路面融雪化冰可靠性分析

Reliability analysis of pavement snow melting based on multi-factor

为研究多个随机因素对地源热泵路面融雪化冰可靠性的影响,在分析融雪化冰原理的基础上,以可靠性理论为工具,建立了考虑多个参数随机性的可靠性方程.介绍了中心点法和验算点法,利用中心点法直接推导出可靠指标和失效概率计算公式,用验算点法结合迭代法求出可靠指标及验算点设计值.结合工程实例考虑不同环境条件及可靠度条件下融雪化冰的耗热量,结果表明降雪量的变异性、室外温度的变异性对耗热量有较大影响.与只考虑降雪量一个随机因素的变化相比,考虑降雪量、室外温度多因素影响的耗热量虽说会增加,但更能保证系统的安全、稳定,同时降雪量的变化对耗热量的影响比室外温度变化对耗热量的影响显著.中心点法和验算点法对比表明,两者的结论是一致的,采用验算点法的计算量比中心点法大,但验算点法计算精度较高.

To investigate the effects of multiple random factors on ground-source heat pump reliability, the reliability equation were established based on the analysis of the principle of deicing and snow melting and the random character of snow melting system which concerns the stochastic characters of multiple factors. The centre point method and checking point method were introduced. Reliability index and failure probability calculation formulas can directly deduced by using the centre point method. Reliability index and design value of checking point can be determined by the checking point method combined with the iterative method. Combined with engineering example, heat load of deicing and snow melting were calculated given different environment conditions and reliability conditions. The heat load will increased based on snowfall and outdoor temperature randomness compared with only concerning the snowfall randomness, but that can guarantee the stability and safety of the system. At the same time, compared to outdoor temperature, snowfall has the most significant impact on heat load. Compared to the center point method and the checking point method, their conclusions are consistent. The calculation amount of the checking point method is bigger than central point method＇s, but the calculation accuracy of checking point method is higher.