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The present work reports the measurement of the laminar burning velocity for n-propanol and air mixtures at 1 atm pressure, with the unburnt mixture temperature varying up to 620 K using externally heated mesoscale diverging channels. Planar flames were stabilized in quartz channels using an externally heated mesoscale diverging channel to create a positive temperature gradient along the direction of fluid flow. The laminar burning velocity was extracted using the mass conservation principle at the flame surface and channel inlet. The performance of six recent kinetic mechanisms was evaluated through a comparison of the predictions to present experimental results. A significant disagreement (≈22%) was observed between different mechanism predictions, even at lower mixture temperatures of 335 K. The temperature exponent, α, was extracted using power-law correlations and observed to follow an inverted parabolic pattern with a minimum at a slightly rich equivalence ratio of 1.1, similar to other alcohol fuels.

In the deregulated power system, transmission pricing has become a very important task because it is necessary to develop an efficient, feasible and reliable pricing scheme that can generate the useful economic signals to transmission network users such as generating companies, distribution companies and customers. In a pool based market or bilateral contract market a number of techniques have been proposed to allocate the usage cost and loss cost of the transmission system to generators and/or loads under base case and contingency condition. In this paper, a new approach to allocate the usage cost and loss cost under contingency condition is presented. Maximum flow during an outage is calculated with the help of various line outage impact factors, then with the help of MW-Mile methodology, transmission usage cost and loss cost is allocated to users (generators and/or loads). Two test systems have been considered to check the efficiency and feasibility of the method namely Sample 6 and a large New England 39 bus system.

The dispatch problem has received considerable attention in the context of large as well as micro grids, especially in the presence of renewable resources and storage. The preferred approach of using model predictive control (MPC) for dispatch is computationally complicated by the presence of complex intertemporal constraints. This paper uses recent advancements in MPC and approximate dynamic programming to improve the computational efficiency of the approach. Specifically, the paper focuses on the design of terminal cost function on the MPC problem. The relative value function of a related problem with average cost criterion is proposed as the terminal cost and demonstrated to save significant computational efforts.

In this article, the optimal gain value of classical controller gain values is obtained by using different performance indices in Automatic Generation Control. These are interconnected by the three areas of a hydro-thermal power system. The thermal and hydro areas are incorporated with a reheat turbine and a mechanical governor, respectively. The current article was created to select a suitable technique for the tuning of controller gain, when 1% of a step load is given to the thermal area (Area 1). The performance of several controllers, such as Integral (I), Proportional-Integral (PI), and Integral-Derivative (ID) were evaluated and were compared to the cases of with and without Generation Rate Constraint (GRC) non-linearity. The classical controller gain value optimization was performed using the Integral Time Square Error (ITSE), Integral Square Error (ISE) and Integral Time Absolute Error (ITAE) performance indices. The minimum optimal value of controller gain normally offers better dynamic response. The obtained results established that the optimization based on the ITAE-PI controller always guarantees superior dynamic performances compared to other indices and controllers.

In this paper, beginning with a concise overview of the Available Transfer Capability (ATC) evaluation methods, we make a proposition for reliability management in the planning horizon of deregulated power systems through the concept of Adequacy Resiliency. The derived indices are meant as indicators of adaptability of power systems to ensure the required reliability levels. Improvements to this conceptualization upon the deployment of Flexible AC Transmission System (FACTS) devices are then put forward. We also explore the option of employing the created indices to the operational horizon of power systems, explaining the means of market enhancement. Core reliability issues arising out of the usage of FACTS are then discussed.

The aim of this paper is to develop a method based on combination of Empirical Mode Decomposition (EMD) and Hilbert Transform for assessment of power quality events. A distorted waveform can be conceived as superimposition of various oscillating modes and EMD is used to separate out these intrinsic modes known as intrinsic mode functions (IMF). Hilbert transform is applied to first three IMF to obtain instantaneous amplitude and phase which are then used for constructing feature vector. The work evaluates the detection capability of the methodology and a comparison with S-Transform is made to show the superiority of the technique in detecting the PQ disturbance like voltage spike and notch. A Probabilistic Neural Network is used as a mapping function for identifying the various disturbance classes. Results show a better classification accuracy of the methodology.

Thermal and chemical characteristics of the flames obtained from an industrial size regenerative combustion furnace have been obtained spectroscopically. The combustion characteristics of diffusion or premixed flames in the regenerative high-temperature air combustion facility have been examined using coal gas as the fuel. The fuel gas composition consisted of H2, hydrocarbon, CO, and N2. Monochromatic images of the flames have been observed in the emission mode using a CCD camera fitted with an optical band pass filter at the desired wavelength. The two-dimensional temperature distribution in the furnace has been determined using the two-line method by utilizing the Swan emission bands from within the flame. The emission intensity profiles of NO, as well as OH and CH radicals have also been observed spectroscopically. The results showed quite uniform two-dimensional temperature distribution and emission intensity of OH and CH radical species for the diffusion flame case as compared to the premixed case using high-temperature combustion air. The premixed flame case showed high local values and large fluctuations in the combustion zone for both emission intensity and temperature distribution. The temperature distribution of soot particles in the premixed flame was also determined using the two-color optical method. The results showed high local value of temperature, similar to that found for the gas temperature using signatures for C2 species at two different wavelengths. In contrast the distribution of temperature for soot particles was different. The location of the maximum soot temperature shifted to downstream positions of the flame as compared to the maximum gas temperature regions measured from the C2 species. The experimental results are discussed in conjunction with those obtained from the heat simulation analyses.

The study focused on the ability of firms to play this role is in major part determined by the structure of the financial system in which they operate, and in particular whether this financial system is able to make capital available efficiently to those firms that need it. The study examines the relation between the Financing, Investments, Capital Budget and Dividend decisions, where the effect of financial constraints on the firm’s investment decision is investigated. The study focuses on how financial constraints affect different firms by investigating the extent to which the dependence on internal cash flow is affected by firm characteristics such as size, age, dividend payout ratio, and market listing. This implies that firms retain earnings (RE) in order to ensure that they have sufficient capital to invest, confirming the initial result that Indian firms are financially constrained. This study adopted a descriptive design that aims at exploring the financial constraints of dividend policy and capital structure theories of companies listed at NSE and BSE in India. The data was obtained from financial statements and balance sheet of all the listed companies’ information available at the NSE and BSE secretariat for 10 years from 2005 to 2015.

Abstract In this study, dimethyl adipate, an organic ester, as the phase change material (core) was microencapsulated into melamine-formaldehyde (shell) in different shell-to-core ratios using in-situ polymerization technique. The microencapsulated phase change material suspensions (MPCMS) were prepared through the dispersion of microcapsules in appropriate proportions into the carrier fluid. The surface morphology of the prepared microcapsules were observed to be almost spherical. The microcapsules with low crystallinity offered greater resistance towards crack, which was attributed to the flexible structure of the shell. Surface structure studies has confirmed the chemical stability between the core and shell. In addition, the microcapsules exhibited good latent heat enthalpy of around 53 kJ/kg and 70 kJ/kg and they were thermally stable up to 160 °C. Furthermore, the viscosity of MPCMS was found to be very low, which enabled them to exhibit Newtonian flow behaviour. Thus, the test results have signified the MPCMS to be considered as a viable candidate for cool thermal energy storage application.