最近我做了一个MEA吸收空气CO2的模拟，但是结果一直难以收敛，希望哥哥姐姐们帮助一下，谢谢了！模型文件已经放在附件中。
【模拟参数】：
1.物性方法：ELECNRTL.
2.物性参数：由于aspen物性集中缺少一些组分的物性，需要手动输入。我在aspen的示例文件中找到了MEA的模拟文件，并且直接沿用他的properties模块，再在simulation模块中设置自己的系统。
3.物流参数：AIR（co2=1%，flowrate=5kmol/s）,LEAN（MEA=0.18kmol/s,H2O=0.915kmol/s,CO2=0.045kmol/s）
4.吸收塔：板式塔，15 stage，筛板，（液相持液量不会算）
【模拟结果（有删减）】：
1.根据outside loop的迭代结果来看，第63步的误差已经小于允许值，按理说应该结束这个循环，但是为什么一直执行200步，误差很明显已经接近于0了，还有warning提示说不能收敛呢？
2.错误类型大概有以下几种：误差无法收敛，能量、质量、电荷数不守恒，这些错误应该如何解决？
->Calculations begin ... Block: ABSORBER Model: RADFRAC Convergence iterations: OL ML IL Err/Tol 1 1 10 42.824 2 1 10 36.573 3 1 10 44.952 4 1 10 17.079 ......... 60 1 1 164.09 61 1 1 82.043 62 1 1 41.022 63 1 1 0.60615E-11 64 1 1 0.14303E-10 65 1 1 0.16593E-10 66 1 1 0.69352E-11 ........ 196 1 1 0.38655E-11 197 1 1 0.15827E-10 198 1 1 0.0000 199 1 1 0.16292E-10 200 1 1 0.38655E-11 * WARNING RADFRAC NOT CONVERGED IN 200 OUTSIDE LOOP ITERATIONS. * WARNING MATERIAL AND ENERGY BALANCES FAILED TO CONVERGE: CHECK COL-SPECS OR SUPPLY BETTER TEMPERATURE AND COMPOSITION ESTIMATES. RateSep convergence iterations: ABSORBER Iter Err/Tol 0 0.57784E+19 ** ERROR VARIABLE RESET ENCOUNTERED IN VAPOR MASS TRANSFER CORRELATION CHAN-FAIR-84. THE SUPERFICIAL VAPOER VELOCITY EXCEEDED THE FLOODING VELOCITY. THE FLOODING VELOCITY IS RESET TO 1.07 OF THE SUPERFICIAL VAPOR VELOCITY. THE COLUMN DIAMETER MIGHT BE TOO SMALL. ** ERROR RATESEP CALCULATIONS FAILED TO CONVERGE ITERATIONS DIVERGE ** ERROR BLOCK ABSORBER IS NOT IN MASS BALANCE: MASS INLET FLOW = 0.17399457E+03, MASS OUTLET FLOW = 0.22491972E+03 RELATIVE DIFFERENCE = 0.29268243E+00 ->Generating results ... * WARNING STREAM RICH IS NOT IN CHARGE BALANCE: ANION FLOW = -.23719561E+01, CATION FLOW = 0.29208323E+00 ABSOLUTE DIFFERENCE = -.20798728E+01 RELATIVE DIFFERENCE = -.71208224E+01 INFORMATION WHILE GENERATING REPORT FOR UNIT OPERATIONS BLOCK: "ABSORBER" (MODEL: "RADFRAC") TPSAR MESSAGE: 412.78% JET FLOOD IN COLUMN ABSORBER, SECTION 1 EXCEEDS 80%. INFORMATION WHILE GENERATING REPORT FOR UNIT OPERATIONS BLOCK: "ABSORBER" (MODEL: "RADFRAC") TPSAR MESSAGE: 47865.95% DC BACKUP IN COLUMN ABSORBER, SECTION 1 EXCEEDS 80%. INFORMATION WHILE GENERATING REPORT FOR UNIT OPERATIONS BLOCK: "ABSORBER" (MODEL: "RADFRAC") TPSAR MESSAGE: 106.35% OF SYSTEM LIMIT IN COLUMN ABSORBER, SECTION 1 EXCEEDS 80%. INFORMATION WHILE GENERATING REPORT FOR STREAM: "RICH" (WHILE EVALUATING PROPSET: "XAPP") APPARENT COMPOSITION GENERATION MAY NOT BE UNIQUE FOR CHEMISTRY "MEA" THE ORDER OF REACTIONS WAS USED IN THE GENERATION HEURISTICS.
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