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• The cabin heat dissipation was analyzed under two ventilation modes (air supply/air exhaust). • The Experimental devices and CFD method were introduced and the results comparison were made. • The flow fields of the two conditions were analyzed and compared. • A better heat dissipation environment of reefer container was obtained in the air supply condition. In global refrigerated transportation, marine reefers play an extremely important role. Considering the high freight cost and harsh surroundings of the decks during the voyage, reefer containers are always loaded into cabins for safe and economical purpose. However, under severe environment conditions in cabin , the refrigeration efficiency of reefer units was greatly affected, because of the weak ventilation and low heat exchange capacity. In order to find a more scientific and reasonable way to ventilate the cabin of reefer containers, two different ventilation modes, that is, air supply and air exhaust, were experimented and simulated. The temperature distribution was analyzed in a typical reefer cabin with 14.4 m (in length) × 23.2 m (in width) × 16.85 m (in height). Compared with two contrary ventilation modes, the temperature distribution in the cabin at steady state was simulated and analyzed. The results show that, the temperature of the cabin under the air exhaust condition was about 4K lower than that under the air supply condition. But with higher heat dissipation efficiency, the air exhaust condition sacrifices the uniformity of the temperature in the cabin. A relatively uniform temperature distribution and airflow field were obtained under air supply condition. Therefore, considering the heat dissipation effect of the container and the uniformity of airflow distribution, the air supply method was recommended. The two ventilation modes were compared in detail in this paper, and the results provide a reference for ventilation design of reefer container vessels. [ABSTRACT FROM AUTHOR]

Studies on the thermal environment of the electronic radar shelter have been mainly focused on the simulation of the unmanned thermal environment, and there have been few studies on experiments in the thermal environment. Additionally, a comparative study of the experimental results from manned and unmanned shelters has been missing. In this paper, we experimented in thermal environments of manned/unmanned shelter under different air supply conditions. The experiment was divided into cooled, ventilated, and heated trials analyzing three aspects: (1) The average temperature distributions of walls, air inlet points, air outlet points, and surfaces were measured over time under different conditions in an unmanned shelter. The temperature distribution curve was fitted into the function. (2) Based on different working conditions, the temperature distribution experiments were carried out in three different areas for subjects wearing short or long clothing respectively. (3) The wind speed was measured at each measuring point in the air supply pipeline under different working conditions. The wind speed distribution was detected on the setting surfaces. The experimental results show that: (1) The air does not gradually tend to steady state with the time, and under different conditions, the air temperature obviously differs. (2) The clothing selection, air supply conditions, and locations of measuring points have significant influences on human body temperature distribution and left–right difference. (3) The mixing of the thermal plume caused by the vertical temperature difference of the human body and the jet generated by the mechanical air supply will reduce the wind speed of the airflow in the cabin, the adsorption of the jet to the bulkhead, and the stability of the airflow. The experimental data can provide the initial and boundary conditions for the simulation of the shelter. The results can provide a reference for the study of fluid control methods, the setting of thermal boundary conditions, and the simulation of the influence of thermal plumes on the airflow distribution. The experimental study in this paper has filled in the blanks regarding experimental study in electronic radar shelters. It has important research value and practical significance. [ABSTRACT FROM AUTHOR]