Modified approach to capillary hysteresis based on a similarity hypothesis

We present herein a simplified approach to the capillary hysteresis phenomenon. This approach is based on a similarity hypothesis resembling that of Philip (1964), but different basic assumptions lead to a quite simple and handy method of predicting the relationships between the capillary head and the water content within the hysteretic loop. Only the boundary curves of the main loop are required in order to derive analytically the scanning curves. The reliability of the proposed modified model is demonstrated by a comparison of the predicted scanning curves with the measured ones. The computed results are often in more satisfactory agreement with experiments than those obtained with the use of the general Néel‐Everett model.