The Economic Operation Research On Variable-speed Fan In Open Pipe Network Systerm

At present, architectural energy saving is the important part in the energy saving field. In China, architectural energy consumption, in which fan consumption is the big one, is about 25% of the total energy consumption. Variable flow volume technology is the efficient measure to save energy. In recent years, we have made some progress on the research of variable flow volume, but we have different opinon on the efficiency of the energy saving, so we need further research on it.Based on the research result of abroad, fan test and theory analysis, we can make two conclusions, as follows:1. When the valve lift is commanded, fan speed regulates with the load, under this condition, the efficiency of fan is constant, the relative head is square to the relative flow, and the relative power is cubic to the relative flow.2. In actual operation, fan, duct, valve, coil is an integration of system. The actual flow rate of fan is affected by the charactesistic of pipe resistance. In practice, the actual fan power is larger than the design one, and the relative power is not equal to the cubic of the relative flow.