预热器传热计算

热管空气预热器计算(6)热管空气预热器计算传热计算广州溶剂脱沥青回收脱沥青油加热炉烟气160x104kcal/h按照热端3100，冷端：2400项目项目项目计算公式及图表数值管子选取φ42*3.5*25001.管子外径d0m给定0.0422.管子内径dim给定0.0353.翅片高度bm给定0.0154.翅片间距(烟气侧)dpm已知0.006翅片间距(空气侧)dpm已知0.0045.翅片厚度dmm已知0.0016.翅片管有效长度(烟气侧)Lhm已知3.1翅片管有效长度(空气侧)Lcm已知2.47.每排管根数nw根已知279.管排数Zz排已知1410.管心距S1m已知0.08511.排心距S2m已知0.08512.空气流量Wakg(air)/h已知4014613.烟气流量Wgkg(gas)/h已知3550014.空气入口温度to℃已知15.615.空气出口温度tm℃已知17716.烟气入口温度t1℃已知33017.烟气出口温度t2℃已知17018.空气平均温度ta'℃ta'=(t0+tm)/296.3TaKTa=ta'+273369.319.烟气平均温度tg'℃tg'=(t1+t2)/2250TgKTg=tg'[phone].对数平均温差Δt℃Δt=((t1-tm)-(t2-to))/ln((t1-tm)/(t2-to))153.698937321.预热器净宽SmS=S1*(nw-1)+d0+2*b+0.042.322热管空气预热器空气侧的外膜传热系数按以下计算22.每米翅片管所占的流通面积acm2/mac=d0+2*b*dm/dp0.049523.空气质量流速Gakg/m2.sGa=Wa/(3600*Lc*(S-nw*ac))4.714893737第1页热管空气预热器计算(6)24.每米光管外表面积aom2/mao=pi()*d00.13194689125.每米翅片管的翅片表面积afm2/maf=pi()/4*((do+2*b)^2-d0^2)*2/dp1.34303085926.光管外膜传热系数hocKW/m2.℃0.052297374Xb*((2*hoc)/(λ*dm))^0.50.71997641727.翅片效率Ωf无因次Ωf=((exp(x)-exp(-x))/(exp(x)+exp(-x)))/x0.85682625228.包括结垢热阻的光管外膜传热系数hoc*KW/m2.℃hoc*=1/(1/hoc+Ri)0.051373156Rim2.℃/KW0.34429.翅化率ββ=(Ωf*af+a0)/a09.721267205接触数φ0.8530.翅片管的外膜传热系数(空气侧)hfKW/m2.℃hf=hoc**β*Φ0.424500347热管空气预热器烟气侧的外膜传热系数按以下计算22.每米翅片管所占的流通面积acm2/mac=d0+2*b*dm/dp0.04723.烟气质量流速Ggkg/m2.sGg=Wg/(3600*Lh*(S-nw*ac))3.02089609124.每米光管外表面积aom2/mao=pi()*d00.13194689125.每米翅片管的翅片表面积afm2/maf=pi()/4*((do+2*b)^2-d0^2)*2/dp0.89535390626.光管外膜传热系数hocKW/m2.℃0.043138139Xb*((2*hoc)/(λ*dm))^0.50.65389652927.翅片效率Ωf无因次Ωf=((exp(x)-exp(-x))/(exp(x)+exp(-x)))/x0.87825399828.包括结垢热阻的光管外膜传热系数hoc*KW/m2.℃hoc*=1/(1/hoc+Ri)0.036388323Rom2.℃/KW烧气4.3m2.℃/KW烧油8.629.翅化率ββ=(Ωf*af+a0)/a06.959580698接触数φ0.8530.翅片管的外膜传热系数(烟气侧)hfKW/m2.℃hf=hoc**β*Φ0.215260351热管空气预热器内膜传热系数31.烟气侧内膜传热系数hi'kw/m2.℃查72B002-93P302.907532.空气侧内膜传热系数hi''kw/m2.℃查72B002-93P304.0705热管空气预热器的总传热系数hoc=10.98*Ga^0.667*Tg^0.3/do^0.333*power(10,-4)hoc=10.98*Gg^0.667*Tg^0.3/do^0.333*power(10,-4)第2页热管空气预热器计算(6)33.烟气侧的总传热系数Khkw/m2.℃Kh=1/(1/hf+1/hi'+Rt)0.197090581平均温度下的导热系数λkw/m.℃查72B002-93P330.0454管壁热阻Rtm2.℃/KwRt=do/(2*λ)*ln(do/di)0.0843337634.空气侧的总传热系数Kckw/m2.℃Kc=1/(1/hf+1/hi''+Rt)0.372340396平均温度下的导热系数λkw/m.℃查72B002-93P330.0454管壁热阻Rtm2.℃/KwRt=do/(2*λ)*ln(do/di)0.08433376按热管全部外表面积计算的总传热系数交错排列Kkw/m2.℃K=1/(1/Kh*L/Lh+1/Kc*L/Lc)0.06597750156.74065103正方形排列K'kw/m2.℃K=0.8*K'0.03958650134.0443906239.烟气比热Cp'KJ/kg.℃查72B002-93P111.1107540.空气吸热量QakwQa=0.94*Wg*Cp'*(t1-t2)/36001647.36566741.传热面积Fm2F=Qa/(K'*Δt)270.752223642.管排数Zz排Zz=F/(pi()*L1*nw*do)13.81803904压降计算(管外侧压降)计算方法参考化学工业炉设计手册P4531.管子翅化系数βF1/F7.904761905翅片管总面积面积F1m2/mF1=1/dp*(2*pi()/4*((d0+2*b)^2-d0^2))+pi()*(do+2*h)*dm+pi()*do*(dp-dm))1.043008761光管面积Fm2/mF=do*pi()0.1319468912圆形翅片管管长(假设条件)lml=((dp-dm)*1/dp*do)/β+0.5*1/dp*((do+2*b)^2-do^2)/(d0*β)*(0.785*((do+2*b)^2-0.0507794733.翅片管当量直径DemDe=2*(dp*(S1-do)-2*dm*b)/(2*b+dp)0.0126666674.烟气平均温度下密度γgkg/m3354/Tg0.6768642455.烟气平均温度下的粘度μcp查图7-200.036.烟气流速ωm/sWgas/(3600*S*γg)4.4630752997.雷诺数Re1000*ω*γg*l/μ5113.3170258.阻力系数ζζ0*Zz5.576258719一排管子的阻力系数ζ0cs*cn*Re^(-0.08)0.398304194管束排数的修正系数Cn参P4551顺列管束的形状系数Cs0.52*(l/de)^0.3*Ψ^-0.680.78869865Ψ(s1-d0)/(s2-d0)19.管束阻力mmH2oζ*ω2/(2*9.81)*γ3.831897766第3页热管空气预热器计算(6)第4页热管空气预热器计算(6)第5页热管空气预热器计算(6)kcal/m2.h.℃kcal/m2.h.℃第6页板式预热器计算板式空气预热器计算传热计算广州溶剂脱沥青回收脱沥青油加热炉烟气项目项目项目计算公式及图表数值板式预热器单体1mx1mx1m1.空气侧单孔面积S1m2给定0.012.烟气侧单孔面积S2m2给定0.013.空气侧孔数n1个给定1004.烟气侧孔数n2个给定2005.空气流通长度L1m给定26.烟气流通长度L2m给定17.空气流量Wakg(air)/h已知401398.烟气流量Wgkg(gas)/h已知288409.空气入口温度to℃已知15.610.空气出口温度tm℃已知12711.烟气入口温度t1℃已知33012.烟气出口温度t2℃已知17013.空气平均温度ta'℃ta'=(t0+tm)/271.3TaKTa=ta'+273344.314.烟气平均温度tg'℃tg'=(t1+t2)/2250TgKTg=tg'[phone].对数平均温差Δt℃Δt=((t1-tm)-(t2-to))/ln((t1-tm)/(t2-to))177.5930606板式空气预热器空气侧的外膜传热系数按以下计算1空气的定性温度℃71.3定压比热cpKJ/kg.℃1.009导热系数λW/m.℃0.0297粘度μkg/m.s0.0000206密度ρkg/m31.0292.当量直径dem4×流通截面积/浸润周边长度0.019801983.空气线速υm/s10.835492934.雷诺数ReRe=d*u*ρ/μ10717.795085.普兰特准数PrPr=cp*μ/λ0.6998451186.努塞尔特准数NuNu=0.023*Re0.8*Pr0.433.40511494第7页板式预热器计算7.空气侧的的对流传热系数hocW/m2.℃hoc=λ/de*Nu50.10266164空气侧的热阻Rim2.℃/W0.0003448.包括结垢热阻的光管外膜传热系数hocair*W/m2.℃hoc*=1/(1/hoc+Ri)49.25375758板式空气预热器烟气侧的外膜传热系数按以下计算1烟气的定性温度℃250定压比热cpKJ/kg.℃1.145导热系数λW/m.℃0.03942粘度μkg/m.s0.00002519密度ρkg/m30.651222.当量直径dem4×流通截面积/浸润周边长度0.019801983.烟气线速υm/s6.1508484934.雷诺数ReRe=d*u*ρ/μ3148.7864945.普兰特准数PrPr=cp*μ/λ0.7316730096.努塞尔特准数NuNu=0.0359*Re0.816*Pr0.313.168536677.烟气侧的的对流传热系数hocW/m2.℃hoc=λ/de*Nu26.21473764烟气侧的热阻Rim2.℃/W0.00868.包括结垢热阻的光管外膜传热系数hocgas*W/m2.℃hoc*=1/(1/hoc+Ri)21.39198441板式空气预热器的总传热系数1总传热系数KW/m2.℃K=hocair*Xhocgas*/(hocair*+hocgas*)14.91435414板式空气预热器的负荷1.烟气比热Cp'kcal/kg.℃0.262.烟气放热Qgaskcal11997443.传热面积Fm2F=Qa/(K'*Δt)619.7534212空气侧压降1.雷诺数ReRe=d*u*ρ/μ10717.79508摩擦因数λ化工原理P49图1-300.03第8页板式预热器计算ΔPmmH2OΔP=λ*L/De*ρ*υ2/(2*9.8)18.6766628压降计算烟气侧压降1.雷诺数ReRe=d*u*ρ/μ3148.786494摩擦因数λ化工原理P49图1-300.025ΔPmmH2OΔP=λ*L/De*ρ*υ2/(2*9.8)1.586986034第9页热管空气预热器计算(5)热管空气预热器计算传热计算广州溶剂脱沥青回收脱沥青油加热炉烟气120x104kcal/h按照热端3100，冷端：2400项目项目项目计算公式及图表数值管子选取φ42*3.5*25001.管子外径d0m给定0.0422.管子内径dim给定0.0353.翅片高度bm给定0.0154.翅片间距(烟气侧)dpm已知0.007翅片间距(空气侧)dpm已知0.0045.翅片厚度dmm已知0.0016.翅片管有效长度(烟气侧)Lhm已知3.1翅片管有效长度(空气侧)Lcm已知2.47.每排管根数nw根已知279.管排数Zz排已知1410.管心距S1m已知0.08511.排心距