In this paper, the findings of boiler house efficiency improvement study carried out in a large boiler house unit of a pulp and paper mill has been presented. The causes of poor boiler efficiency were various heat losses such as loss due to unburnt carbon in refuse, loss due to dry flue gas, loss due to moisture in fuel, loss due to radiation, loss due to blow down, and loss due to burning hydrogen, etc. The various heat losses were analyzed and a set of recommendations were made to the plant management for implementation, so that efficiency of boiler can be increased. Five important recommendations were implemented by plant management, and it has been seen that there is tremendous increase in boiler efficiency. Economic analysis reveals that the expenditure on the proposed system will be recovered in a short span of time. This work, with only five recommendations implemented, has resulted in net increase of 2% in overall boiler efficiency and an annual saving of Rs. 34,12,395. In addition, it is observed that carefulness in the operation of boiler can help a great deal in energy efficiency improvement in boiler.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Sometimes the line of action of the load does not pass through the axis of a bearing and is shifted on either side by a few degrees. The effect of load orientation on the stability of a three-lobe pressure dam bearing has been studied in this article. A three-lobe pressure dam bearing is produced by incorporating two pressure dams in the upper lobes and a relief track in the lower lobe of an ordinary three-lobe bearing. The results show that the stability of a three-lobe pressure dam bearing supporting either rigid or flexible rotor is increased for the positive values of load orientation, that is, when the load line is shifted in the opposite direction of rotation.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

In this article, a fuzzy inference-based method for short-term load forecasting has been presented. Load data from European Energy Exchange has been selected for the case study. The "time," "temperature," and "historical load" are taken as inputs for the fuzzy logic controller and the "forecast load" is the output. Each of the input variables "time" and "temperature" has been divided into 7 triangular membership functions, whereas the input variable "historical load" has been divided into 10 triangular membership functions. The "forecast load" as output has been divided into 10 triangular membership functions. Then, 1 day ahead load forecast for each hourly interval has been performed using fuzzy logic method. Furthermore, performance of the fuzzy logic model is compared with a conventional model. It has been shown that the proposed method possesses better forecasting abilities than the other model.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

[FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

This article presents the theoretical investigations of the rheological effects of the lubricant on the performance of asymmetric slot-entry hybrid journal bearing system. Finite element method (FEM) has been used to solve the Reynolds equation governing the flow of lubricant in the bearing clearance space along with the restrictor flow equation. The non-Newtonian lubricant has been assumed to follow the cubic shear stress law. The simulated results of bearing characteristics parameters in terms of minimum fluid film thickness and bearing flow have been presented for the wide range of values of nonlinearity factor and external load. The computed results reveal that the variation of viscosity due to non-Newtonian behavior of the lubricant affects the performance of slot-entry hybrid journal bearing system quite significantly.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

A performance study of a 3-phase symmetric Cockcroft-Walton (CW)-multistage voltage multiplier (VM) is proposed. It consists of 1 smoothing column and 6 oscillating columns. The oscillating columns are connected to a 3-phase power through center-tap transformers. The capacitors of the smoothing column are charged 6 times per cycle by 6 oscillating columns and are discharged 6 times through the load, unlike the conventional symmetric VM in which they are charged and discharged twice per cycle. The 3-phase symmetric structure completely eliminates the first 5 harmonic components of load-generated voltage ripple. Theoretic analysis indicates that the proposed 3-phase symmetric CW-VM has one-third the voltage ripple and voltage drop of the conventional single-phase symmetric CW-VM. Simulation results of the proposed 3-phase symmetric CW-VM as well as those of the conventional single-phase symmetric CW-VM are presented. A comparison shows that the 3-phase symmetric CW-VM has significantly less voltage ripple, half the voltage drop, and a 4-fold increase in the output power over the conventional single-phase symmetric CW-VM.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Reinforced cement concrete (RCC) framed structures combined with shear walls have been widely used to resist lateral forces during earthquakes in tall buildings. Shear walls are generally provided for full height of the frames. Lateral forces are carried mostly by frames in the upper portion of the building and shear walls contribute the least in this region. This concept has been extended to 10, 20, and 30 storeyed symmetric RCC buildings with curtailment of shear walls at various heights. Efforts have been made to study the effect of height on the curtailment of shear wall. Three-dimensional models of RC special moment resisting frames have been analyzed using STAAD-Pro (Research Engineers, USA, 2005) software. The results show that curtailment of shear wall up to 50% height of the building, has a marginal effect on the distribution of horizontal storey shear among the shear wall frames and interior frames. But height of the building has a significant role in storey shear distribution.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Scour around bridge elements found in erodible sediment beds have always been a topic of interest for investigators on the subject. An insight into the mechanism of flow modification responsible for initiating and continuing the process of scour is the only way to understand and curb this undesirable hydraulic phenomenon. In this article, results of an experimental work on initiation and propagation of a vortex in the wake zone of a wing wall type abutment model are presented. Hydrogen bubble flow visualization technique is used for observing the vortex, and photographs for the initiation, strengthening, and diffusion of wake vortex are presented and discussed in a sequential manner.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

This article presents the application of Artificial Neural Network (ANN) for steady state monitoring of a power system. In steady state monitoring of a power system, it is important to predict the line flows and bus voltages for different operating conditions. In this article ANN has been proposed as an alternative method to solve the power system problems where the desired speed has not been achieved by conventional methods. The proposed method describes an adoptive pattern recognition approach based on highly parallel information processing. We provide a pattern of system description parameters to a neural network and net returns an estimate of line flows and bus voltages. Training data were obtained by Newton Rapson load flow simulation using Mipower Software Simulation Package for different system topologies over a range of load levels and the results were compiled to form the training data set. A back propagation algorithm was used for training ANN. Results of this approach help the power system operator to successfully handle the topologically independent steady state security assessment. To illustrate the proposed approach, IEEE-14 Bus system was considered. The difference between the actual and the estimated power flows and bus voltages was found to be good in terms of accuracy.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

Just in Time (JIT) is viewed in terms of elimination of waste or non-value-added activities. JIT as a management philosophy can be applied not only in manufacturing industries but also in the service sector. This article gives a useful insight into the applicability of JIT in the education sector by a survey of 25 institutes in Northern India. JIT takes a lot of time to be fully implemented in an organization. This article highlights the importance of some of the JIT elements, such as housekeeping, training and development, process simplification, administrative efficiency, to get the maximum utilization of all these.

[ABSTRACT]  [FULL TEXT]  [PDF]  [Mobile Full text]  [EPub] [CITATIONS]

[FULL TEXT]  [PDF]  [Mobile Full text]  [EPub]