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1、序号累计时间(分)总重量GT(g)干基含水量X(kg/kg)平均含水量XAV(kg/kg)干燥速率Ux104kg/(sm2)10108.62.0572.01593.123323107.31.9751.93632.883036106.11.8981.86312.6428491051.8281.79622.40255121041.7641.73252.40256151031.7011.67202.1623718102.11.6431.61462.1623821101.21.5861.55732.1623924100.31.5291.50002.1623102799.41.4711.44272.16
2、23113098.51.4141.38542.1623123397.61.3571.32802.1623133696.71.2991.27072.1623143995.81.2421.21342.1623154294.91.1851.15612.16231645941.1271.09872.1623174893.11.0701.04142.1623185192.21.0130.98412.1623195491.30.9550.92682.1623205790.40.8980.86942.1623216089.50.8410.81212.1623226388.60.7830.75801.9220
3、236687.80.7320.70701.92202469870.6820.65921.6818257286.30.6370.61461.6818267585.60.5920.56691.9220277884.80.5410.51591.92202881840.4900.46821.6818298483.30.4460.42361.6818308782.60.4010.38221.44153190820.3630.34711.2013329381.50.3310.31850.9610339681.10.3060.28981.2013349980.60.2740.25801.2013351028
4、0.10.2420.22930.96103610579.70.2170.20061.20133710879.20.1850.16881.20133811178.70.1530.14010.96103911478.30.1270.11460.96104011777.90.1020.08920.96104112077.50.0760.06690.72084212377.20.0570.04780.72084312676.90.0380.03180.48054412976.70.0250.01910.48054513276.50.0130.00640.48054613576.3干燥实验数据整理表设备
5、编号:1#空气孔板流量计读数R(KPa)流量计处空气温度to(C)0.5干球温度t(C)48.8湿球温度tw(C)twC下水的气化热(kJ/kg)Ytwto(C)空气密度P(Kg/m3)1.11流量计孔流系数C00.65洞道截面积(m2)=0.13*0.17孔板孔径d0(m)0.04干燥面积(m2)S=0.141*0.082*2框架重量GD(g)60.6绝干物料量GC:(g)对流传热系数a(w/m2C)=干燥器内空气实际体积流量Vt(m3/s)=干燥器内空气流速u(m/s)=604026000.02210.02312415.740.600.02541.1477二3XarQg/Eg)计算实例:空
6、气物理性质的确定:流量计处空气温度to=48.8(C),查表得空气密度P=l.ll(Kg/m3)湿球温度tw=40(C),twC下水的气化热(kJ/kg)Ytw=2600。以第一组数据为例1、计算干基含水量X=(总重量GT-框架重量GD-绝干物料量GC)/绝干物料量GC=(l08.6-60.6-l5.7)/l5.7=2.057(kg/kg)2、计算平均含水量XAV=两次记录之间的平均含水量=(2.057+1.975)/2=2.0159(kg水/kg绝干物料)3、计算干燥速率U=-(绝干物料量GC/干燥面积S)*(X/T)=-(15.7*0.001/0.023124)*(1.975-2.057)
7、/(3*60)=0.0003123kg/(sm2)4、绘制干燥曲线(XT曲线)和干燥速率曲线(UXAV曲线)Uc*r*10005、计算恒速干燥阶段物料与空气之间对流传热系数aW/m2C,二twttwUc恒速干燥阶段的干燥速率,kg/(m2s)=0.0002162YtwtwC下水的气化热,kJ/kg。查表P351,tc-t=374-40=334C.查表得,Ytw=2600a=2.162*0.0001*2600*1000/(60-40)=28.116、计算干燥器内空气实际体积流量Vt(m3/s)。V=Vtt0273+1273+10=0.0245*273+60273+48.8其中:=0.254Vt0t0C时空气的流量,m3/s;V=CAt0002p=0.65*0.001256*P2*5001.11=0.0245t0流量计处空气的温度,t0=48.8C;t干燥器内空气的温度,t=60C;C0流量计流量系数,C0=0.6;兀314A二一d2二*0.042二0.001256A0流量计孔节孔面积,m2。0404d0孔板孔径,d0=0.04moAP流量计压差,AP=500Pa。Pt0时空气密度kg/m3,P=1.11o7、计算干燥器内空气流速U(m/s)。U=Vt/A=0.0254/0.0221=1.1477(m/s)。其中:A洞道截面积(m2)A=0.13*0.17=0.0221(m2)