《工程流体力学》课后习题答案
孔珑第四版
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第2章流体及其物理性质 ............................................................................................................... 4
2-1 ............................................................................................................................................. 4 2-3 ............................................................................................................................................. 4 2-4 ............................................................................................................................................. 6 2-5 ............................................................................................................................................. 6 2-6 ............................................................................................................................................. 6 2-7 ............................................................................................................................................. 7 2-8 ............................................................................................................................................. 7 2-9 ............................................................................................................................................. 8 2-11 ........................................................................................................................................... 8 2-12 ........................................................................................................................................... 9 2-13 ........................................................................................................................................... 9 2-14 ......................................................................................................................................... 10 2-15 ......................................................................................................................................... 10 2-16 ......................................................................................................................................... 11 第3章 流体静力学 ....................................................................................................................... 12
3-1 ........................................................................................................................................... 12 3-2 ........................................................................................................................................... 12 3-3 ........................................................................................................................................... 13 3-5 ........................................................................................................................................... 13 3-6 ........................................................................................................................................... 14 3-9 ........................................................................................................................................... 14 3-10 ......................................................................................................................................... 15 3-21 ......................................................................................................................................... 18 3-22 ......................................................................................................................................... 19 3-23......................................................................................................................................... 20 3-25 ......................................................................................................................................... 20 3-27 ......................................................................................................................................... 20 第4章 流体运动学及动力学基础 .............................................................................................. 22 4-2 ........................................................................................................................................... 22 4-5 ........................................................................................................................................... 22 4-6 ........................................................................................................................................... 23 4-8 ........................................................................................................................................... 23 4-11 ......................................................................................................................................... 24 4-12 ......................................................................................................................................... 24 4-14 ......................................................................................................................................... 25 4-22 ......................................................................................................................................... 25 4-24 ......................................................................................................................................... 26 4-26 ......................................................................................................................................... 27 第6章作业..................................................................................................................................... 28
6-1 ........................................................................................................................................... 28 6-3 ........................................................................................................................................... 28 6-7 ........................................................................................................................................... 29
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6-10 ......................................................................................................................................... 29 6-11 ......................................................................................................................................... 29 6-12 ......................................................................................................................................... 30 6-17 ......................................................................................................................................... 31
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第2章流体及其物理性质
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已知某种物质的密度ρ=2.94g/cm3，试求它的相对密度d。【2.94】 解：ρ=2.94g/cm3=2940kg/m3，相对密度d=2940/1000=2.94
2-2已知某厂1号炉水平烟道中烟气组分的百分数为，α(CO2)=13.5%α(SO2)=0.3%，α(O2)=5.2%，α(N2)=76%，α(H2O)=5%。试求烟气的密度。
解：查课表7页表2-1，可知ρ(CO2)=1.976kg/m3，ρ(SO2)=2.927kg/m3，ρ(O2)=1.429kg/m3，ρ(N2)=1.251kg/m3，ρ(H2O)=1.976kg/m3，ρ(CO2)=1.976kg/m3，
????i?i?1.341kg/m3
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上题中烟气的实测温度t=170℃，实测静计示压强Pe=1432Pa，当地大气压Pa=100858Pa。试求工作状态下烟气的密度和运动粘度。 【0.8109kg/m3，2.869×10-5㎡∕s】 解：
1）设标准状态下为1状态，则p1=101325pa，T1=273K，ρ1=1.341kg/m3 工作状态下为2状态，则p2=pa-pe=100858-1432=99416pa，T2=273+170=443K，
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