Your Selections

Ozeki, Yoshiichi
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Events

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Evaluation of Equivalent Temperature in a Vehicle Cabin with a Numerical Thermal Manikin (Part 2): Evaluation of Thermal Environment and Equivalent Temperature in a Vehicle Cabin

AGC Inc.-Yoshiichi Ozeki, Seiko Suzuki
Nissan Motor Co., Ltd.-Hajime Oi, Yasushi Ichikawa, Akira Matsumoto
Published 2019-04-02 by SAE International in United States
In the previous paper (Part 1), measurements of equivalent temperature (teq) using a clothed thermal manikin and modeling of the clothed thermal manikin for teq simulation were discussed. In this paper (Part 2), the outline of the proposed mesh-free simulation method is described and comparisons between teq in the calculations and measurements under summer cooling with solar radiation and winter heating without solar radiation conditions in a vehicle cabin are discussed. The key factors for evaluating teq on each body segment of the clothed thermal manikin under cooling and heating conditions are also discussed. In the mesh-free simulation, even if there is a hole or an unnecessary shape on the CAD model, only a group of points whose density is controlled in the simulation area is generated without modifying the CAD model. Therefore, the fluid mesh required by conventional CFD code is not required, and the analysis load is significantly reduced. The most advantageous point is that this mesh-free simulation method satisfies the conservation laws of mass, momentum, and energy. The cabin thermal environment and…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Simple Prediction for Fuel Consumption and Cruising Distance of Internal Combustion Engine Vehicles with RFD Method

AGC Inc.-Miyoko Oiwake, Yoshiichi Ozeki
Tokyo City University-Hideaki Nagano, Memori Ikeda, Itsuhei Kohri
Published 2019-04-02 by SAE International in United States
In order to develop various parts and components of vehicles, understanding the effects of their structures and thermal performance on the fuel consumption and cruising distance is important. However, because of the limited information available to parts suppliers, it is not always easy to predict and study vehicle fuel efficiency and cruising range performance under arbitrary driving conditions. In this study, the authors have developed an RFD (Regression Fuel-consumption Diagram) method to predict the cruising performance of internal-combustion engine vehicles (ICEV) based only on the published information given to suppliers by using standard reference vehicles, which had been regressed and identified for control characteristics and fuel consumption diagrams. As an example of the application of the RFD method to realistic situation, the effects of the driving mode and air-conditioning on the fuel consumption of ICEV are studied. Accordingly, it was found that the influence of the air-conditioning load on the fuel consumption differs depending on the driving modes. In addition, for the validation of the standard reference models introduced in the RFD method, the influence…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Evaluation of Equivalent Temperature in a Vehicle Cabin with a Numerical Thermal Manikin (Part 1): Measurement of Equivalent Temperature in a Vehicle Cabin and Development of a Numerical Thermal Manikin

AGC Inc.-Yoshiichi Ozeki, Seiko Suzuki
Nissan Motor Co., Ltd.-Hajime Oi, Yasushi Ichikawa, Akira Matsumoto, Fusaaki Takeo
Published 2019-04-02 by SAE International in United States
The present paper is Part 1 of two consecutive studies. Part 1 describes three subjects: definition of the equivalent temperature (teq), measurements of teq using a clothed thermal manikin in a vehicle cabin, and modeling of the clothed thermal manikin for teq simulation. After defining teq, a method for measuring teq with a clothed thermal manikin was examined. Two techniques were proposed in this study: the definition of “the total heat transfer coefficient between the skin surface and the environment in a standard environment (hcal)” based on the thermal insulation of clothing (Icl), and a method of measuring Icl in consideration of the area factor (fcl), which indicates the ratio of the clothing surface to the manikin surface area. Then, teq was measured in an actual vehicle cabin by the proposed method under two conditions: a summer cooling condition with solar radiation and a winter heating condition without solar radiation. The results showed that teq, including the effects of the air temperature, air velocity and thermal radiation, was measured properly. Subsequently, a numerical thermal manikin…
This content contains downloadable datasets
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Effects of the Glass and Body Heat Transfer Characteristics of an Electric Vehicle on its Energy Consumption and Cruising Distance

SAE International Journal of Passenger Cars - Mechanical Systems

Asahi Glass Co., Ltd.-Yoshiichi Ozeki
Tokyo City University-Hideaki Nagano, Itsuhei Kohri
  • Journal Article
  • 2016-01-0260
Published 2016-04-05 by SAE International in United States
In order to develop various parts and components of electric vehicles, understanding the effects of their structures and thermal performance on the energy consumption and cruising distance is important. However, such essential and detailed information is generally not always available to suppliers of vehicle parts and components. This paper presents the development of a simple model of the energy consumption by an electric vehicle in order to roughly calculate the cruising performance based only on the published information to give to suppliers, who otherwise cannot obtain the necessary information. The method can calculate the cruising distance within an error of 4% compared to the published information. The effects of the glass and body heat transfer characteristics on the cruising performance in winter were considered as an example application of the proposed model. An anti-fog control method was modeled, where the relative humidity around the front windshield was assumed to be detected and the recirculation ratio of the ventilation was controlled in order to maintain defogging. The effect of the anti-fog control combined with the thermal…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Evaluation on the Solar Reduction Glass in an Electric Vehicle by Experimental Measurements in a Climate Chamber

Asahi Glass Co., Ltd.-Yoshiichi Ozeki, Yuko Harita, Akira Hirano, Jiro Nishihama
Published 2014-04-01 by SAE International in United States
Solar energy through glass windows has an influence on the thermal environment in the cabin and thermal comfort of occupants. A medium-size electric vehicle (EV) is conducted for evaluating the performance of solar reduction glass under summer conditions in the climate chamber by experimental measurements. For this purpose, two kinds of glass are attached to the medium-size EV with different performance of solar reduction rate (IR-cut type and normal type). In this paper, two types of experimental measurements, steady state and unsteady state conditions, are conducted. Surface temperature, air temperature and electric consumption of air conditioner are measured under some conditions of air-conditioner. EHT (Equivalent Homogeneous Temperature) by thermal manikin, thermal sensation and thermal comfort by male and female subjects are also measured. Significant difference in the measured surface temperature of the instrument panel where solar radiation reaches through the glass window is found between IR-Cut glass and normal glass. In addition, one or two rank difference in the thermal comfort at the part where solar radiation reaches is found, and “hot” thermal sensation and…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Analysis of Heat Transfer Characteristics in Modeled Compact Car

Asahi Glass Co., Ltd.-Yoshiichi Ozeki
DENSO Co.-Takuya Kataoka
  • Technical Paper
  • 2012-08-0328
Published 2012-05-23 by Society of Automotive Engineers of Japan in Japan
Vehicle interior environment is one of the important issues for the passenger's thermal sensation. Scaled model of vehicle cabin was created and the experiment was done to obtain the detailed information of heat transfer characteristics inside the cabin under the non-isothermal condition. The temperatures of inner and outer surface and air were measured to evaluate the thermal environment of the cabin. Besides, CFD simulation was also conducted to evaluate CRI index, which can make clear the characteristics of the thermal environment. The results lead to enhancement of the data of the standard model of the cabin.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Ventilation Characteristics of Modeled Compact Car Part 5 - Scaled Model Experiment for Heat Transfer Characteristics

Asahi Glass Co Ltd-Yoshiichi Ozeki
DENSO Corp-Takuya Kataoka
Published 2012-04-16 by SAE International in United States
Accuracy of numerical simulation has to be evaluated through the actual phenomenon such as experiment or measurement and then it can be employed to design the air-conditioning system of car cabin at the development phase. Scaled model of vehicle cabin was created by the Society of Automotive Engineers of Japan (JSAE) and the experiment was performed to obtain the detailed information of heat transfer characteristics inside the cabin under the non-isothermal condition. The sheet heaters were put to the inner surface of the acrylic cabin and they supplied certain amount of heat. The temperatures of inner and outer surface and air were measured to evaluate the thermal environment of the cabin. The results lead to enhancement of the data of the standard model of the cabin.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Ventilation Characteristics of Modeled Compact Car Part 6 - Numerical Analysis of Heat Transfer Characteristics by CRI

Asahi Glass Co Ltd-Yoshiichi Ozeki
IIS, the University of Tokyo-Shinsuke Kato
Published 2012-04-16 by SAE International in United States
In the present study, numerical simulation coupling convection and radiation in vehicle was done to analyze the formation of the temperature field under the non-uniform thermal condition. The scaled cabin model of simplified compact car was used and the thermal condition was determined. The fore floor, the top side of the inst. panel, the front window and the ceiling were heat source. The lateral side walls were cooled by the outdoor air and the other surfaces were adiabatic. It is same with the experimental condition presented in Part 5. In order to analyze the individual influence of each heat source, Contribution Ratio of Indoor climate (CRI) index was used. CRI is defined as the ratio of the temperature rise at a point from one individual heat source to the temperature rise under the perfect mixing conditions for the same heat source. The simulation results showed the large gradient of the air temperature in the vicinity of the ceiling above the front seat and the temperature in other area was almost 18°C. There was circulating flow…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Evaluation on Thermal Environment in a Truck Cabin (Part 2)~Analysis of Indoor Measurements in Winter Condition

Yoshiichi Ozeki, Kazuhiko Matsunaga
  • Technical Paper
  • 2011-08-0665
Published 2011-10-12 by Society of Automotive Engineers of Japan in Japan
Heat transfer characteristics of the thermal environment for the practical method predicting the heat load are analyzed by a statistic method on the basis of the measurements in a truck cabin under the winter condition. Measured results are applied to the heat balance equations of air in the whole cabin or on the surfaces inside and outside the cabin for this purpose. In the second paper, how the methods of setting convective heat transfer rate on body surface and air temperature inside the cabin affect the heat balance equation of air in the whole cabin are also discussed under the conditions of foot and bi-level mode. It is found the vertical air temperature distribution could be taken into account for the accurate prediction of heat balance, and the distribution of appropriate convective heat transfer rates is also important for the accurate prediction of heat load in the winter condition as well as the results of the summer condition.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Thermal Fluid Analysis By a Mesh Free Simulation - Part 2 Analysis of the Indoor Climate in a Vehicle Cabin Based on the 3D-CAD Model

Asahi Glass Co. Ltd.-Yoshiichi Ozeki, Tsunehiro Saito
Mazda Motor Corp.-Minoru Inoue, Hiroaki Masuoka, Takaki Nakamura
Published 2011-10-06 by The Automotive Research Association of India in India
The thermal fluid field in a vehicle cabin model is analyzed by the mesh free method as well as mentioned in the Part 1. This paper focuses on the steady state indoor climate in the vehicle cabin including the effect of the buoyancy, the heat generation of the driver and heat conduction through the vehicle body surface under the maximum air-cooling condition soaked in a climate chamber in the summer condition for the demonstration of the mesh free method without not only the deformation of the 3D-CAD model but mesh generation. The solar radiation distribution and heat generation through the exhaust pipe from the engine room are simply included in the analysis. Simulated results are compared with experiments in the conditions of both moving and idling states. As a result, no significant difference in air temperature between simulation and experiments can be obtained in both conditions. It is found the conducted method is recognized as a powerful tool which can analyze the indoor climate in the vehicle cabin based on the 3D-CAD model directly.
Annotation ability available