacial mass transport due to irreversible first-order reaction ...catalysed by the tube wall. The theory of dispersion is studied by employing the generalized dispersion model proposed by Sankarasubramanian & Gill (Proc. R. Soc. Lond. A, vol. 333 (1592), 1973, pp. 115–132). This dispersion model describes the whole dispersion process in terms of three effective transport coefficients, i.e. exchange, convection and dispersion coefficients. In the present study, the effects of yield stress of Casson fluid
${\it\tau}_{y}$
, wall absorption parameter
${\it\beta}$
, amplitude of fluctuating pressure component
$e$
and Womersley frequency parameter
${\it\alpha}$
on the dispersion process are discussed under the influence of pulsatile pressure gradient. In a pulsatile flow, the plug flow radius changes during the period of oscillation and it has an effect on the dispersion process. Even with the Casson fluid model also, in an oscillatory flow, for small values of
${\it\alpha}$
, the dispersion coefficient
$K_{2}$
is positive, but when the value of
${\it\alpha}$
is as large as 3,
$K_{2}$
takes both positive and negative values due to the fluctuations in the velocity profiles. This nature becomes more predominant for
${\it\tau}_{y}$
,
$e$
and
${\it\beta}$
. It is observed that initially, for small time, the amplitude and magnitude of fluctuations of
$K_{2}$
becomes more rapid and increases with time but it decreases after certain time and reaches a non-transient state for large time. Like in the case of Newtonian model, double frequency period for
$K_{2}$
is observed at small time for large values of
${\it\alpha}$
with the Casson model for blood. It is seen that critical time for which
$K_{2}$
reaches a non-transient state is independent of
${\it\tau}_{y}$
and
$e$
but is dependent on
${\it\alpha}$
. It is also observed that the axial distribution of mean concentration
$C_{m}$
of solute depends on
${\it\tau}_{y}$
and
${\it\beta}$
. But the effect of
$e$
and
${\it\alpha}$
on
$C_{m}$
is not very significant. This dispersion model in non-Newtonian pulsatile flow can be applied to study the dispersion process in the cardiovascular system and blood oxygenators.
In this investigation, we intend to present the influence of the prominent Soret effect on mixed convection heat and mass transfer in the boundary layer region of a semi-infinite vertical flat plate ...in a nanofluid under the convective boundary conditions. The transformed boundary layer ordinary differential equations are solved numerically using the implicit iterative finite difference method. Consideration of the nanofluid and the convective boundary conditions enhanced the number of non-dimensional parameters considerably thereby increasing the complexity of the present problem. A wide range of parameter values is chosen to bring out the effect of Soret parameter on the mixed convection process with the convective boundary condition. The effect of mixed convection, Soret and Biot parameters on the flow, heat and mass transfer coefficients is analyzed. The numerical results obtained for the velocity, temperature, volume fraction, and concentration profiles, as well as the local skin-friction coefficient, local wall temperature, local nanoparticle concentration and local wall concentration reveal interesting phenomenon, some of these qualitative results are presented through plots and tables.
In this numerical study, a two-dimensional double-diffusive convective flow of a hybrid nanofluid in an inverted T-shaped porous media has been thoroughly investigated. The governing equations ...comprise the generalized Darcy-Forchheimer-Brinkman-based model along with the heat and mass transport equations. Furthermore, a penalty finite element approach has been employed for numerical simulation of the evolved mathematical model at the broad range of pertinent influencing parameters, including buoyancy ratio (N), Lewis number (Le), Darcy number (Da), and porosity value (ϵ) as a function of Rayleigh number (Ra). The results and discussion have been demonstrated through the results variations of streamlines, isotherms, isoconcentration, mean Nusselt (Nu
m
), and Sherwood number (Sh
m
) at the considered range of flow parameters. The results show that the smaller
Ra
≤
10
5
values remain insignificant for convective heat and mass transport efficiency, whereas augmentation of
Ra
≥
10
5
reinforces these flows. Moreover, higher Ra values help in studying the real influence of other pertinent parameters. The increasing value of ϵ and Da strengthen the convection fluid, heat, and solute transfer intensity. In the case of Lewis number, a notable effect on improving the solute transport rate is more dominant than the heat transport rate. Similarly, the flow regime of fluid and solute, as well as heat and mass transfer rate, are significantly influenced by ranging values of buoyancy ratio (
−
4
≤
N
≤
4
). The buoyancy-added flow (N > 1) improves the convective strength of heat and mass flow rate more effectively than the buoyancy-opposed flow (N < 1). Furthermore, the variation of Nu
m
and Sh
m
justify the results interpreted in each flow parameter.
We investigate the convective heat and mass transfer in nanofluid flow over a stretching sheet subject to hydromagnetic, viscous dissipation, chemical reaction and Soret effects. Two types of ...nanofluids, namely Cu–water and Ag–water were studied. A similarity transformation was used to obtain a system of non-linear ordinary differential equations, which was then solved numerically using the Matlab “bvp4c” function. Numerical results were obtained for the skin friction coefficient, Nusselt number, Sherwood number as well as for the velocity, temperature and concentration profiles for selected values of the governing parameters, such as the nanoparticle volume fraction ϕ, the magnetic parameter M. For a fixed Prandtl number Pr=6.2 (corresponding to water) and different values of the magnetic field parameter and the nanoparticle volume fraction, we have shown that a good agreement exists between the present results and those in the literature. It was shown that the Cu–water nanofluid exhibits higher wall heat and mass transfer rates as compared to a Ag–water nanofluid. The influence of a magnetic field is to reduce both wall heat and mass transfer rates.
In the present work, an artificial neural network (ANN) model has been developed to predict the bit–rock interface temperature using a newly fabricated grounded K-type thermocouple (range 0–1250 °C) ...during rotary drilling in a CNC vertical machining center. The data have been taken from experimental observation using an embedded thermocouple technique in the laboratory at room temperature (28 °C) using a masonry drill bit. The observations were made using four different operational conditions, namely drill bit diameter (6, 8, 10, 12 and 16 mm), spindle speed (250, 300, 350, 400 and 450 rpm), rate of penetration (2, 4, 6, 8 and 10 mm min
−1
) and depth (6, 14, 22 and 30 mm). The ANN has been developed based on the multi layer perceptron neural network (MLPNN) with four different input parameters. A Levenberg–Marquardt (LM) algorithm with feed-forward and backward propagation has been used in this model. The predicted value of the bit–rock interface temperature with the highest
R
2
value provides a satisfactory result with the experimental data. The training value of RMSE is 1.2127, MAPE is 0.0196 and
R
2
is 0.9960, while the testing value of RMSE is 1.2770, MAPE is 0.0170 and
R
2
is 0.9978. The ANN model shows that the proposed MLPNN model successfully predicts the bit–rock interface temperature during the rotary drilling of limestone.
Oxidative stress and inflammation are two important pathological mechanisms involved in cerebral ischemia and reperfusion injury. In pathological conditions such as cerebral infarction, the free ...radical production is greater than that of elimination by endogenous anti-oxidant system, by this undesirable effect brain is highly injured. Resveratrol is reported to have anti-oxidant and anti-inflammatory, athero-protective activities. Therefore, the aim of the present study is to evaluate the therapeutic potential of resveratrol against cerebral infarction induced by ischemia and reperfusion injury in Wistar rats. Bi-common carotid occlusion followed by 4 h reperfusion model was used to induce cerebral infarction. Percent infarction, oxidative stress markers (malondialdehyde, catalase, superoxide dismutase) and inflammatory markers (myeloperoxidase, TNF-α, IL-6, ICAM-1 and IL-10) were measured. TNF-α, IL-6, IL-10, and intracellular adhesive molecule-I (ICAM-1) levels were quantified by enzyme-linked immunosorbent assay (ELISA). Resveratrol produced significant dose-dependent reduction in percent cerebral infarct volume. At resveratrol 20 mg/kg dose, there was a significant reduction in oxidative stress and inflammatory markers like malondialdehyde, TNF-α, IL-6, myeloperoxidase and ICAM-I and in contrast there was a significant increase in anti-oxidants and anti-inflammatory markers like superoxide dismutase, catalase and IL-10 levels. Resveratrol showed significant cerebroprotective action mediated by anti-oxidant and anti-inflammatory mechanisms.
A facile, one-pot, and proficient method was developed for the production of various 2-arylaminobenzimidazoles. This methodology is based for the first time on a copper catalyst promoted domino C-N ...cross-coupling reaction for the generation of 2-arylaminobenzimidazoles. Mechanistic investigations revealed that the synthetic pathway involves a copper-based desulphurization/nucleophilic substitution and a subsequent domino intra and intermolecular C-N cross-coupling reactions. Some of the issues typically encountered during the synthesis of 2-arylaminobezimidazoles, including the use of expensive catalytic systems and the low reactivity of bromo precursors, were addressed using this newly developed copper-catalyzed method. The reaction procedure is simple, generally with excellent substrate tolerance, and provides good to high yields of the desired products.
This research aims to enhance convective thermal transport in an inverted T-shaped porous enclosure filled with a water-based hybrid nanofluid, incorporating a circular cylinder at different vertical ...locations (Case C1-no cylinder, Case C1-cylinder at (0.5, 0.25), Case C2-cylinder at (0.5, 0.5), Case C3-cylinder at (0.5, 0.75)). The numerical investigation employs the penalty finite element technique to simulate the Darcy-Brinkmann-Forchheimer-based mathematical model. Moreover, the complete results of streamlines, isotherms, mean Nusselt number (Nu
m
), and thermal enhancement percentage (
En
%
) are analyzed at the broad range of flow parameters, including Rayleigh number (
Ra
=
(
10
3
−
10
6
)
), Darcy number (
Da
=
(
10
−
5
−
10
−
2
)
), and porosity value (
ϵ
=
(
0.1
−
0.9
)
). Initial comparative investigations of different configurations (C0-C3) at selected Ra values reveal that case C1 exhibits significant potential for enhancing convective heat transport phenomena. Consequently, only case C1 physical domain has been explicitly analyzed for convective heat and fluid flow characteristics at the selected range of flow parameters. Further, it is analyzed that the increasing range of Ra, Da, and ϵ enhances the convective heat and fluid flow phenomena. Furthermore, the comparative study of Nu
m
and
En
%
for case C1 against the simple case C0 reveals substantial improvements as Ra, Da, and ϵ increase. The
En
%
for Da and Ra reaches up to 97%, while a maximum of 25% improvement is observed with varying values of ϵ. These findings highlight the promising opportunities to optimize convective thermal transport in the investigated system, mainly through adopting case C1.
In this paper, statistical models were developed to investigate effect of cutting parameters on surface roughness and root mean square of work piece vibration in boring of stainless steel. A mixed ...level design of experiments was prepared with process variables of nose radius, cutting speed and feed rate. According to design of experiments, eighteen experiments were conducted on AISI 316 stainless steel with PVD coated carbide tools. Surface roughness, tool wear and vibration of work piece were measured in each experiment. A laser Doppler vibrometer was used to measure vibration of work piece in the form of acousto optic emission signals. These signals were processed and transformed in to different frequency zones using a fast Fourier transformer. Analysis of variance was used to identify significant cutting parameters on surface roughness and root mean square of work piece vibration. Predictive models like response surface methodology, artificial neural network and support vector machine were used to predict the surface roughness and root mean square of work piece vibration. Cutting parameters were optimized for minimum surface roughness and root mean square of work piece vibration using a multi response optimization technique.
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