【阳光原创首发】关于流线模拟器中最常见的问题：high material balance errors的解决

joylin

浅谈流线模拟器中最常见的问题：high material balance errors的解决办法：

①Eclipse的Frontsim流线模拟器采用IMPES求解方法。优点是速度快，缺点是稳定性差,尤其是锥进问题以及过泡点问题不能很好解决。因此时间步长不能太大。在出现highmaterial balance errors时，可以适当减小时间步。这个问题一般出现在预测中使用TSTEP关键字，时间步过大。

②既然是物质平衡错误，那么涉及的主要参数就是油水气高压物性、产出量、注入量等参数。

产出、注入参数一般定位准确值，所以主要检查高压物性参数，比如B、C、Rs等。值得注意的是PVTW中的第三项水的压缩系数比较容易被忽略，造成错误，注意其范围一般为3.5e-4~5.0e-4 MPa-1 。

③如果上述方法无效，可以在SCHEDULE部分使用TUNEFSPR关键字，增大模拟器允许的最大物质平衡错误。

TUNEFSPR关键字第二项参数为Maximum material balance error，默认值是0.02。可以增大此值（比如0.2）来解决high material balance errors。

以下是Frontsim TD手册中关于三相模型high material balance errors的解决办法（效果不是很好，供参考）：

3-phase data sets frequently need tuning. The most common problems are simulations stopping due to high material balance errors or unphysical solution values. These can often be solved by one of the following.
1     Increasing the number of Newton iterations that can be used in each mini time-step in the saturation solver - item 12 of TUNEFS1D. Values above 12 rarely provide any benefit.2     Decreasing the minimum size of the mini time-step allowed in the saturation solver. This is controlled using item 4 of keyword TUNEFS1D; it is a multiple of the actual time step. It s unlikely that a value which corresponds to a mini time-step of less than 0.5 days will help.3     Decreasing the time step may help with problems.4     Ensuring that the initial pressure solve has converged also can overcome problems with 3-phase simulations. This can often be done by increasing the number of Newton iterations in the pressure solver. This is controlled by item 5 of keyword TUNEFSSA.
In each case there is a cost in terms of the simulator performance. The user can however apply the change just before the point at which the problem occurs. It is worth noting that problems often only appear 1 or 2 time steps after the actual problem has occurred, so it is can be effective to apply these tuning changes 3 or 4 time steps before the observed problem.
本人水平有限，不正之处请斧正，欢迎大家讨论！

一城风絮

@阳光顾问@超级版主@版主多谢给力的楼主！！流线模拟技术是黑油模拟技术的有力补充，特别对于水驱油过程的流线定量模拟和追踪具有无可比拟的优势。
楼主，请问您对组分流线模拟器有研究吗？希望能进一步向你深入讨教！

joylin

一城风絮 发表于 2012-5-3 22:57
@阳光顾问@超级版主@版主多谢给力的楼主！！流线模拟技术是黑油模拟技术的有力补充，特别对于水驱油过程的流 ...

讨教不敢，很遗憾，我是一年时间业余学习。组分模型还未接触，不过很感兴趣，看来得请教你了

一城风絮

joylin 发表于 2012-5-3 23:00
讨教不敢，很遗憾，我是一年时间业余学习。组分模型还未接触，不过很感兴趣，看来得请教你了

别太谦虚了哈，呵呵，一直关注您！！

hanz

很感兴趣,老大赶紧出了视频哈,让大家学习学习

chutianshu

支持一下

chutianshu

谢谢楼主分享

dragon

请问楼主这个问题怎么解决呢？
FRONT-SIM_FRONT


ERRORS and WARNINGS :

--Warning at time 1 May 2010 step 0:
          Defaulting summary control to 2005a

--Warning at time 1 May 2010 step 0:
          The maximum water saturation in SWFN/SWOF table no 1 is less than 1.0 (0.736000)
          This should normally be 1.0 unless initial water saturations
          are to be restricted to this value
--Warning at time 1 May 2010 step 0:
           TRACK ordering inappropriate for Z1       - using DEPTH instead (see keyword COMPORD)
           TRACK ordering inappropriate for Z2       - using DEPTH instead (see keyword COMPORD)
           TRACK ordering inappropriate for Z3       - using DEPTH instead (see keyword COMPORD)
           TRACK ordering inappropriate for Z4       - using DEPTH instead (see keyword COMPORD)
           TRACK ordering inappropriate for Z5       - using DEPTH instead (see keyword COMPORD)
           TRACK ordering inappropriate for Z6       - using DEPTH instead (see keyword COMPORD)

wanghao88

真的解决了，高手啊