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Abstract A simple transient analysis of the conventional mud chullah of single pot seat has been presented. The effects of various parameters, namely pressure and non-pressure pot, use of insulation in walls and basement of the chullah, heat capacity of pot-water, burning rate of wood, and heat losses from the combustion gas, have been incorporated in the analysis. Keeping in view the outcomes of this analysis, some interesting recommendations have been made to make the mud chullah more efficient.

Abstract A simple transient analysis of the conventional mud chullah of single pot seat has been presented. The effects of various parameters, namely pressure and non-pressure pot, use of insulation in walls and basement of the chullah, heat capacity of pot-water, burning rate of wood, and heat losses from the combustion gas, have been incorporated in the analysis. Keeping in view the outcomes of this analysis, some interesting recommendations have been made to make the mud chullah more efficient.

This paper proposes a fuzzy based steam diversion valve to divert the steam to a storage tank during the occurance of a fault in a power system in order to improve stability of the system. The advantages of this technique over fast valving are discussed. The rate of opening and closing of valve are decided by the fuzzy controller. The valve operation is coordinated with fuzzy based braker. The technique is demonstrated for a single machine infinite bus system as well as four generators-ten bus multimachine system.

This paper proposes a fuzzy based steam diversion valve to divert the steam to a storage tank during the occurance of a fault in a power system in order to improve stability of the system. The advantages of this technique over fast valving are discussed. The rate of opening and closing of valve are decided by the fuzzy controller. The valve operation is coordinated with fuzzy based braker. The technique is demonstrated for a single machine infinite bus system as well as four generators-ten bus multimachine system.

Abstract This paper describes an experimental study on the effect of tube diameter on the mechanism of flooding in vertical gas–liquid countercurrent annular flow. Flooding experiments were conducted with three different tube inner diameters, namely, 25, 67 and 99 mm with smooth inlet and outlet conditions for air and water. The results indicate that the mechanism of flooding is qualitatively different in the small and the large diameter test sections. While flooding in the 25 mm diameter section occurred essentially by the upward movement of large waves created near the liquid outlet, no such waves could be seen in the 67 and the 99 mm diameter test sections. Here, flooding occurred by droplet carryover or by an unstable, churn-like motion in the liquid film. The results are compared with existing correlations. The effect of test section length on flooding was also investigated.

Abstract This paper describes an experimental study on the effect of tube diameter on the mechanism of flooding in vertical gas–liquid countercurrent annular flow. Flooding experiments were conducted with three different tube inner diameters, namely, 25, 67 and 99 mm with smooth inlet and outlet conditions for air and water. The results indicate that the mechanism of flooding is qualitatively different in the small and the large diameter test sections. While flooding in the 25 mm diameter section occurred essentially by the upward movement of large waves created near the liquid outlet, no such waves could be seen in the 67 and the 99 mm diameter test sections. Here, flooding occurred by droplet carryover or by an unstable, churn-like motion in the liquid film. The results are compared with existing correlations. The effect of test section length on flooding was also investigated.

Abstract A multiobjective thermal power dispatch problem is formulated using noncommensurable objectives such as operating costs and minimal emission. A sensitivity measure is chosen whereby the effects of variations in the nominal conditions describing a given multiobjective problem can be measured and incorporated as a performance index to be minimized. A nonlinear programming problem provides the framework for examining the objective constraint level in an ϵ-constant form of the multiobjective optimization problem. The dispersion index is chosen as the sensitivity measure for the investigation of the effects of random variations in the model parameters of the optimal solution. A sensitivity trade-off is exploited for the multiobjective problem that represents the trade-off between sensitivity and objective level. Validity of the method has been demonstrated by analysing a three-generator sample system.

Abstract A multiobjective thermal power dispatch problem is formulated using noncommensurable objectives such as operating costs and minimal emission. A sensitivity measure is chosen whereby the effects of variations in the nominal conditions describing a given multiobjective problem can be measured and incorporated as a performance index to be minimized. A nonlinear programming problem provides the framework for examining the objective constraint level in an ϵ-constant form of the multiobjective optimization problem. The dispersion index is chosen as the sensitivity measure for the investigation of the effects of random variations in the model parameters of the optimal solution. A sensitivity trade-off is exploited for the multiobjective problem that represents the trade-off between sensitivity and objective level. Validity of the method has been demonstrated by analysing a three-generator sample system.

ABSTRACT This paper presents a second order decoupled load flow method. The salient features are consideration of all terms in the Taylor series expansion, use of constant decoupled Jacobians and extremely simple computations involved in evaluating the active and reactive power mis-match vectors. Load flow solutions for several test systems have been obtained using the proposed and Fast Decoupled Load Flow (FDLF) methods. The test cases include systems with large R/X ratio transmission lines and series compensated lines.Limited investigations reveal that the proposed method has an edge over the FDLF method in terms of reliability of convergence and solution time.

ABSTRACT This paper presents a second order decoupled load flow method. The salient features are consideration of all terms in the Taylor series expansion, use of constant decoupled Jacobians and extremely simple computations involved in evaluating the active and reactive power mis-match vectors. Load flow solutions for several test systems have been obtained using the proposed and Fast Decoupled Load Flow (FDLF) methods. The test cases include systems with large R/X ratio transmission lines and series compensated lines.Limited investigations reveal that the proposed method has an edge over the FDLF method in terms of reliability of convergence and solution time.