## 6 Summary and Conclusions  
The technologies employed in microfluidic devices have become much more sophisticated and complex over the past decade because of the significant developments of these devices in understanding the phenomena in human body cells. The pace of these improvements in microfluidic devices has accelerated over the past few years. Experimental methods to optimize these devices and understand related phenomena have lost their popularity because of the high costs associated with them and challenges on the way and numerical simulation methods have become the subject of interest to understand cellular-related phenomena better to help to optimize these devices. These methods, however, suffer from high computational costs. Thus, researchers have devoted their efforts to improve these methods, and new modifications have been introduced to help alleviate this problem and make them more applicable to study real-world problems. The current paper gave a comprehensive and up-to-date review of various numerical methods available to study the cellular flow problems, with the primary focus on three highly used methods in body cells simulation: CFD, LBM, and DPD, but other particle-based methods and summarized and compared with these three methods as well. Also, schematics of algorithms were presented to \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Tools** & **Multiple Algorithms** & **Tools** & **Multiple Algorithms** \\ \hline Abalone & Yes & COSMOS & Yes \\ ACEMD & Yes & CP2K & Yes \\ ADF & Yes & Culgi & Yes \\ Ascalaph Designer & Yes & Desmond & Yes \\ CHARMM & Yes & Discovery Studio & Yes \\ ChemDoodle 3D & No & GROMACS & Yes \\ GROMOS & Yes & HyperChem & Yes \\ LAMMPS & Yes & MAPS & Yes \\ SAMSON & No & Scigress & No \\ MDynaMix & No & Q & No \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Software packages developed based on MD or DSMC and associated methods. Figure 10: A few applications of moving-particle semi-implicit (MPS) and smoothed particle hydrodynamics (SPH) methods in simulation of RBCs. (**a**) SPH particle discretization of a single normal shaped RBC [112]. (**b**) Snapshot of flexible RBCs suspension in in blood flow using MPS method. [119]. be a guideline and starting point of understanding the procedure of implementing each technique for researchers. Also, this review discusses the practice areas for each method to be used depending on the characteristics of the problem being investigated and strengths of each method. The methods discussed in this work are summarized in Table 3 along with a short description of their applications and their associated dimensional nature. To emphasize the importance of each method for applicable problems, a summary comparison is provided in the following to conclude the benefits and drawbacks of each technique presented in this work. * CFD methods have proven to be applicable to investigate the phenomena related to human arteries. However, to their more significant scale nature, they cannot be implemented to study smaller-scale problems related to body cells. * Many commercial software packages are available to study problems with high accuracy. * LBM is of highly parallel nature and can easily be implemented in massively parallel computing systems because of its local dynamics. LBM also offers excellent capabilities to be combined with other methods such as IBM to model RBC-flow interactions and deformation of RBCs. This is entirely different from modeling of the RBC membrane in physically connected particles like in SPH and DPD methods. * LBM and DPD, offer capabilities to model thermal fluctuation in the simulations, which is necessary to study phenomena such as RBCs aggregation. * LBM and DPD, as mesoscopic methods, can be used to study cellular flow problems with reasonable computational costs compared to microscale models. * SPH, unlike LBM and DPD, does not take into account the thermal fluctuations because of the lack of a fluctuation-dissipation function in its nature.