dwell on the factors that preclude the attainment of ideal-performance of the system. Analysis based on the combined first and second law of thermodynamics commonly known as availability analysis or exergy analysis is particularly suited for achieving more efficient resource use since it enables the locations, types and true magnitudes of waste and loss to be determined. This information is quite helpful for the design of thermal systems, for directing the efforts to reduce the sources of inefficiency in the existing systems and evaluate system economics. [1, 2 & 3].
In thermodynamics, exergy is defined as the maximum theoretical work which can be obtained as the system comes to equilibrium with its reference environment. Unlike energy, exergy
…show more content…
The magnitude of exergy destruction is a quantitative measure of irreversibilities present in the system. Thus, the knowledge of the magnitude of exergy destruction and identification of the component where maximum exergy destruction occurs can be helpful in the better design of the equipment and selection of appropriate processes for minimizing losses.
Flynn et al. [4] studied a turbocharged, intercooled diesel engine using second law analysis to evaluate low-heat-rejection engine concepts. They were performed the simulation of engine cycle process. Primus and Flynn [5] reported a study demonstrating the benefits of using the second law in determining various energy losses in a diesel engine. Defining a thermodynamic system as outside the engine cylinder. Alkidas [6] applied energy and exergy balances to a diesel engine using experimental measurements. Shapiro and Van Gerpen [7] extended their earlier work to include a two-zone combustion model and applied this model to both a compression-ignition and a spark ignition engine. As before, their study included chemical exergy considerations. They presented the
…show more content…
Van Gerpen and Shapiro [10] performed a second law analysis of diesel engine combustion employing a standard cycle simulation Rakopoulos et al. [11] investigated the accumulation and destruction of exergy in a direct-injection diesel engine based on experimental data. Rakopoulos et al. [12] analyzed the multi-cylinder turbocharged diesel engine from a second law perspective, considering single zone thermodynamic model for combustion process. A comprehensive computer software was developed to simulate various process. Datta and Som [13] developed a theoretical model for exergy analysis, based on availability transfer and flow availability, in the process of spray combustion, to evaluate the total thermodynamic irreversibility. Caton [14] reviewed over two dozen previous studies that had investigated the operation of internal combustion engines using the second law of thermodynamics. C.D. Rakopoulos and D.C. Kyritsis [15] applied the first and second law analysis is used to calculate the rate of entropy production as a function of fuel reaction rate. In the modelling of engine, a three-hole
Driven in large part by global initiatives and the potential for stringent regulations, the past decade or two has seen a marked increase in the importance of improvements with respect to environmental standards, including emissions and increases in fuel economy. In 2002, Cummins Emissions Solutions was launched after the need was identified for an emission solution that would help engines meet future regulations. In 2006, Cummins pioneered a hybrid diesel-electric bus which reduced fuel consumption and greenhouse gasses by more than 30 percent and me...
...ese dangerously harmful gasses would be released into our atmosphere by all combustion engines. Although the catalytic converter when operating at its optimal temperature can break down over 95% percent of the harmful gasses produced by the engine it does not do a well at all when not at high temperatures. It takes about five miles of driving for most vehicles to reach a temperature at which the reactions will reach near completion, before this temperature the catalytic converter does practically nothing to convert these harmful gases. Some catalytic converters now have coils running from the engine to the catalytic converter to heat the catalytic converter to its optimal temperature soon after the engine has started to produce harmful gasses. With this improvement the catalytic converter can effectively reduce almost all of the carbon monoxide and nitrogen oxide.
The tradeoffs of using gasoline for cars are large emission of carbon dioxide and required large amount of chemical t...
After Diesel’s death, the diesel engine underwent much development and became a very important replacement for the steam piston engine in many applications. Because the diesel engine required heavier, more robust construction than a gasoline engine, it was not widely used in aviation. The diesel engine became widespread in many other applications, however, such as a stationary engines, submarines, ships, and much later, locomotives, trucks, and in modern automobiles. Diesel engines are most often found in applications where a high torque requirements and low RPM requirements exist.
Who would like to drive a car that gets worse gas mileage, a car that has less torque, and car that is all round mediocre? Now who would like to drive a car with much better gas mileage, higher torque, and a great, reliable engine? The obvious choice is the latter, a car with a diesel engine. Diesel and Gasoline engines have been each other’s competition since the 1930’s. There is one main mechanical difference between these two engines; a gasoline engine ignites the gasoline with spark plugs, a lighter of sorts, and the diesel engine ignites the diesel by compressing is so much that it spontaneously combusts. Although there are a few other types of engines now, such as hybrid or electric, diesel is still all round superior to these. I have
be yes as I will then be able to use enthalpy change of reaction to
The performance of the PEM fuel cell is evaluated by a thermodynamic analysis, which is of two types, viz., energy analysis and exergy analysis. The energy analysis is made by applying the first law of thermodynamics to the fuel cell. The efficiency is defined by considering the heat input to the fuel cell and the work output from the fuel cell. In the exergy analysis the fuel cell and the surrounding environment are considered together. The efficiency is defined based on the maximum or available energy which is calculated by considering the entropy lost to the environment. Thus the exergy analysis takes into account the second law of thermodynamics in addition to the first law. In this chapter a theoretical analysis
85% equipments use single-cylinder diesel engines, while the rest use multi-cylinder ones. In the market of multi-cylinder diesel the competition is less intense because of excessive demand. The prospect is much more promising. Longxi has a certain competitive advantage in this market, resulting from its popular product such as SL2100.
Energy can come in many different ways but not every way is good for the environment. By-products produced from the waste or energy being converted can cause harmful repercussions to the environment. There is more than 200 million tons of hazardous waste that is created annually through such things like pharmaceuticals, cosmetics, cleaning products, etc. (High Temperature Incineration, n.d.). I will be discussing the incineration process as well as the pros and cons of incineration based waste to energy have on the environment. I will also be going over my views on incinerating waste and what steps should be taken to get rid of waste more effectively. To better understand the positives and negatives about incineration technology the process
There are two main kinds of problems in internal combustion engine which contribute negatively in our life. These two problems are the emissions, which is related to the environment, and mechanical problems, which are related to the internal combustion engines themselves. In this project, the focus will be on some solutions for these two problems.
Sirignano, W. A., & Liu, F. (1999). Performance increase for gas-turbine engine through combustion inside the turbine. Journal of Propulsion and Power, 15(1), 111-118.
As in any application there is fluctuation in heat load, this fluctuation affects optimal values of efficiency which causes decrement in system's overall efficiency.
It started in 1880, when Rudolf went for the ferm of his professor named Karl Linde. It was then later in 1885 when he finished the design for his engine, an internal fire engine in which heat produced by the tightness of air in the cylinder is used to light the fuel. Diesel had read Sadie Carnot’s writings and it inspired Diesel so he published his own book called, “Theory and Design of a Rational Thermal Engine and the Combustion Engines Today,” (“Diesel Biography.)
This efficiency change can be enhanced in the condition where the system works with smaller NTU, higher isentropic efficiency,
In my undergraduate years, I have acquired a strong background in the fundamentals of basic mechanical engineering, having studied subjects such as Strength of Materials, Thermodynamics, Fluid Mechanics, Heat and Mass Transfer, Design of Machine Elements and Automobile Engineering. Whilst pursuing my diploma & degree courses, my interest for Automotive Engineering grew even more having learnt more on the different types of internal combustion engines, their configuration and importance. However, what I lacked was a practical understanding on these core areas of Automotive Engineering. To gain a better understandi...