一、源代码

function [Psum,h,V_gas,detap,P]=boreholepressure(Q_liquid)

Q_liquid=1;

%%%------------------------基础参数-----------------------------

p_stand=0.101325;

T_stand=273.15; %热力学温度

density_gas_stand=1.25/1000;

V_stand=0.022414;

T0=293;

Gt=2.84;

%%%%———————————————井身结构———————————————

H=43860;

H_1=1800 %%开始造斜

H_2=2634 %造斜结束

d_bore =244.5; %%技术套管

d_piple=127;

d_bore_1=215.9;%%三开井眼直径

d_collar=127; %177.8mm

L_collar=150;

%-----------------------钻井参数--------------------------------------

%Q_liquid=25;

Q_gas=111;

visocity_liquid=40; %%mpa s

visocity_gas=25;

Yp=8; %pa

density_mud=1.48;

deta_H=20;

N=H/deta_H;

Tg=zeros(N+1,1);

%------------------注气量----------------

Ratio_gas=Q_gas/Q_liquid;

p_gas=zeros(N+1,1);V_gas=zeros(N+1,1);;density_mix=zeros(N+1,1);

visocity_mix=zeros(N+1,1);Q_mix=zeros(N+1,1);detap=zeros(N+1,1);

v=zeros(N+1,1);Re=zeros(N+1,1);h=zeros(N,1);

%----------------------生产井眼温度和静液柱压力剖面----------------------------------

for i =1:N+1

if i>1 && i<=H_1/deta_H+1

Tg(i,1)=T0+(i-1)*deta_H*Gt/100;

p_gas(i,1)=(i-1)*deta_H*9.8*density_mud/1000; %%单位兆帕MPa

elseif i>H_1/deta_H+1 && i<=H_2/deta_H+1

Tg(i,1)=Tg(H_1/deta_H+1,1)+39.2*(i-(H_1/deta_H+1))*Gt/100;

p_gas(i,1)=9.8*density_mud/1000*H_1+12.7*(i-(H_1/deta_H+1))*9.8*density_mud/1000; %%单位兆帕MPa

V_gas(i,1)=1/(1+p_gas(i,1)*T_stand/(Ratio_gas/p_stand/Tg(i,1)));

elseif i>H_2/deta_H+1 && i<=N+1

Tg(i,1)=T0+(H_1+636)*Gt/100;

p_gas(i,1)=(H_1+636)*9.8*density_mud/1000; %%单位兆帕MPa

end

end

%---------------------计算气体浓度和混合物密度---------------------------

for i=1:N+1

V_gas(i,1)=1/(1+p_gas(i,1)*T_stand/(Ratio_gas*p_stand*Tg(i,1)));

density_mix(i,1)=density_mud*(1-V_gas(i,1))+V_gas(i,1)*density_gas_stand*p_gas(i,1)*T_stand/Tg(i,1)/p_stand;

end

%---------------------计算混合物粘度及混合物粘度---------------------------------------

for i=1:N+1

if V_gas(i,1)>0 && V_gas(i,1)<=0.54

visocity_mix(i,1)=visocity_liquid*(1+3.6*V_gas(i,1));

elseif V_gas(i,1)>0.54 && V_gas(i,1)<=0.96

visocity_mix(i,1)=visocity_liquid/(1-V_gas(i,1)^0.49);

else

visocity_mix(i,1)=visocity_gas*(1+2.5*(1-V_gas(i,1)));

end

Q_mix(i,1)=(1+Ratio_gas*p_stand*Tg(i,1)/T_stand/p_gas(i,1))*Q_liquid;

end

%-------------------------计算环空返速与雷诺数--------------------------

for i=1:N+1

if i>0 && i<=H_2/deta_H+1

v(i,1)=Q_mix(i,1)/(d_bore^2-d_piple^2)/3.14*4*1000; %%%%单位 m/s;

Re(i,1)=density_mix(i,1)*v(i,1)*(d_bore-d_piple)/visocity_mix(i,1)*1000;

elseif i>H_2/deta_H+1 && i<=(H-L_collar)/deta_H+1

v(i,1)=Q_mix(i,1)/(d_bore_1^2-d_piple^2)/3.14*4*1000;

Re(i,1)=density_mix(i,1)*v(i,1)*(d_bore_1-d_piple)/visocity_mix(i,1)*1000;

else

v(i,1)=Q_mix(i,1)/(d_bore_1^2-d_collar^2)/3.14*4*1000;

Re(i,1)=density_mix(i,1)*v(i,1)*(d_bore_1-d_collar)/visocity_mix(i,1)*1000;

end

end

%---------------------------计算摩阻系数------------------------------

f=zeros(N+1,1);

for i=1:N+1

if i>0 && i<=H_2/deta_H+1

ypsl=2*0.5/d_bore;

if Re(i,1)<=2000 %%层流区

f(i,1)=64/Re(i,1);

elseif Re(i,1)>2000 && Re(i,1)<=59.7/ypsl^(8/7) %%水力光滑区

f(i,1)=0.3164/(Re(i,1)^0.25);

elseif Re(i,1)>59.7/ypsl^(8/7) && Re(i,1)<=(665-765 *log(ypsl))/ypsl %%混合摩擦区

f(i,1)=1/(-1.8*(log(6.8/Re(i,1)+(0.5/(3.7 * d_bore))^1.11)/log(10)))^2;

elseif Re(i,1)>((665-765*(log(ypsl)/log(10)))/ypsl)

f(i,1)=1/(2*(log(3.7*d_bore/0.5)/log(10)))^2;

end

else

ypsl=2*1/d_bore_1;

if Re(i,1)<=2000 %%层流区

f(i,1)=64/Re(i,1);

elseif Re(i,1)>2000 && Re(i,1)<=59.7/ypsl^(8/7) %%水力光滑区

f(i,1)=0.3164/(Re(i,1)^0.25);

elseif Re(i,1)>59.7/ypsl^(8/7) && Re(i,1)<=(665-765 *log(ypsl))/ypsl %%混合摩擦区

f(i,1)=1/(-1.8*(log(6.8/Re(i,1)+(1/(3.7 * d_bore_1))^1.11)/log(10)))^2;

elseif Re(i,1)>((665-765*(log(ypsl)/log(10)))/ypsl)

f(i,1)=1/(2*(log(3.7*d_bore_1/1)/log(10)))^2;

end

end

end

%------------------------计算环空摩擦压降----------------------

for i=1:N+1

if i>0 && i<=H_2/deta_H+1

detap(i,1)=2*f(i,1)*density_mix(i,1)*deta_H*v(i,1)^2/(d_bore-d_piple);

elseif i>H_2/deta_H+1 && i<=(H-L_collar)/deta_H+1

detap(i,1)=2*f(i,1)*density_mix(i,1)*deta_H*v(i,1)^2/(d_bore_1-d_piple);

else

detap(i,1)=2*f(i,1)*density_mix(i,1)*deta_H*v(i,1)^2/(d_bore_1-d_collar);

end

end

%%---------------------------计算井筒压力剖面--------------------------------------

三、备注

标签：ypsl,log,油气井,gas,315,Re,zeros,Matlab,&&

来源： https://blog.csdn.net/m0_54742769/article/details/114436182