Analysis Of The Influence On The Indoor Temperature And Humidity Fields Of The Fan Coil Unit

Fan coil unit is a kind of extensive terminal air conditioning device which has plenty of advantages such as easy to control, adjustable, low first cost and operating expenses, easy to select, small occupation, low noise and adaptive for varieties of heat and cold source. For conventional fan coil unit air conditioning system, the indoor relative humidity is difficult to be precisely guaranteed, especially in the heating period in winter, the indoor relative humidity is considerably low. In order to overcome the defects of conventional fan coil unit of humidification and improve the indoor air quality, a new type of fan coil unit wet film humidifier emerged. In this paper, comprehensive research on the specific humidifying effect of fan coil unit wet film humidifier was made, the temperature and humidity fields of the indoor air was analyzed.The control of humidity environment plays an important part in meeting the requirement of human comfort and industrial production; excessive low relative humidity will affect work efficiency and the health of the staff. After advantages and disadvantages of all kinds of humidification methods was analyzed, a conclusion was drew that wet film humidification manner is adaptive for fan coil unit. Form the point of working principle and humidification mechanism of wet film humidifier, all kinds of factors influencing humidifying efficiency and the humidification capacity control methods for wet film humidifier were analyzed, advantages and disadvantages of position switch control and modulation control of the humidification were compared.In order to investigate the effect of fan coil unit wet film humidifier on the indoor temperature and humidity fields, an office in Suzhou University was chosen as the experimental room to build the temperature and humidity testing platform. The selection and arrangement affect the results of the experiment, economic and technical analysis was made for the number of measuring points basing on the numerical simulation results. Using PVC pipe to put up the frame is to make sure that the veracity of the position of the testing point and the notability influence of the frame on the flow systems. Selection of the fan coil unit wet film was made and hot water supply system was designed, in order to avoid the fluctuation of the temperature, heat-insulated water tank was used in the system. In order to adjust the quantity of water, secondary pump adjustment method was used in the system. By comparing the advantages and disadvantages of all kinds of water heater used in projects, a type of direct frequency conversion air-source heat pump water heater was chose to be the heating source and its merits and working principle were exemplified. Measuring instrument such as inspection instrument, pyods and the humidity sensors used in the testing period were introduced. Using homemade capacitor discharge device to make pyods was introduced. The design of multimetering data acquisition system is the key to make sure the success of the experiment. In this paper, author made good use of the experiment conditions and designed psychometric testing board and not only the experiment results was made sure but also greatly reduced the cost of experiments. Production methods and testing principle was elaborated in detail.Following the numerical simulation results, appropriate experiment parameters were used to test the indoor temperature and humidity field's distribution before and after the humidification. A conclusion was draw that the fan coil unit wet film humidifier can overcome the problem that indoor relative humidity is considerably low in winter. By comparing and anglicizing the results of the experiment results, selection principle of the fan coil unit wet film humidifier was proposed and the conclusion that the influence regularity of the fan coil unit wet film humidifier on the indoor temperature and humidity was drew.