Air conditioner is the key air supply device to improve the indoor air heat transfer cycle and thermal environment. In this paper, according to the similarity theory, six kinds of the multi-impeller air conditioners (MIAC) with different numbers of axial-flow impeller are first proposed based on air conditioners with cross-flow fan (CFAC). The effects of different multi-impeller air supply modes on the indoor airflow field and temperature field are investigated by using the numerical simulation method. The validity of the computational model and method is verified by comparing the experimental measurements and numerical results. Compared with other air supply modes, the air supply distance is relatively far and the indoor environment is also improved obviously when the six-impeller air conditioner (SIAC) is used. The independent multiple impellers and outlets of SIAC make the mutual interference between the outlet airflow less, which effectively reduces the friction between the airflow and the degree of loss along the way and makes the cold and heat exchange of the whole indoor space more sufficient. The indoor thermal environment is also analyzed by using the PMV-PPD method and prototype experiment. Under the working condition of no wind, the indoor thermal comfort of human body with SIAC is better than that of CFAC. Especially in the horizontal plane of 0.6 m above the human foot, the indoor thermal environment improvement effect is the most obvious. Simultaneously, the temperature difference along the indoor height direction with the SIAC is only 1.7°C, which is 70% lower than that of the CFAC. The blowing angle between the left and right side of the SIAC is 106°, which is 31% higher than that of the CFAC. Therefore, the overall thermal comfort of the six-impeller mode is better, and the control effect of indoor environment is satisfactory.
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