化学工程基础 (武汉大学 著) 课后习题答案第二张.pdf

第二章 流体流动与输送 大气压是9.8 4 1、一个工程 1×10 Pa ，一个工程大气压相当于多少毫米汞柱？相当于多少 米水柱？相当于密度为850kg ⋅ m−3 的液体多少米液柱？ 解：已知：ρHg = 13600 kg ⋅ m−3 ρ = 1000 kg ⋅ m−3 H O2 −3 4 ρ = 850 kg ⋅ m ρ = 9.81×10 Pa 料 求：hHg 、h 、h料 H O2 因；P = ρ ⋅ g ⋅ h = ρ ⋅ g ⋅ h = ρ ⋅ g ⋅ h Hg Hg H O2 H O2 料 料 4 P 9.81 10 × 所以：hHg = 0.735mHg = 735mmHg ρ ⋅ 13600g 9.81 × Hg 4 P 9.81 10 × h = 10.0mH O H O 2 2 ρ ⋅ 1000g 9.81 × H O2 4 P9.81 10 × h料 = 11.8m 液柱 ρ ⋅ 850g 9.81 × 料 2 、一个物理大气压是760 毫米汞柱，问其相当于多少Pa ？相当于多少米水柱？ 解：因P = ρHg ⋅ g ⋅ hHg = ρ ⋅ g ⋅ h H O2 H O2 ρ ⋅h × 13600 0.760 Hg Hg 所以：h = 10.33mH O 2 H O2 ρ 1000 H O2 5 P = h ⋅ρ ⋅ g = 13600 × 0.760 × 9.81 = 1.013 × 10 Pa Hg Hg