In this research, a new conceptual model for producing instantaneous unit hydrographs (IUHs) is introduced by a linear combination of the Nash model, which assumes that the discharge from a reservoir is a linear function of its storage, and a model called inter-connected linear reservoir model (ICLRM), which assumes that the discharge from a reservoir is a linear function of the difference of its storage and its adjacent downstream reservoir. By employing these assumptions, a system of first-order linear differential equations with three degrees of freedom (storage coefficient, number of reservoirs, and weighting coefficient) is obtained as the governing equation for the proposed model. This model may be considered as the general form of the two models and is therefore capable of simulating IUHs laying between these two models. To show the capabilities of the model, linear and curvilinear soil conservation service (SCS) hydrographs are simulated using dimensionless hydrographs obtained by this model. Moreover, several real hydrographs were simulated by the proposed model and compared with hydrographs obtained by Nash, ICLRM, and SCS models. The results show that the model yields more accurate results compared to other studied models and may be considered as a new model for simulating IUHs.

在这项研究中，通过纳什模型的线性组合引入了一种用于生成瞬时单位水位图（IUH）的新概念模型，该模型假定水库的流量是其存储量的线性函数，并且该模型称为互连模型线性储层模型（ICLRM），它假定储层的流量是其储层与其相邻下游储层之差的线性函数。通过采用这些假设，获得了具有三个自由度（存储系数，储层数量和加权系数）的一阶线性微分方程组，作为该模型的控制方程。该模型可以视为这两个模型的通用形式，因此能够模拟这两个模型之间的IUH。为了显示该模型的功能，使用通过该模型获得的无量纲水位图对线性和曲线土壤保持服务（SCS）水位图进行了模拟。此外，通过提出的模型对几个真实的水文图进行了模拟，并与通过Nash，ICLRM和SCS模型获得的水文图进行了比较。结果表明，与其他研究模型相比，该模型产生的结果更准确，可以被认为是模拟IUH的新模型。