A project has been underway at the Dublin Institute of Technology (DIT) to investigate the feasibility of a combined Otto and Stirling cycle power plant in which a Stirling cycle engine would serve as a bottoming cycle for a stationary Otto cycle engine. This type of combined cycle plant is considered to have good potential for industrial use. This paper describes work by DIT and collaborators to validate a computer simulation model of the combined cycle plant. In investigating the feasibility of the type of combined cycle that is proposed there are a range of practical realities to be faced and addressed. Reliable performance data for the component engines are required over a wide range of operating conditions, but there are practical difficulties in accessing such data. A simulation model is required that is sufficiently detailed to represent all important performance aspects and that is capable of being validated. Thermodynamicists currently employ a diverse range of modeling, analysis and optimization techniques for the component engines and the combined cycle. These techniques include traditional component and process simulation, exergy analysis, entropy generation minimization, exergoeconomics, finite time thermodynamics and finite dimensional optimization thermodynamics methodology (FDOT). In the context outlined, the purpose of the present paper is to come up with a practical validation of a practical computer simulation model of the proposed combined Otto and Stirling Cycle Power Plant.
A STUDY on the extent of heroin use in a Dublin *^ South Inner City Electoral Ward during the period 1979-1985 was conducted between May and September. A total of 82 questionnaires were completed. Each respondent had a settled address in the Ward during 1979-1985. All gave a history of heroin use. The authenticity of heroin use was validated for all respondents through medical records. The extent of heroin use in the area was greatest in the 1979-1981 period and during this time it was concentrated in the under 25 year age groups, particularly males 15-19 years old. Since 1981 there has been a marked decline in heroin use within the Ward. The profile of the heroin user is similar to that described in previous Medico-Social Research Board studies.
The generation of electrical and thermal power is a matter of critical importance to the modern world. Considerable quantities of both power types are required in all sectors of society; industrial, domestic and leisure, with the future prosperity of both developed and developing societies being dependant on generation of both a sufficient quantity and quality of power. Central to this discussion on the international front is the topic of fossil fuel usage. Despite considerable advances in renewable energy conversion technologies, the human race remains dependant on fossil fuels as a primary energy source. With increasing demand for these finite resources giving rise to strained international relations and economic uncertainty, emphasis has fallen on optimization of usage patterns. The area of power plant efficiency is essential to this optimization. This paper proposes a method for increasing the efficiency of an Otto cycle engine based plant as is typically used in CHP and other Distributed Generation scenarios. The method proposed is to utilise a Stirling cycle engine as a heat recovery device on the exhaust stream of the Otto engine. Thermal energy that may otherwise be lost would thereby be recovered and used to generate additional electrical power. In this manner energy is effectively diverted from the exhaust flow of the engine and converted to mechanical work by way of the Stirling cycle engine. It is postulated that this combined cycle will yield higher plant efficiency than the Otto engine alone. This paper introduces work completed to date and an experimental plan for the project. The project was initiated at undergraduate level as a feasibility study for application of the hybrid engine in automotive circumstances. The study suggested that the combination of the engines in the proposed manner was indeed feasible, with significant power gains possible. However, it proved unlikely that automotive application was the best use of the system unless certain constraints were addressed. Therefore, it was decided to pursue the concept in terms of a stationary generation system. The advantages of the stationary system over the automotive system are addressed briefly, with the constraints of the automotive scenario analysed and their relevance to the stationary generation situation examined. The central areas under investigation are detailed, including thermodynamic theory pertaining to the Otto cycle and Stirling cycle engines, and the combined cycles. Possible limiting factors to the design are discussed also.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with đŸ’™ for researchers
Part of the Research Solutions Family.