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本法主要公式如下: ∑△/△_1=1+U_1A_1/U_2A_2+U_1A_1/U_3A_3(11) λ_(av)=FC_F(t_(L_1)-tF)/∑E+λ_(L_1)/b(10) U_1/U_(av)=(1+R_2+R_3……/n) (1+U_1/U_2R_2+U_1/U_3R_3……)(14) λ_(av)∑E=U_(av)∑△∑A(16)由(16)可演算成(16a),(16b)或(16c) q_1=∑E[λ_(av)-((n-1)/n)λ_(L_1)](17) S=q_1/λs(18) 解此等公式时可按上列顺序。若干举例将正确法与简化法作一对照,证明简化法确实简单省时。本法可应用于顺流,逆流及错流加料法中。本法不能应用于多效蒸发器中有取出额外蒸汽的情况。辐射热损失的计算可在本法计算完了后再进行。本法的正确度在一般化学工程上已足够应用。本法应用在典型的蒸发问题上以作传热面,蒸汽消耗,或容量的计算。共误差约2%。经作者数年内在各种蒸发问题上应用本法计算,其最大误差为7.5%。
The main law of this law is as follows: Σ △ / △ _1 = 1 + U_1A_1 / U_2A_2 + U_1A_1 / U_3A_3 λ_av = FC_F t_L_1 -tF / ΣE + λ_ (L_1) / b U 1 / U av = 1 + R 2 + R_3 ... / n 1 + U_1 / U_2R_2 + U_1 / U_3R_3 ... λ_ av ΣE = U_av ΣΔΣA (16) can be calculated from (16) as (16a), (16b) or (16c) q_1 = ΣE [λ_ (av) - ((n-1) / n) λ_ (L_1) q_1 / λs (18) Solution of these formulas can be in the order listed above. A number of examples compare the correct method with the simplified method to prove that the simplified method is indeed simple and time-saving. This method can be applied to downstream, countercurrent and cross-flow feeding method. This Act can not be used in multi-effect evaporators where extra steam is removed. Calculation of radiant heat losses may be made after the calculation of this Act has been completed. The correctness of this law has been applied adequately in general chemical engineering. This law applies to typical evaporation problems for heat transfer surfaces, steam consumption, or capacity calculations. A total of about 2% error. By the author within a few years on the various evaporation problems calculated using this method, the maximum error of 7.5%.