## 1 Introduction
Therefore, it is not desirable to have a high air age [20]. A limited number of studies in the literature show that the position and the location of the air cleaner affects the air flow patterns and changes air cleaning efficiencies [21]. It has been shown that air cleaning device (ACD) placement is an important parameter with respect to pollutant removal performance, especially at low flow rates [22]. In addition, the direction of the air flow also affects the efficiency of the device [23]. The most important parameter affecting ACD performance is volumetric flow rate [20]. The pollutant removal is not only dependent on the ACD, but also on the room in which the device is located and the furniture used in this room [23]. One of the methods used to improve the performance of ACDs is to change the control strategy. [PERSON] et al. [24] showed that the performance of such devices could be improved with the zone control approach. ACDs have various performance characteristics on different types of pollutants. [PERSON] et al. [14] used experimental and computational fluid dynamics (CFD) methods to investigate the risk of infection resulting from particle exposure in a model lecture hall and determine the best location for an air purifier. According to their findings, changes in position and orientation would result in a 13% deviation in the particle concentration at head height. They came to the additional conclusion that air purification is a useful strategy for lowering aerosol particle concentrations. [PERSON] et al. [25] stated that the CADR value decreases with increasing particle size. The filter technologies used in these devices also significantly affect device performance [26]. The cleaning performance and electricity consumption of ACDs are often compared with those of air conditioners (AC). In these comparisons, it has been concluded that ACDs are better than ACs in terms of both energy consumption and cleaning performance [27; 28]. Although ACDs reduce the pollutant concentration in the environment, some disadvantages are also included in the literature. With regard to the disadvantages, filter lifetime has been reported as one, as, in air cleaners, it is between 1 and 3 months, depending on the pollutant concentrations [29]. In addition, secondary products emitted from these devices are important in terms of indoor air quality [30]. [PERSON] et al. [31] reported that the position of the aerosol source and the airflow pattern produced by the air cleaner and heating device in the room have a significant impact on the efficiency of the air purification process. According to the aforementioned research in the current literature, there is limited work considering the performance of portable air cleaner devices by using CFD tools. However, there is no reported assessment study employing both the CADR and the mean age of air methods. The aim of this study is to investigate the performance of the air cleaner under different operating conditions by using both the CADR and the mean age of air methods. In the performance evaluation of an ACD, the obtained information from both methods are compared and discussed in detail. Air velocity and age of air distributions in a room were calculated using three-dimensional CFD. In the numerical tical study, two different locations of the air cleaner device and three different blowing speeds were considered. In addition to that, the particle cleaning performance of the device was also investigated by randomly injecting different size particles into the indoor air, the results of which were compared and interpreted.