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Influence of Secondary Flow Generation on Heat Transfer inside the Fin Type Spiral Sub-Cooled Condenser by Experimental and CFD Analysis

Sophia University-Hardeep Singh, Takashi Suzuki, Mitsuhisa Ichiyanagi
Keihin Corporation-Junya Washiashi, Jun Liu
Published 2018-10-30 by SAE International in United States
This paper discusses the compact structure, innovative and unique approach of high performance spiral coil sub-cooled condenser for compact power plant/engine applications. The motivation behind this study is to reduce the engine emission by improving the coefficient of performance for air-conditioning unit. Since the air conditioning system is the most power consumption units after the power plant, so it significantly affects the fuel consumption and the hazardous gas emissions. In the air condition cycle, the condenser unit is addressed as one of the important devices, and thus, the author tried to reduce the energy consumption by improving the performance of the condenser. The most advantage points of this study is to use spiral coil sub-cooled condenser, which elaborates the effect of secondary flow generation inside the fluid and is known as the Dean’s effect. This results in the heterogeneous temperature distribution across the periphery of the tube and lead to a greater heat transfer. The heat transfer characteristics for the tube-fin type with spiral coil and square cross-section have been determined experimentally and then compared…
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Modeling of Quasi-Steady State Heat Transfer Phenomena with the Consideration of Backflow Gas Effect at Intake Manifold of IC Engines and Its Numerical Analyses on 1-D Engine Simulation

Sophia University-Emir Yilmaz, Mitsuhisa Ichiyanagi, Takashi Suzuki
Published 2018-10-30 by SAE International in United States
An empirical equation was developed for modeling the heat transfer phenomena taking place in an intake manifold which included the backflow gas effect. In literature, heat transfer phenomenon at intake system is modeled based on steady flow assumptions by Colburn analogy. Previously, authors developed an equation with the introduction of Graetz and Strouhal numbers, using a port model experimental setup. In this study, to further improve the empirical equation, real engine experiments were conducted where pressure ratio between the intake manifold and engine cylinder were added along with Reynolds number to characterize the backflow gas effect on intake air temperature. Compared to the experimental data, maximum and average errors of intake air temperature estimated from the new empirical equation were found to be 2.9% and 0.9%, respectively. Furthermore, Colburn analogy and suggested empirical equation were consecutively implemented to 1-D engine simulation software on gasoline and diesel engine setups. Naturally aspirated gasoline engine simulations revealed the importance of the backflow gas effect in line with the real engine experiments. Maximum and average temperature differences between the…
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Modeling of Unsteady Heat Transfer Phenomena at the Intake Manifold of a Diesel Engine and Its Application to 1-D Engine Simulation

Sophia University-Emir Yilmaz, Hayao Joji, Mitsuhisa Ichiyanagi, Takashi Suzuki
  • Technical Paper
  • 2017-32-0097
Published 2017-11-05 by Society of Automotive Engineers of Japan in Japan
In the past two decades, internal combustion engines have been required to improve their thermal efficiency in order to limit hazardous gas emissions. For further improvement of the thermal efficiency, it is required to predict the mass of intake air into cylinders in order to control the auto-ignition timing for CI engines. For an accurate prediction of intake air mass, it is necessary to model the heat transfer phenomena at the intake manifold. From this intention, an empirical equation was developed based on Colburn equation. Two new arguments were presented in the derived formula. The first argument was the addition of Graetz number, where it characterized the entrance region thermal boundary layer development and its effect on the heat transfer inside the intake manifold. As the second argument, Strouhal number was included in order to represent intake valve effect on heat transfer. This study compared experimental data with the present empirical equation, and average error was estimated to be 3.1%, which was significantly improved in comparison with the Colburn equation. Furthermore, derived empirical heat transfer…
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Disturbance Estimation Based Modeling Technique for Control and Prediction in Controllable Mechanical Turbo-Compounding System

SAE International Journal of Passenger Cars - Electronic and Electrical Systems

Sophia University-Tielong Shen
Tianjin University-Zhengling Lei, Hui Xie
  • Journal Article
  • 2016-01-0023
Published 2016-04-05 by SAE International in United States
Modeling techniques matter a lot in many fields of engine engineering. Models are requested not only for control design but also for dynamic prediction. However, problems might be encountered during modeling process either because of the system complexity or the unaffordable modeling cost. As a result, a new modeling technique based on disturbance estimation is proposed in this paper. By employing the proposed modeling technique, models are set up in real time with the online information from input and output. The uncertainties of system dynamics are handled as internal disturbance of the system, while the perturbation from outside are taken as the external disturbance, and the combination of the two can be estimated online by a kind of active observer called extended state observer (ESO). Then a dummy variable which is equal to the sum of the known dynamics, estimated disturbance and control input can be used to establish a new simpler system, based on which control and prediction based management can be designed. Deductively, the real control variable can be solved out by the…
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Adaptation of Turbocharger to Small Displacement Single Cylinder SI Engine

Sophia University-Duan Chaoran, Yujiro Fujita, Mitsuhisa Ichiyanagi, Takashi Suzuki
  • Technical Paper
  • 2015-32-0823
Published 2015-11-17 by Society of Automotive Engineers of Japan in Japan
This paper represents the adaptation of turbo charger to single cylinder 450cc SI engine which is used for the student formula competition. The experiment and 1D engine simulation called as GT-Power were performed to confirm the effect of valve profile, compression ratio and air fuel ratio on the engine performance under the naturally aspirated condition. The maximum valve lift of the intake valves increased 27% and that of the exhaust valves increased 15% as compared with the low profile cam. The compression ratio was increased from 12.3 to 13.5 by changing the piston top land length in order to improve the thermal efficiency. It was confirmed that the torque peak was moved from 6000 rpm to 8000 rpm by changing the valve profile. Furthermore, turbo charger was adapted to the engine as changing the capacity of the turbocharger, the maximum boost pressure and the air fuel ratio. The capacity of the turbocharger was changed with expansion and contraction of the performance map of RHF25 manufactured by IHI Corporation. The genuine capacity of RHF25 worked along…
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Improving Vehicle Performance by Aerodynamic Devices in Formula SAE

Sophia University-Mitsuru Wakabayashi, Kanako Komuro, Olivier Pedoussaut, Yasufumi Oguri, Takashi Suzuki
  • Technical Paper
  • 2009-32-0103
Published 2009-11-03 by Society of Automotive Engineers of Japan in Japan
In this study, we have evaluated the performance of undertray and rear wing in formula SAE.The undertray was adopted to increase the driving force transmission. And in order to further increase the driving force and prevent the car from oversteering in high speed areas, a rear wing was mounted.Finally, by mounting these aerodynamic devices, driving force increased by 41% (undertray 14%, rear wing 27%) at the speed of 90km/h, and by calculating the value of stability factor measured by cornering power, improvement of the vehicle's oversteering tendency was confirmed.
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Analysis of Unsteady Heat Transfer on Periodical Flow in Intake Port Model

Sophia University-Takashi Suzuki, Masato Odakura, Yasufumi Oguri, Keisuke Uchida
Published 2009-04-20 by SAE International in United States
The experiments were done in order to obtain the fundamental information that would be needed to build a physical model which expresses the heat transfer phenomena in the intake port model and manifold. In the experiments, the heating conditions and the period of the cyclic change of the gas velocity were changed as experimental parameters. In addition to those parameters, the Strouhal number was applied to express oscillating flow. As a result, the heat transfer in the experiments became clear, and the equations were obtained to show the Nusselt number using the Reynolds number, the Graetz number and the Strouhal number.
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Analysis of Blow-By, Air-Fuel Mixture Gas Amount on High Speed Engine

Sophia University-Takashi Suzuki
Sophia Univ.-Kaname Suzuki, Yasufumi Oguri
  • Technical Paper
  • 2008-08-0315
Published 2008-10-22 by Society of Automotive Engineers of Japan in Japan
The purpose of the research is to analyze the amount of blow-by, air-fuel mixture in term of valve overlap by using measured intake air mass, fuel consumption, in-cylinder pressure and air-fuel ratio. In addition, to verify the propriety of analysis method, this result was compared with actual amount of blow-by gas calculated from component of exhaust gas, and the effect of blow-by gas to engine performance was considered.

Modeling and Control of Regenerative Braking System in Heavy Duty Hybrid Electrical Vehicles

Sophia University-Tielong Shen
Harbin Institute of Technology-Kai Zheng, Yu Yao
Published 2008-06-23 by SAE International in United States
We consider the modeling and control design of the regenerative braking system for heavy duty hybrid electric vehicles (HEVs) which have an isolated air-over-hydraulic (AOH) brake system and a generator. A nonlinear model is set up to characterize the behavior of the brake system. Then, the brake control is formulated as a torque tracking problem according to the driver's operations. The AOH brake system is appointed to track a constant brake torque; meanwhile, the generator is designed to track the torque error between the desired braking torque and the torque output of the AOH brake system. Finally, numerical experiments are carried out to verify the proposed model and control algorithms.
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Improvement of Middle Engine Speed Torque By Using Resonance Effect For Restricted 600cc Four-Stroke Engine

Sophia University-Makoto Ito, Hiroyuki Yano, Yasuhumi Oguri, Takashi Suzuki
  • Technical Paper
  • 2007-32-0115
Published 2007-10-30 by Society of Automotive Engineers of Japan in Japan
This research focuses on the improvement of torque at the middle engine speed of a motorcycle engine with resonance supercharging. The resonance supercharging intake system is realized with a simple modification to the intake collector geometry. A one-dimensional computational model is employed to simulate the pressure wave propagation and to optimize the configuration of it. The experiments confirmed the increase in the engine torque for the entire operation range and the maximum gain of 33% was achieved at 8500rpm. The resonance effect is further investigated through three-dimensional simulation, in which the intake airflow rate, static pressure distribution are analyzed.
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