1 内容介绍
油气井流入动态是确定油气井合理工作制度及动态分析的基础,对于溶解气驱油藏,油气井流入动态呈非线性,目前常用IPR曲线计算压力与产量的关系.
2 部分代码
% function [Psum,h,V_gas,detap,P]=boreholepressure(Q_liquid)
clc
clear all
close all
Q_liquid=5;
%%%------------------------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=1850 %%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=5;
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--------------------------
P=zeros(N,1);
for i=2:N
P(i,1)=sum(detap(2:i));
end
figure(2)
plot(P)
title('井筒压力剖面')
3 运行结果
