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An aerosol rapid compression machine is developed to investigate energetic-nanoparticleenhanced combustion of liquid fuels using ethanol and aluminum nanoparticles as a model system. An ultrasonic nozzle is used to nebulize neat ethanol and mixtures containing nanoparticles for ignition delay tests in the rapid compression machine. It is determined that 2%-weight nano-aluminum can lead to a dramatic reduction in the ignition delay (90%). The aerosol is introduced to the rapid compression machine through a poppet valve that is optimized by CFD simulations to maximize turbulent mixing and...
The transport industries face a continuing demand from customers and regulators to improve the acoustic performance of their products: reduce noise heard by passengers and passersby; avoid exciting structural modes. In both the aerospace and automotive areas, flow-induced noise makes a significant contribution, leading to the desire to understand and optimize it through the use of simulation. Historically, the need for time-consuming, computationally expensive transient simulations has limited the application of CFD in the field of acoustics. In this paper are described efficient simulation...
The transport industries face a continuing demand from customers and regulators to improve the acoustic performance of their products: reduce noise heard by passengers and passersby; avoid exciting structural modes. In both the aerospace and automotive areas, flow-induced noise makes a significant contribution, leading to the desire to understand and optimize it through the use of simulation. Historically, the need for time-consuming, computationally expensive transient simulations has limited the application of CFD in the field of acoustics. In this paper are described efficient simulation...
The CFD simulation of diesel combustion needs as accurate initial values as possible to be reliable. In this paper the effect of spatial distribution of state and turbulence values at intake valve closure to those distributions prior to SOI is studied.Totally five cases of intake and compression stroke simulations are run. The only change between cases is the intake boundary condition of turbulence. In the last case the average values of p, T, k, ε and swirl number at intake valve closure are used as initial values to compression simulation.The turbulence in the engine cylinder is mainly...
Detailed computational fluid dynamics models of mineral insulated metal sheath thermocouples are discussed, and thermocouple readings in clean flames are verified against experimental thermocouple data for a Hencken burner flame available in the literature. Computational results present thermocouple temperature readings as a function of thermocouple insertion depth in threedimensional directions. Computational temperature correlations are plotted against nondimensional insertion depth and insertion height above the burner. Overall predictions showed excellent agreement with experimental data...
Three-dimensional numerical computations have been carried out to investigate the dynamics inside proton-exchange membrane fuel cell (PEMFC) and its performance using STAR-CD solver, the computational fluid dynamics software. Theoretical results in polarization curves quantitatively corroborate the experimental findings previously reported in Jung et al. Also, effects of various process conditions such as relative humidity, stoichiometric ratio at anode and cathode channels, and cell configuration on the performance of fuel cell have been further scrutinized. It has been revealed that the...
Two different medium-speed diesel engine cylinder head designs have been studied. The focus of the study has been the effect of intake channel design in the in-cylinder flow. The study has been carried out by CFD. The first cylinder head is a standard Wärtsilä 20 cylinder head and the second one is a specially designed head for a single cylinder research engine, called Extreme Value Engine (EVE). The CFD boundary conditions have been simulated by the help of a 1-d simulation code. In the full load cases the maximum cylinder pressure was 300 bar. Simulations have been done at lower load level...
In order to increase engine capacity of close-deck single-bore type engine blocks, bore diameter is usually enlarged that results in thinner intra-bore sections. Enlarged intra-bore sections affect thermal loads around the cylinders as well as manufacturing complexities due to thinner water jacket cores. As a possible remedy, intrabore cores can be removed and passages can be created in the intrabore region by multiple drills. However, it should be ensured that sufficient heat transfer from ring reversal area is possible and effect on bore distortion is acceptable. The second item is...

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