The pressure response during a well test provides important information about reservoir properties, well productivity or reservoir performance. In order to have an option to replace traditional production tests, avoiding the gas flaring and increasing operational safety, injectivity test began to play an important role in the management of reservoirs. Although analytical models are able to describe injection and falloff periods, multiple rate models still need to be developed. This work presents a new formulation to compute pressure response when performing multiple rate injectivity test in a water injection well operating in an oil zone. First, the proposed formulation is compared to injection/falloff models and after a multiple rate scheme is performed. This formulation extends prior models presented in the literature. The accuracy of the proposed solution was assessed by comparison with a numerical simulator. The proposed formulation is also used to determine the reservoir equivalent permeability in any specific period of injection or shut-in.

中文翻译：

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多次注入测试中压力行为的近似解决方案

试井期间的压力响应可提供有关储层特性，井产能或储层性能的重要信息。为了能够替代传统的生产测试，避免产生天然气并提高操作安全性，注入测试在储层管理中开始发挥重要作用。尽管分析模型能够描述注入和下降期，但仍需要开发多种速率模型。这项工作提出了一种新的公式，可以在在油层中运行的注水井中执行多次注入测试时计算压力响应。首先，将提出的配方与注入/衰减模型进行比较，然后执行多重速率方案。这种表述扩展了文献中提出的现有模型。通过与数值模拟器进行比较，评估了所提出解决方案的准确性。所提出的公式还可以用于确定在任何特定的注入或关闭时期内的储层等效渗透率。