## 1 Introduction  
We enhanced the thermal conductivity of the coolant based on its essential effects on many engineering applications, such as the heat treatment of metals [1]. The aim of the cooling process is to improve the metals' mechanical properties, such as ductility and strength. Creating more useful metals is one of the most important aims of researchers. In this process, the metal is heated to a certain temperature and then cooled in a series of specific operations. Nanofluids have properties that make them useful in many heat transfer applications, such as microelectronics, fuel cells, pharmaceutical processes, hybrid powered engines, engine cooling/vehicle thermal management, domestic refrigerators, heat exchangers, and the reduction of flue gas temperature in boilers [2]. Compared to the base fluid, thermal conductivity and the convective heat transfer coefficient were enhanced. In 1995, the authors of [3] proposed the idea of enhancing the thermal conductivity of the fluids using these nanoparticles. This was the first push for researchers to conduct studies that investigated the effects of nanoparticle types, sizes, and concentrations on the heat transfer characteristics and took into consideration some of the effects such as the thermal radiation, variable heat flux, magnetic field, and suction/injection processes [4]. We studied the magnetohydrodynamics (MHD) free convection of Al\({}_{2}\)o\({}_{3}\)-water nanofluid by considering the thermal radiation problem [5]. This study examined the flow and heat transfer over an unsteady shrinking sheet with suction in nanofluids [6]. The natural convection flow of a nanofluid over a linear stretching sheet, in the presence of a magnetic field, was discussed [7]. The mixed convection boundary layer flow from a horizontal circular cylinder was embedded in a porous medium, which was filled with a nanofluid [8]. We observed the boundary layer flow over a stretching/shrinking surface under an external uniform shear flow with a convective surface boundary condition in a nanofluid [9]. The effect of a magnetic field on the flow and heat transfer of a nanofluid over an unsteady continuous moving surface--and in the presence of suction/injection--was observed [10]. [PERSON]'s model was used to study the heat and mass transfer flow in a thin nanofluid film over an unsteady stretching sheet [11]. The study focused on the effects of thermophoresis and Brownian motion on the boundary layer flow of a nanofluid in the presence of thermal stratification--due to solar energy [12]. The flow and heat elements are transferred, in a nanofluid, over a moving surface with a non-linear velocity and variable thickness and in the presence of thermal radiation [13]. The boundary layer flow was maneuvered over a moving surface, which was embedded into a nanofluid, in the presence of a magnetic field and suction/injection [14]. We analyzed the effects of thermal radiation and heat generation on the mechanical properties of an unsteady, continuously moving cylinder in a nanofluid in the presence of suction/injection [15]. The flow and heat transfer was observed over a moving surface in a nanofluid with a non-linear velocity and variable thickness and in the presence of Brownian motion. Micropolar fluids may represent fluids that consist of rigid, randomly oriented (or spherical) particles that are suspended in a viscous medium, where the deformation of fluid particles is ignored. The microrotation of the suspended microparticles within the fluid is discussed through the theory of micropolar fluids. In this theory, the fluids can be subjected to the surface and body couples, in which the material points in the volume elements can both move around the centers of mass and deform. Many researchers, such as the authors of [16], have investigated the micropolar fluid theory by studying the behavior of the unsteady boundary layer flow of a micropolar fluid near the rear stagnation point of a plane surface [17].