高频电磁加热稠油储层温度分布及其影响因素分析

为了准确分析高频电磁加热过程中影响稠油储层温度分布的因素，以电磁场和传热理论为基础，考虑稠油储层电导率、相对介电常数随频率变化，导热系数、比热容随温度变化的实际情况，建立了描述储层性质动态变化的数学模型，并采用多物理场模拟软件COMSOL求解数学模型，采用对比法分析了不同因素对温度分布的影响规律。计算分析发现:电磁波功率的提高有助于增大储层加热深度；较大的电磁波频率可引起波源附近储层温度升高，但温度随深度增大急剧下降；考虑储层性质动态变化时计算出的温度分布，与假设储层性质恒定时的计算结果存在差异；在一定变化范围内，储层温度值随相对介电常数和电导率增大而增大。研究结果表明，储层性质、电磁波功率和频率对储层的温度分布有明显影响，建立的考虑储层性质动态变化的数学模型为高频电磁加热稠油技术的现场应用提供了理论依据。 

Temperature Distribution of Heavy Oil Reservoirs under High Frequency Electromagnetic Heating and an Analysis of Its Influencing Factors

In order to accurately analyze the factors affecting the temperature distribution of heavy oil reservoirs during high frequency electromagnetic heating, a mathematical model with dynamically varied reservoir properties was established based on the theories of electromagnetic field and heat transfer. In this model, frequency dependence of electrical conductivity and the relative permittivity of heavy oil reservoirs were taken into consideration, along with the temperature dependence of thermal conductivity and specific heat. In addition, COMSOL software of was employed to develop a mathematical model. Finally, the influencing laws governing temperature variation factors were studied by a contrast method. The calculations reflect a direct correlation between electromagnetic wave power and reservoir heating depth, and they demonstrate that the increase of electromagnetic wave power helps to increase the heating depth of reservoir. Although large electromagnetic wave frequency can lead to high temperature area nearby the wave source, the temperature value decreases sharply with the increase of depth. The results of a temperature calculation considering the dynamic change of reservoir properties differ from those calculated based on the constant reservoir properties. Reservoir temperature increases with the relative permittivity and conductivity within a certain range of variation. The results show that reservoir properties, electromagnetic wave power and frequency have a significant impact on temperature distribution of the reservoir and perhaps are prime influencers. The mathematical model that takes into consideration the dynamic change of reservoir properties provides a theoretical basis for the field application of a high frequency electromagnetic heavy oil heating technology.