Yunus Cengel

Bio: Yunus Cengel is an academic researcher. The author has an hindex of 1, co-authored 1 publications receiving 199 citations.

Thermodynamics : An Engineering Approach, 7th Edition

Abstract: Thermodynamics: An Engineering Approach 3rd edition by Cengel and Boles; Heat Transfer: A. Practical Approach by Cengel; Thermodynamics. 6th edition by Thermodynamics: An Engineering Approach, 6th Edition, McGraw Hill, 2007. Yunus A. Cengel and Michael A. Boles Thermodynamics: An Engineering . Thermodynamics: An Engineering Approach, 7th Edition Explain the basic concepts of thermodynamics such . solution of engineering problems and it. OBJECTIVES: 1. To develop a conceptual understanding of the fundamental elements of "Thermodynamics, An Engineering Approach", 7th Edition. . "Fundamentals of Engineering Thermodynamics, 6th Edition, Copyright 2008; Michael J..

An optimization algorithm inspired by the States of Matter that improves the balance between exploration and exploitation

Abstract: The ability of an Evolutionary Algorithm (EA) to find a global optimal solution depends on its capacity to find a good rate between exploitation of found-so-far elements and exploration of the search space. Inspired by natural phenomena, researchers have developed many successful evolutionary algorithms which, at original versions, define operators that mimic the way nature solves complex problems, with no actual consideration of the exploration-exploitation balance. In this paper, a novel nature-inspired algorithm called the States of Matter Search (SMS) is introduced. The SMS algorithm is based on the simulation of the states of matter phenomenon. In SMS, individuals emulate molecules which interact to each other by using evolutionary operations which are based on the physical principles of the thermal-energy motion mechanism. The algorithm is devised by considering each state of matter at one different exploration---exploitation ratio. The evolutionary process is divided into three phases which emulate the three states of matter: gas, liquid and solid. In each state, molecules (individuals) exhibit different movement capacities. Beginning from the gas state (pure exploration), the algorithm modifies the intensities of exploration and exploitation until the solid state (pure exploitation) is reached. As a result, the approach can substantially improve the balance between exploration---exploitation, yet preserving the good search capabilities of an evolutionary approach. To illustrate the proficiency and robustness of the proposed algorithm, it is compared to other well-known evolutionary methods including novel variants that incorporate diversity preservation schemes. The comparison examines several standard benchmark functions which are commonly considered within the EA field. Experimental results show that the proposed method achieves a good performance in comparison to its counterparts as a consequence of its better exploration---exploitation balance.

Fast hydrothermal liquefaction of a Norwegian macro-alga: Screening tests

Abstract: article i nfo Hydrothermal liquefaction of sugar kelp Laminaria saccharina, a brown macro-alga harvested in Trondheim bay (Norway), was experimentally studied by a high-throughput screening technique using sealed quartz capillary reactors. Very high heating rates were achieved by the experiment technique, which significantly intensified the liquefaction and resulted in much higher bio-oil yields. The highest bio-oil yield of 79% w (dry and ash free) was obtained from the test at the highest heating rate of 585 °C/min (temperature = 350 °C, holding time = 15 min, and kelp/water ratio = 1/10 w/w). The HHV of the bio-oil was also significantly improved, being as high as of 35.97 MJ/kg (dry and ash free). In addition, a numerical prediction and modelling supported by regression analyses showed a good agreement between the present study and the literature, with respect to the effect of heating rate on the bio-oil yield.

Performance Analysis and Components Irreversiblities of a (25 MW) Gas Turbine Power Plant Modeled with a Spray Cooler

Abstract: In this study the effect of inlet air cooling system and components irreversibilities on the performance of an active 25MW gas turbine power plant was investigated. The objective of this study was to establish the potential benefits of improving the performance of the current gas turbine plant into a more advanced cycle with high efficiency and power output through inlet air cooling. Problem statement: The hypothesis was that the low performance of the gas turbine plant was caused by high ambient temperature, the use of spray cooler was adopted to bring the air condition temperature close to ISO condition. Approach: In this study, performance characteristics were determined for a set of actual operational conditions including ambient temperature, relative humidity, turbine inlet temperature and pressure ratio. Results: The results obtained show that the use of a spray cooler on the existing gas turbine cycle gives a better thermal efficiency and less irreversibility rate in the components system and the entire plant. The power output of the gas turbine plant with spray cooler was found to have increased by over 7%, accompanied by 2.7% increase in machine efficiency with a reduction in specific fuel consumption of 2.05 and 10.03% increase in the energy of exhaust. Furthemore, a 0.32% reduction in the total irreversibility rate of the plant for the cooled cycle was obtained and a 0.39, 0.29 and 0.17% reduction in the irreversibility rate of compressor, turbine and combustion chamber respectively, were also obtained. Conclusion: The results show that retrofitting the existing gas turbine plant with inlet air cooling system gives a better system performance and may prove to be an attractive investment opportunity.