变负荷工况区域供冷管网冷损失分析

介绍了区域供冷管网的冷损失计算方法,并对典型项目在不同敷设方式、不同负荷率下的管网冷损失进行了计算。结果表明:直埋敷设方式的管网冷损失最小;设计工况下,二次管网冷损失在总输送冷量中占比较小,可控制在1%以下,其中二级泵造成的冷损失占比可达78%以上,是管网冷损失的主要因素。不同负荷工况下,二级泵与管道冷损失比例变化明显:负荷率为80%时,二级泵造成的冷损失占比为75%左右;负荷率为30%时,二者所占比例接近,各占总冷损失的50%;负荷率为10%时,管道冷损失占比达到70%以上,成为系统冷损失的主要部分。

Cooling loss of district cooling pipe network under variable load conditions

Presents the calculation method of cooling loss for district cooling pipe network and calculates the cooling loss of pipe network under different laying ways and load rates for a typical project.The result shows that directly buried pipe network can keep a minimum cooling loss.The cooling loss of the secondary pipe network accounts for a small part of its total transport cooling capacity,which can be controlled less than 1%,and the cooling loss of the secondary pump is the key factor and can account for more than 78%under design condition.Cooling loss rates of secondary pump and pipe change significantly under different load rates.The cooling loss of secondary pump accounts for 75%under 80%load rate,and the cooling loss of pipe and secondary pump each accounts for 50%under 30%load rate.However,the cooling loss of pipe accounts for 70%under 10%load rate,which becomes the main part of system cooling loss.