A Study On Optimizing Automotive Air Conditioning For Cabin Comfort

Jun Suzuki･Masaharu Marumoto･Akane Masui･Koki Kawakami･Akira Togi (Mazda)

In order to improve the comfort of automotive air conditioning and reduce energy consumption, we developed a CFD surrogate model that quickly calculates convective airflow in the cabin. Using parameter studies and optimization, we clarified how air conditioning blowing conditions (air volume, distribution, etc.) affect the temperature field and velocity field distribution near different parts of the human body.

Experimental Validation of Reynolds-Averaged Turbulence Models for Air-Conditioning Supply Jets in a Vehicle Cabin

Kazuki Ito (Hiroshima University)･Masahiro Morishita･Kouhei Mutou (Highly Marelli Japan)･Takuji Nakashima (Hiroshima University)･Itsuhei Kohri (Tokyo City University)･Yoshiichi Ozeki (AGC)･Minoru Inoue (Mazda)･Kazuhiko Matsunaga (Kanagawa Prefectural Junior College for Industrial Technology)･Hidemi Mutsuda (Hiroshima University)

Accurate evaluation of occupant equivalent temperature in vehicle cabin air-conditioning requires heat-balance prediction that accounts for convective heat-transfer coefficients. Therefore, improving HVAC airflow prediction remains important. This study investigates a supply jet and validates the reproducibility of turbulent energy transport mechanisms in the Realizable k–ε model through comparison with measurements obtained using a high-response multi-hole probe. Based on the results, challenges for further improving prediction accuracy are clarified.

The Effect of Reducing the GWP of Refrigerants on the Heat Transfer Performance of Oscillating heat pipe

Rikuto Dogan (Tohoku University)･Yasutaka Negishi･Asuka Bunno･Yuji Mihara (Daikin Industries)･Ayuki Kano･Ayumu Shimizu･Hiroki Nagai (Tohoku University)

Oscillating heat pipe (OHP) have attracted attention as thin, lightweight, and high-heat-spreading devices. This study aims to apply OHPs to mobility applications and experimentally investigates the heat transport performance of an OHP filled with R474B, a next-generation low-GWP refrigerant. Through the measurements of internal pressure and tube wall temperature, as well as comparisons with other refrigerants, the effects of differences in refrigerant properties on the heat transport performance of the OHP were evaluated.

Fundamental Properties of POE Refrigeration Oils for Low GWP Refrigerants

Yusei Minagawa･Tomohiro Takaki･Ken Sawada･Tsukasa Sakuraba･Yuya Mizutani (ENEOS)

In recent years, refrigerants with low global warming potential (GWP) and low environmental impact have attracted attention in the field of refrigeration and air-conditioning systems. This report presents evaluation results for various properties of refrigeration oils used to lubricate refrigeration compressors under the conditions of low GWP refrigerants such as R290 (propane).