实验五 空气_蒸汽对流给热系数.doc

实验五 空气蒸汽对流给热系数的测定1、 实验数据记录及处理 蒸汽压强P=0.03MPa 表1 原始数据记录冷流体进口温度t1冷流体出口温度t2蒸汽进口温度T1蒸汽出口温度T2空气流量qv（m3/h）53.982.5102.5103.121.553.782.8102.5103.217.553.583102.5103.11551.883.1102.31031049.982.9102.4103.17.547.682.5102.4103.25 表2 冷流体特性参数空气流速u（m/s）对数平均温度差t冷流体平均温度空气密度(Kg/m3)空气质量流量qm（Kg/h)空气黏度(Pa/s)10-5空气的导热系数（WmK)29.732.468.21.078123.182.04862.98E-0224.232.368.251.078818.882.04880.029820.732.268.251.079516.192.04880.029813.832.667.451.085310.852.04510.029710.433.666.41.0928.192.04010.02966.934.765.051.10015.52.03370.0295 表3 特征数关联式的确定努赛尔数Nu雷诺数RePr总传热系数K（WmK）l(Nu/Pr0.4)lRe61.26250080.6940.695114.11.854.450.9020388.10.69494.8 1.774.3144.4017450.70.69482.7 1.71 4.2431.5711717.50.69558.61.564.0723.278906.90.69544.91.433.9516.715980.60.69630.81.293.782、 将Nu=61.26,Re=25008;Nu=50.90,Re=20388.1，Pr=0.695代入公式Nu/Pr0.4=ARem 即61.26/0.6950.4=A25008m 50.90/0.6950.4=A20388.1m解得A=0.00727 , m=0.907准数关联式 Nu=0.00623 Re0.907 3、 以l(Nu/Pr0.4)为纵坐标，l Re为横坐标，将实验数据结果标绘在双对数图上 图1由图得lg(Nu/0.6950.4)=2.164+0.913lgRe 则 m=0.913, lg A=2.614，即A=0.00243 故 准数关联式 Nu=0.0021 Re0.913 实验七 板式塔精馏实验实验数据的记录及处理 回流比R=3 表1 全回流 塔釜温度预热温度产品温度板10温度板9温度板8温度板7温度板6温度板5温度板3温度板2温度板1温度78.733.923.875.775.576.376.476.776.977.275.978.978.843.223.975.875.676.276.476.576.776.875.678.878.943.524.275.875.576.276.476.576.776.875.678.878.943.624.475.875.676.276.476.576.776.975.778.8 部分回流 79.244.224.775.975.776.376.476.676.776.975.87979.540.636.276.175.976.877.577.877.878.176.479.480.340.338.976.17676.877.477.777.778.176.679.882.240.653.476.17676.877.477.877.878.276.980.5 表2密度（g/mL)质量百分数%摩尔分数全回流塔釜浓度0.9430.10.144塔底浓度0.8295.20.886部分回流塔釜浓度0.96517.50.077进料浓度37.70.191塔底浓度0.82587.70.738加料线q 进料时乙醇的百分数x=37.7% rF=4.74510437.723.31537.75.3797102413.7kcalKg90883.7KJKmol查表得ts=83.4 tF=(44.242.240.340.6)441.82cPF1.01(3.1949lg37.75.509937.