Due to the limitation of civil construction conditions, although the system can not achieve the new wind in the transition season, it can reduce the number of revolutions and sound power level of the fan, reduce the difficulty of the muffling process, and ensure that the fresh air volume reaches the design value. Noise requirements Because the concert hall has high requirements for noise control, the noise of the air conditioning system is accounted for, and 6 noise reductions are provided on the return air duct of the connected equipment to ensure that the airflow noise in the air duct and the mechanical vibration noise of the equipment are low. The noise allowed value in the concert hall. In particular, the VDL swirling tuyere increases the airflow noise generated by the tuyere as the air supply volume increases. For example, when the air supply volume is 1974m3/h, the airflow A sound level noise is 35dB, which seems to exceed the concert hall. The noise allows the value, but in fact, after converting the sound power level into the noise level of the noise in the room, the noise can be reduced by 1520dB, which can meet the noise requirements of the concert hall. Partial seat back air supply, air supply on the main body This air conditioning air supply method is proposed by the Japanese side and insists on implementation. It is a two-way method to meet the owner's requirements for the lower air supply mode without extensive modification of existing civil construction conditions. Brief introduction to the scheme This is based on the height of the concert hall, and the area farthest from the ceiling (approximately 650 seats) is used as the back air supply area. The air treated by the air conditioner is sent to each seat by the air duct, and then sent back by the seat back. The return air returns from the lower end of the seat armrest to the air tank, and then returns to the underground machine room by the return air duct. The stage and other auditorium areas use a swirling tuyere to blow the wind from the ceiling, and return to the wind from the mushroom-type return air outlet under the seat. As a whole, the airflow organization accounts for the majority of the air volume of the swirling tuyere, so the form of the upper and lower returns is the mainstream. For the partial seat back air supply area, the air supply opening is in the breathing zone of the person, and the air returning opening is on the ground, and the air flow forms a small loop at each seat to ensure a uniform temperature field in the upper part of the seat. The wind speed of the seat back air outlet is 1.7m/s, the effective area of ​​the air outlet is 0.006m2, and the airflow direction is at an angle of 16b with the vertical direction. It does not directly blow the person's face, the comfort is guaranteed, and the air quality is good. The air circulation range is small in this area and the pre-cooling time is short. Forged Shaft,Hollow Shaft,Shaft Forging Part,Stainless Steel Shaft Suzhou SNK Machinery Equipment Co.,LTD , https://www.snkforging.com