Air Quality and Comfort Characterisation within an Electric Vehicle Cabin in Heating and Cooling Operations

This work is aimed at the experimental characterisation of air quality and thermal profile within an electric vehicle cabin, measuring at the same time the HVAC system energy consumption. Pollutant concentrations in the vehicle cabin are measured by means of a low-cost system of sensors. The effects of the HVAC system configuration, such as fresh-air and recirculation mode, on cabin air quality, are discussed. It is shown that the PM concentrations observed in recirculation mode are lower than those in fresh-air mode, while VOC concentrations are generally higher in recirculation than in fresh-air mode. The energy consumption is compared in different configurations of the HVAC system. The novelty of this work is the combined measurement of important comfort parameters such as air temperature distribution and air quality within the vehicle, together with the real time energy consumption of the HVAC system. A wider concept of comfort is enabled, based on the use of low-cost sensors in the automotive field.

Investigation of the Effect of Solar Ventilation on the Cabin Temperature of Vehicles Parked under the Sun

During hot days, the temperature inside vehicles parked under the sun is very high; according to previous studies, the vehicle cabin temperature can be more than 20 °C higher than the ambient temperature. Due to the greenhouse effect, the heating that occurs inside a vehicle while it is parked under the sun has an impact on energy crises and environmental pollution. In addition, the increase in the temperature inside the cabin will have an effect on the dashboard and plastic accessories and the leather on the seats will age rapidly. The ventilation of solar energy from the cabin of a vehicle parked under the blazing sun has received a great deal of attention. The present study was conducted to utilize a renewable energy system to operate the ventilation system through a novel portable ventilation system powered by solar energy. Experimental results were obtained for a vehicle with and without the solar ventilation system. The results indicate that the maximum daily average difference in temperature during the experimental tests between the cabin of the car and the atmospheric temperature with and without the solar ventilation system was 7.2 °C and 20.6 °C, respectively. With and without the usage of the system, the minimum average difference in temperature between the automobile’s cabin and the atmospheric temperature was 6.2 °C and 17.6 °C, respectively. The results indicate that the proposed system is effective and that the thermal comfort inside the vehicle’s cabin improved when the vehicle was parked under the hot sun. Therefore, this system helps to protect human bodies, conserve energy, protect the environment, protect the vehicle’s cabin, and provide a comfortable environment.

HVAC CFD Analysis of Air Flow and Temperature Distribution Inside Passenger Compartment

The thermal environment and air quality in a passenger car can affect driver's and passengers' health, performance and comfort. Due to spatial and temporal variation of state variables and boundary conditions in the vehicle cabin, the heating, ventilating and air-conditioning (HVAC) does not have to be designed to provide a uniform environment. This are due to individual differences regarding to physiological and psychological response, clothing insulation, activity, air temperature and air movement preference. Experimental study in vehicle HVAC system can be very costly to be conducted. In order to analyze the air flow and temperature distribution in passengers compartment, a numerical simulation was used in this study to analyze the air flow and temperature distribution of HVAC unit inside Proton Exora passengers compartment, with the air blower speed and air temperature used as parameter, to evaluate the airflow behavior and temperature distribution in the compartment. The simulation data obtained is then compared to the experimental data, showing good agreement between these two methods.

Air Contaminants in an Underwater Vehicle Cabin During Navigation

The purpose of this study is to study the air contaminants in the cabins of underwater vehicle. The basic data help for the better research of the underwater vehicle cabin environment standard and the control strategy. Pretreatment and analysis method of volatile organic compounds was preconcentration combined with gas chromatography under the condition of liquid nitrogen and detected by chromatography-mass spectrometry. The pollution of particles, carbon monoxide and carbon dioxide during the underwater vehicle voyage were monitored by online monitoring instrument. Altogether 34 kinds of pollution components were detected, most of which were low in concentration. Some are low olfactory threshold or high toxic components, such as dimethyldisulfide, benzene, carbon disulfide, trichloromethane, and several reached to ppm level. The contamination of the particles was mainly fine particles and part cabins exceeded the national standard of indoor air quality. The highest concentration of carbon dioxide in accommodation space exceeded the permissible concentration of atmosphere composition aboard diesel underwater vehicle compartments. The increase submerged time made the environment in the cabins deteriorate. The concentration of trace contaminants may close to or beyond the relevant standards with the prolonged time. The volatile organic compounds, particles, carbon monoxide and carbon dioxide aggravated the air circumstance in the cabins. It should be determined the permissible concentration of air contaminants in underwater vehicle as soon as possible.

Efficiency of the Vehicle Cabin Air Filters for Removing Black Carbon Particles and BTEX from the Air Intake

A laboratory study was conducted to evaluate 11 vehicular cabin filters (including electrostatic filters) in removing fine particles. Two filters with charcoal were also evaluated to understand their usefulness in removing five common volatile organic compounds, including benzene, toluene, ethylbenzene, and xylene isomers (BTEX). Filters were found to show considerably different particle filtration efficiencies (FE). Electrostatic filters were found to provide 20–60% better FE across all particle diameters (6–520 nm). For 6 nm particles, FE from 78 to 94% were observed (from the worst to the best filters), while at 520 nm, FE varied from 35 to 60%. The best group of filters provided 44–46% FE for capturing the most penetrating particles (100–300 nm), while the worst group of filters provided only 10–11% FE. The filtration behavior of nominal filters was typically stable (with respect to particle number, black carbon, and particulate matter mass) over the course of 1–2 years of usage. The benefits of the electrostatic filters were significant, but such advantages were observed to gradually dissipate over the course of about 1 year; by then, the electrostatic filter becomes no different compared to a nominal filter in terms of filtration behavior. Charcoal filters showed variabilities in removing BTEX, and removal efficiencies varied from 11 to 41%.