Discrete vs. Continuous Simulation: When Does It Matter?

摘要

The purpose of this study is to illustrate the similarities and differences between discrete event simulation and continuous simulation modeling. A simple M/M/2 queuing system with crowd-dependent arrival rate is used. In the first part, the arrival rate decreases immediately as the number of customers in the system increases. The system is modeled using discrete event and continuous simulation. The results of two simulations are compared with each other and with their analytical solutions. In the second part, the number of customers in the system affects the arrival rate first with a continuous information delay, then with a discrete delay. Discrete and continuous simulations give very similar results in terms of dynamic behaviors of system variables. There are some minor differences in terms of the steady-state values of the variables, particularly the average time spent in system. Finally, increasing proportionately all parameters of the system (arrival rate and number of servers), reduces the discreteness of the system, bringing the discrete and continuous simulation results much closer.