The decisive factor of the " foamy oil phenomenon" in super-heavy foamy oil reservoirs is foam strength, which depends on foam existence time and foam volume. In order to quantitatively describe the major control factors on foam strength, a high-temperature-high-pressure (HTHP) visualized test model has been developed and used for the first time to test foam strength under conditions of different temperatures, dissolved gas/oil ratios (GOR) , pressure drop rates and pore sizes. Experimental results indicaternthat at high temperature, foam extinction rate is much higher than its formation rate; when dissolved GOR is lower than 5 m3/m3, the "foamy oil phenomenon" tends to disappear, the minimum pressure decline rate should not he less than 80 kPa/min to fully exert foamy oil effect; and experimental analysis of foam strength in porous media shows that the foam existence time in actual reservoir will be much longer than laboratory result.%超重泡沫油油藏中“泡沫油现象”的决定性因素在于产生泡沫的强度,而泡沫的强度取决于泡沫存在的时间和产生泡沫的体积.为定量描述泡沫强度的主控因素,自主研制了高温高压可视化泡沫强度测试模型,并利用该模型首次开展了不同温度、溶解气油比、降压速度及孔隙尺寸条件下的泡沫强度实验.实验结果表明,高温条件下泡沫破灭频率远大于生成频率;原始溶解气油比小于5 m3/m3,原油中“泡沫油现象”趋于消失;充分发挥泡沫油作用的最低降压速度应不小于80 kPa/min;多孔介质泡沫油实验趋势分析表明,实际油藏中泡沫存在的时间将远长于实验室内得到的结果.
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