Influencing assessment of different heating modes on thermal comfort in electric vehicle cabin

Electric vehicle(EV)is more environmental-friendly than gasoline vehicle because the main power is not petrol.For the heating system,the waste heat generated by engines is recycled to heat the cabin of gasoline ones,while the EV need extra electric energy consumption for heating the cabin which decreases the driving range.Personal comfort system(PCS)has been reported that it is an alternative technique to improve occupant thermal comfort and indirectly save building heating energy.This study aims to investigate the occupants’thermal sensation under four heating modes in the EV cabin in winter,including no heating,only PCS,only air conditioning,and both air conditioning and PCS.The field survey is conducted in a parked EV with 12 subjects.Three thermal comfort indexes(PMV,SET^(*),and operative temperature Top)are used and assessed for their applicability in the thermal environment of the EV.Results show that the thermal environment in the cabin is non-uniform and dynamic with the air conditioning mode,while the PCS mode just slightly affects the temperature differences inside.Meanwhile,the subjects’thermal sensations cannot maintain neutral or warmer under the PCS mode only.The results of PMV are lower than the subjects’actual thermal sensation votes(TSV),while the results of SET^(*)and Top show significant linear relationships with the TSV for the correlation coefficients above 0.80.Compare to the air conditioning mode,the neutral SET^(*)and neutral Top are decreased by 2.7℃ and 1.6℃ under the mode with PCS and air conditioning,respectively.The findings indicate that PCS not only has a positive effect on improving the cabin environment and occupant’s thermal sensation but also has the potential to lower the setting temperature of air conditioner of EVs in winter.

Low Temperature Growth of Vertically Aligned Carbon Nanotubes via Floating Catalyst Chemical Vapor Deposition Method

Synthesis of carbon nanotubes （CNTs） below 600℃ using supporting catalyst chemical vapor deposition method was reported by many research groups. However, the floating catalyst chemical vapor deposition received less attention due to imperfect nanotubes produced. In this work, the effects of varying the preheating temperature on the synthesis of CNT were investigated. The reaction temperature was set at 570℃. The preheating set temperature was varied from 150 to 400℃ at 50℃ interval. Three O-ring shape heating mantels were used as heating source for the preheater. In situ monitoring device was used to observe the temperature profile in the reactor. Benzene and ferrocene were used as the carbon source and catalyst precursor, respectively. Vertically aligned CNTs were synthesized when the preheating temperature was set at 400℃. When the preheating temperature was increased up to 400℃, both the length and the alignment of CNTs produced were improved.