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The objective of the work is to learn about the internal structure of transient evaporative Diesel sprays. A simple atomization model of a non-stationary evaporative spray, described in [1], is used in this paper to study the effects of the operating variables and atomization parameters, of the primary and secondary models, on the Diesel sprays characteristics. The model is a phenomenological and DDM one, and is realized in a PC with C programming language. There are several sub-models included: A primary atomization model of the jet liquid vein based on the jet interface instabilities caused by the aerodynamic action, including an intact length model. A secondary atomization model of droplets break-up based on the Taylor analogy. A droplet evaporation model including the heat-up and the stationary periods, as well as the natural and forced convection effects.

With the aim of accomplishing pollutant emissions policies, EGR-cooler has acquired an important role inside the whole EGR system in diesel engines. This paper presents a methodology to design and size EGR-coolers based on the integration of fluid-dynamic tools (CFD), specifically developed codes, experimental tools and a knowledge bank with previous experiences. Each different geometry of EGR-coolers (cooler family) requires an initial study through CFD, which allows the characterization of different thermo-fluid-dynamic variables. After that, correlations, related to heat exchange and pressure drop for the cooler family, are obtained from the CFD results and implemented in a fast-running one-dimensional code. This code lets size EGR-coolers with specific design characteristics and performance requirements of this family. An experimental tool carries out efficiency and pressure drop tests on EGR-cooler prototypes in order to validate the theoretical results.

An experimental procedure to determine the two components of the crankshaft force on the bearing cap is presented in this work. The method is based on the use of two load cells, one in each bearing cap bolt. A system to calibrate the force transference from the bearing cap to the load cells has been used. This system allows the calculation of the two components of the crankshaft forces as a function of the load cells signals. Some experiments have been done with this system, and the results of a firing and motored engine have been compared in order to know the influence of combustion and inertia forces on the crankshaft load in the bearing cap. The results are compared with a model for the dynamics of the piston-connecting rod-crankshaft system.

In this paper, models developed to determine exhaust emissions from Spark Ignition engines are shown. Concretely, a model based on chemical kinetics for determining CO and NOX emissions is presented. Also it is shown a model for the determination of the HC exhaust emissions based on retention in crevices, wall quenching, and in-cylinder and exhaust pipe post-flame combustion processes. Both models are included in a quasi-dimensional multizone model that permits the fast analysis and prediction of combustion in homogeneous-charge SI engines. Finally, results obtained from the models are compared with experimental exhaust emissions measured in a test bench.

The present study has been performed in order to characterize the compact plate-type heat exchangers that are used to cool the lubricating oil of Internal Combustion Engines. During the work an evaluation model has been developed for water/engine-oil heat exchangers. The evaluation model uses experimental data such as coolant and oil flow rates and the heat exchanger inlet and outlet temperatures. Also a predictive model has been developed, based on the application of the fluid flow and heat transfer equations of the real heat exchanger geometry. This model permits the performance calculation of the heat exchangers in arbitrary conditions. Simultaneously an experimental facility has been projected and built for testing the heat exchangers. The test facility allows to fix oil and coolant flow rates and temperatures over a wide range.