Shadows of the Kerr–Newman-dS black hole surrounded by quintessence and a cloud of strings are investigated. For a spherically symmetric nonrotating black hole, its shadow is circular and its size is independent of an observation angle and a plane on which a circular photon orbit exists. The shadow sizes are significantly influenced by the parameters involving the cloud of strings, quintessence parameter, magnitude of quintessential state parameter, and cosmological constant. The black hole shadows increase with the cloud of strings and negative quintessential state parameter increasing or the quintessence parameter and cosmological constant decreasing. When the black hole is spinning and axially symmetric, the black hole shadow is dependent on the observation angle and the black hole spin. The effects of the parameters excluding the spin parameter and the observation angle on the sizes of black hole shadows in the rotating case are similar to those in the nonrotating case. The black hole shadows decrease as the black hole spins increase. When the observation angle in the range of 0 and \(\pi /2\) is large, the black hole shadow is deformed like the D shape for a high spin, but is close to a circle for a low spin. When the observation angle is small, the black hole shadow seems to be a circle regardless of the high or low spin case. Based on the Event Horizon Telescope observations of M87*, the constraint of the curvature radius is used to constrain these parameters. For slowly rotating black holes, the allowed regions of the parameters including the cosmological constant are given.

研究了被精华和弦云包围的克尔-纽曼-dS 黑洞的阴影。对于球对称非旋转黑洞，其阴影是圆形的，其大小与观察角度和圆形光子轨道所在的平面无关。阴影大小受弦云、本质参数、本质状态参数大小和宇宙常数等参数的显着影响。黑洞阴影随着弦云和负本质态参数的增大或本质参数和宇宙常数的减小而增大。当黑洞旋转且轴对称时，黑洞阴影取决于观测角度和黑洞旋转。旋转情况下除自旋参数和观测角度外的参数对黑洞阴影大小的影响与非旋转情况类似。黑洞阴影随着黑洞自转的增加而减少。当观测角度在0到\(\pi /2\)范围内较大时，对于高自旋黑洞阴影变形为D形，而对于低自旋黑洞阴影则接近于圆形。当观察角度较小时，无论高自旋还是低自旋情况，黑洞阴影似乎都是圆形。基于事件视界望远镜对M87*的观测，采用曲率半径的约束来约束这些参数。对于缓慢旋转的黑洞，给出了包括宇宙学常数在内的参数的允许区域。