本文指出，在研究细颗粒浑水的流动变形及群体沉降等基本特性时，对于微小浓度的浑水，应考虑包围颗粒的结合水薄膜体积的影响；对于高浓度浑水，应进一步考虑颗粒碰撞接触形成孔隙的髟响。根据上述观点，导得高浓度浑水粘滞性公式、非絮凝群体沉速公式及极大浓度公式。文中还得到高浓度粗颊粒浑水群体沉速经验公式。应用各方面试验资料验证各种公式，获得较好的结果。

Unsteady Water quality model with multiparameter for the river network has been studied in this paper. The model reflects the characteristics of the unsteady flow with different direction and that of the unsteady water quality under aerobic, anoxic and anaerobic conditions. The model includes the various equations for DO, COD, BOD5, NBOD, NH4+-N.All parameters in the model have been obtained by the research for the observation on the field and the experiment in the laboratory. An equation of longitudinal dispersion coefficient has also been developed. Appling the computing method of dynamic coupling, the model has been verified by the data observed on field. The model has been applied to the program for controlling water quantity and water quality in order to improve the water quality of the river network of Wuxi city in China.

The thixotropy properties and the motion law of a sphere in the Bingham fluid have studied. Through observation of the setting motion of a single sphere in the Bingham fluid on the X-ray screen, it has been discovered that the mud in estuaries and along sea bay, and the hyperconcentrated flow all behave as the Bingham fluid with thixotropy properties as the large sediment concentration. Through derivation, the theoretical relationship between the yield stress and non-setting maximum sphere supported by the stress for the Bingham fluid has been developed, the equations for calculating the increasing yield stress and the non-setting maximum sphere diameter with the duration at rest of the slurry have been obstained. In consideration of the effect thixotropy on the fluid motion. The Navier-Stokes equation group for the Bingham thixotropy fluid has been developed. Through future study of the flow boundary condition of setting motion of a single sphere in the Bingham thixotropy fluid. And the solving of the Navier-Stokes equation group under the small Reynolds number. The theorecital equation of the drag force of the Bingham thixotropy fluid flowing around a sphere has been deduced. The theorecital relationship between drag coefficient and Revnolds number has been derived. By use of the experimental data of rheological test of various slurries measured with viscometer and those of single sohere motion observed on the X-ray screen, the above equation have been verified. The equations are in good agreement with the experimental data for various slurries.

对H.A.爱因斯坦等国内外数10种不同形式和结构的泥沙启动条件进行分析研究，统一转化为无因此起动切力 θc=γc/(νc-ν)d 的形式，并分析计算出无粘性均匀沙的 θc 值。一般来讲， 是界于0.0231～0.0716之间的一个常数值。从分析结果可看出各种公式之间的差别，为使用选择公式提供了科学的依据。

本文针对平原河网地区，河道纵横交错、水流流向顺逆不定、水流中输送的物质浓度属非稳态非均匀变化等特点，推导得到了使用与各种流动情况下，求解河网对对流输移问题隐式差分方程的一套计算公式，及相应的河网计算方法。运用这一方法进行述职求解，不仅能反映上述各种特点，还具有所需的计算机内存少，计算速度快，易于掌握点击应用方便等优点。