同离子效应和温度场对裂缝中酸液有效作用距离的影响

酸液有效作用距离是酸压设计的重要参数，也是影响酸压效果的重要因素。酸液中的反应产场(同离子)和裂缝中温度分布对酸液沿裂缝流动时的有效作用距离影响很大。到目前为止，尚未见到研究同离子效应和温度场对酸液有效作用距离综合影响的文章。本文从酸压设计计算的实际需要出发，考虑影响酸液有效作用距离的主要因素，建立裂缝中酸岩流动反应数学模型，并将该模型与裂缝中温度分布模型、速度场模型和表面反应动力学模型联立求解，编制电算程序，进行系统计算。分析对比，给出了同离子效应、酸液浓度、地层温度、反应生成热等因素对酸液有效作用距离影响的对比数据和图表。本文所编制的计算机程序和得到的结论可供酸压施工和设计计算使用。

EFFECTS OF TEMPERATRE FIELD AND COMMON ION EFFECT ONEFFECTIVE ACID PENETRATION IN FRACTURE SYSTEMS

The effective acid penetration distance is an important parameter in acid-fracturing treatment design and has treat influence upon the effect of the treatment. The temperature in a fracture and the acid-rock reaction products simultaneously affect the acid penetration greatly. But up to mow, no information concerning this aspect has been published.For satisfying practical requirements of calculation in the treatment design, this paper developes a new mathematical model for reaction of acid flowing in the fracture by taking principal factors affecting the effective penetration of the acid into consideration. This model is combined with the model of temperature distribution in a fracture, the model of velocity field and the model of acid-rock surface reaction kinetics to give their solution simultaneously and a corresponding computer program has been established to give a system calculation. Figures and tables of data on the influences of common ion effect, acid concentration, formation temperature and heat generated by the acid-rock reaction on effective acid penetration distance have been obtained by analyzing and correlating.The computer program and calculations obtained in this paper can be used in practical acid-fracturing treatment design.