10 Engines (power generation and propulsion, electrical vehicles) maximum ecological function, are determined. It is shown that both the power output and entropy-generation rate are increased significantly by the use of regenerators, and increase monotonically with an increase with hot/cold temperature ratio. The results further indicate that the thermal efficiency and exergetic efficiency are decreased by the use of regenerators and rise with an increase in the temperature ratio. By the introduction of the ecological function, the improvements in exergetic efficiency and thermal efficiency are evident.
NOx emission from the fully loaded diesel engine fuelled with the treated shale oil reduces by 29.1% (SO-2E) and 23.0% (Marisol FT). It is important that the lower NOx is obtained due to reducing both harmful pollutants, NO and NO2. The CO emission at rated power increases by 16.3% (SO-2E) and 48.0% (Marisol FT), whereas the smoke opacity of the exhausts increases by 35% and over two times, respectively. The effect of the fuel additives on the HC emission seems to be complicated and ambiguous.
05/02693 Fuzzy control with random delays using invariant cones and its application to control of energy processes in microelectromechanical motion devices Sinha, A. S. C. and Lyshevski, S. Energy Conversion and Management, 2005, 46, (7-8), 1305-1318. In this paper, a class of micro-electromechanical systems described by non-linear differential equations with random delays is examined. Robust fuzzy controllers are designed to control the energy conversion processes with the ultimate objective to guarantee optimal achievable performance. The fuzzy rule base used consists of a collection of fuzzy IF-THEN rules defined as a function of the conditional variable. The method of the theory of cones and Lyapunov functionals is used to design a class of local fuzzy control laws. A verifiably sufficient condition for stochastic stability of fuzzy stochastic micro-electromechanical systems is given. As an example, the study considered the design of a fuzzy control law for an electrostatic micro-motor.
05•02697 On line protection systems for induction motors ~olak, I. et al. Energy Conversion and Management, 2005, 46, (17), 2773-2786. Protection of induction motors is very important since they are widely used in industry for many applications due to their high robustness, reliability, low cost and maintenance, high efficiency and long service life. So, protecting these motors is crucial for operations. This paper presents a combined protection approach for induction motors. To achieve this, the electrical values of the induction motor were measured with sensitivity :k1% through a data acquisition card and processed with software developed in Visual C+ +. An on line protection system for induction motors was achieved easily and effectively. The experimental results have shown that the induction motor was protected against the possible problems faced during the operation. The software developed for this protection provides flexible and reliable media for operators and their motors. It is expected that the motor protection achieved in this study might be faster than the classical techniques and also may be applied to larger motors easily after small modifications of the software.
05/02694 Humidified gas turbines - a review of proposed and implemented cycles Jonsson, M. and Yan, J. Energy, 2005, 30, (7), 1013-1078. Gas turbines with air-water mixtures as the working fluid promise high electrical efficiencies and high specific power outputs to specific investment costs below that of combined cycles. Different humidified gas turbine cycles have been proposed, for example direct waterinjected cycles, steam-injected cycles and evaporative cycles with humidification towers. However, only a few of these cycles have been implemented and even fewer are available commercially. This paper comprehensively reviews the literature on research and development on humidified gas turbines and identifies the cycles with the largest potential for the future. In addition, the remaining development work required for implementing the various humidified gas turbine cycles is discussed. This paper can also be used as a reference source that summarizes the research and development activities on humidified gas turbines in the last three decades. 05/02695 Hybrid fuzzy controller for speed control of switched reluctance motor drives Paramasivam, S, and Arumugam, R. Energy Conversion and Management, 2005, 46, (9-10), 1365-1378. A hybrid fuzzy controller for speed control of switched reluctance motor (SRM) drives is presented in this paper. The developed hybrid fuzzy control law consists of a proportional integral (PI) controller at steady state, a PI type fuzzy logic controller (FLC) at transient state and a simple logic controller between the steady and transient states to achieve the desired performance at various operating conditions under soft chopping operation. The importance of the hybrid fuzzy controller is highlighted by comparing the performance of various control approaches, including PI control, PI type fuzzy logic control and PD type fuzzy control for speed control of SRM motor drives. The complete control algorithm is demonstrated by intensive experimental results. It is shown that the presented hybrid controller for SRM drive has fast tracking capability, less steady state error and is robust to load disturbance. The complete speed control scheme of the SRM drive incorporating the hybrid control is experimentally implemented and validated using a high speed digital signal processor board TMS320F2812 for a prototype 1.2 kW SRM. 05•02696 Influence of fuel additives on performance of direct-injection Diesel engine and exhaust emissions when operating on shale oil Labeckas, G. and Slavinskas, S. Energy Conversion and Management, 2005, 46, (11-12), 1731-1744. The article presents the comparative bench testing results of a naturally aspirated four stroke, four cylinder, water cooled, direct injection diesel engine when running on shale oil that has been treated with multi-functional fuel additives. The purpose of the research is to evaluate the ,effectiveness of the fuel additives Marisol FT (Sweden) and SO-2E (Estonia) as well as to verify their ability to increase energy conversion and reduce brake specific fuel consumption, contamination and smoke opacity of the exhausts when fuelling the diesel engine with shale oil. Test results show that application of these additives could be a very efficient means to improve diesel engine performance on shale oil, especially when operating at the light load range. The brake specific fuel consumption at light loads and speeds of 1400-2000 rain 1 reduces by 18.3-11.0% due to the application of the Marisol FT. The additive SO-2E proves to produce nearly the same effect. The total
05/02698 Performance characteristics of a Diesel engine power plant Kanoglu, M. et al. Energy Conversion and Management, 2005, 46, (1112), 1692-1702. Performance of an actual Diesel engine power plant with a rated output of 120 MW is analysed based on the first and second laws of thermodynamics. The plant consists of seven identical Diesel engines and various subsystems including turbochargers, fuel heating units and heat exchangers performing various useful tasks. The engine runs on heavy fuel oil, and the pollutant emissions from the engine are greatly reduced by effective treatment systems. The characteristics and performance parameters of the internal combustion engines of the plant are evaluated. The mass, energy and exergy balances are verified for each flow stream in the power plant. The work and heat interactions, the exergy losses and the efficiencies of various components based on both energy and exergy concepts are evaluated. The thermal and the exergy efficiencies of the plant are determined to be 47% and 44%, respectively. The engine irreversibilities are due mostly to the irreversible combustion process and account for 32% of the total exergy input and 57% of the total irreversibilities in the plant. Most of the remaining irreversibilifies in the plant occur in the desulphurization, intercooler, compressor and lubrication oil cooler units. The results should provide a realistic and meaningful ground for the performance evaluation of Diesel engine power units, and it may be used in the design and analysis of such systems. 05/02699 Study on the design of inlet and exhaust system of a stationary internal combustion engine Kesgin, U. Energy Conversion and Management, 2005, 46, (13-14), 2258-2287. The design and operational variables of inlet and exhaust systems are decisive to determine overall engine performance. The best engine overall performance can be obtained by proper design of the engine inlet and exhaust systems and by matching the correct turboeharger to the engine. This paper presents the results of investigations to design the inlet and exhaust systems of a stationary natural gas engine family. To do this, a computational model is verified in which zero dimensional phenomena within the cylinder and one dimensional phenomena in the engine inlet and exhaust systems are used. Using this engine model, the effects of the parameters of the inlet and exhaust systems on the engine performance are obtained. In particular, the following parameters are chosen: valve timing, valve diameter, valve lift profiles, diameter of the exhaust manifold, inlet and exhaust pipe lengths, and geometry of pipe junctions. Proper sizing of the inlet and exhaust pipe systems is achieved very precisely by these investigations. Also, valve timing is tuned by using the results obtained in this study. In general, a very high improvement potential for the engines studied here is presented. 05•02700 The air membrane-ATR integrated gas turbine power cycle: a method for producing electricity with low CO2 emissions Fiaschi, D. et al. Energy Conversion and Management, 2005, 46, (1516), 2514-2529. The air membrane-auto thermal reforming (AM-ATR) gas turbine cycle combines features of the R-ATR power cycle, introduced at the University of Florence, with ceramic, air separation membranes to Fuel and Energy Abstracts