\[Mu]g = 0.000018, \[Rho] = 2700, Cc = 1, R = 0.076, Rw = 0.153, P = \
0.144, T = 0.184*pi, v = 17.986;
Dpc = \[Sqrt]((18 \[Mu]g/\[Rho]/Cc/v/\[Theta])*((1 +
P) Rw*0.5 ((r/Rw)^2 - (R/Rw)^2) (1 +
P) Rw*((r/Rw)^3 - (R/Rw)^3)/3));
f1 = PDF[NormalDistribution[1.625, 0.7324], {-Log[Dpc], Infinity}];
f2 = 0.005*(1 - f1);
f3 = NIntegrate[f2*r, {r, R, Rw}];
r = Rw;
f11 = f1;
f22 = 0.005*(1 - f11);
f4 = NIntegrate[f22*Rw/f1, {\[Theta], 0, T}]

\[Mu]g = 0.000018; \[Rho] = 2700; Cc = 1; R = 0.076; Rw = 0.153; P = \
0.144; T = 0.184*pi; v = 17.986;
Dpc = \[Sqrt]((18 \[Mu]g/\[Rho]/Cc/v/\[Theta])*((1 +
P) Rw*0.5 ((r/Rw)^2 - (R/Rw)^2) (1 +
P) Rw*((r/Rw)^3 - (R/Rw)^3)/3));
F1 = CDF[NormalDistribution[1.625, 0.7324], {-Log[Dpc], Infinity}];
F2 = 0.005*(1 - F1);
F3 = NIntegrate[F2*r, {r, R, Rw}];
r = Rw;
F11 = F1;
F22 = 0.005*(1 - F11);
F4 = NIntegrate[F22*Rw/f1, {\[Theta], 0, T}]
自己又改了一下，但结果是一个含Ercf的函数，我想要个数值解

……不要臆测函数的用法。你仔细看看PDF和CDF的自带帮助。