The multiwell horizontal pad is an effective method to enhance oil recovery for unconventional reservoirs. Microseismic evidence indicates that the stimulated reservoir volume (SRV) may have originated in the overlap region created by multi-well fracturing. However, the majority of SRV modeling studies have concentrated on a single well, ignoring the interference from offsetting wells. In this study, a novel model for modeling the SRV and multiwell horizontal pad in unconventional reservoirs is developed using an effective semi-analytical method. The proposed semi-analytical model is capable of simulating the behaviors of a multiwell horizontal pad with an irregularly shaped SRV and an impermeable boundary. The transient pressure behaviors of the multiwell horizontal pad with SRV are significantly different than that of a single isolated well, as demonstrated by the results. The linear flow between wells, the pseudoradial flow (PRF) of the multiwell pad in SRV, the transitional flow, and the final pseudoradial flow (PRF) of the multiwell pad all correspond to an extremely unusual transient pressure response. Due to the high flow capability of SRV, pressure diffusion occurs at a faster rate, resulting in the appearance of these flow regions in advance. Sensitivity analysis confirms that as the scale of SRV increases, the duration of the flow influenced by the SRV increases. The SRV and compensating wells result in a negligible PRF, while the pressure behaviors exhibit a gradual rise. This phenomenon may serve as a demonstration of the extremely rare occurrence of radial flow or PRF in unconventional reservoirs. The horizontal line value for the PRF in SRV is proportional to the total production of the well pad. The horizontal line value for the final PRF is also related to the unstimulated region's mobility ratio, the well pad's production rate and 0.5. The case in Junggar Basin shows that the natural fracture permeability in the SRV is 2.5 mD, the matrix permeability is 0.044 mD, the rectangular SRV side lengths are 1600 m and 880 m, the mobility ratio and dispersion ratio are 15, and the wellbore storage coefficient is 0.5 m³/MPa.

多井水平垫层是提高非常规油藏采收率的有效方法。微震证据表明，增产储层体积（SRV）可能起源于多井压裂造成的重叠区域。然而，大多数 SRV 建模研究都集中在单井上，忽略了补偿井的干扰。在这项研究中，使用有效的半解析方法开发了一种用于模拟非常规油藏中的 SRV 和多井水平垫层的新模型。所提出的半解析模型能够模拟具有不规则形状的 SRV 和不渗透边界的多井水平井的行为。带 SRV 的多井水平平台的瞬态压力行为与单井隔离井的瞬态压力行为显着不同，如结果所示。井间的线性流动、SRV 中多井平台的伪径向流（PRF）、过渡流和多井平台的最终伪径向流（PRF）都对应于极不寻常的瞬态压力响应。由于 SRV 的高流动能力，压力扩散以更快的速度发生，导致这些流动区域提前出现。敏感性分析证实，随着 SRV 规模的增加，受 SRV 影响的流动持续时间增加。SRV 和补偿井导致的 PRF 可以忽略不计，而压力行为表现出逐渐上升的趋势。这种现象可以作为非常规油藏中极少发生径向流或PRF的证明。SRV 中 PRF 的水平线值与井场的总产量成正比。最终PRF的水平线值也与未增产区的流度比、井台的产率和0.5有关。准噶尔盆地案例表明，SRV 天然裂缝渗透率为 2.5 mD，基质渗透率为 0.044 mD，矩形 SRV 边长分别为 1600 m 和 880 m，流度比和弥散比为 15，井筒储量系数为 0.5 m³ /兆帕。