Double Deck Elevator Analysis

Double Deck Elevator Basic Analysis
“Journey of a thousand mile starts with a step” and the step in elevator analysis is starting with very tough specifications related to the building, speed, passengers’ behavior, etc. These specifications are the same for single deck elevator analysis which are presented in [7]. However, the double deck elevator has more specifications due to its nature.
This chapter includes the assumptions that the derivations are based on, Monte Carlo simulation, derivation of RTT components (expected number of stops, highest reversal twin floors and passenger transfer efficiency coefficient), derivation of coincidental stopping coefficient, solution for buildings with odd number of occupant floors and finally numerical

In this chapter assumption 8 and 13 can be disregarded for equations with unequal floor populations. Also, assumptions 2, 7 8, 9 and 13 can be disregarded when deriving equations in chapter 6.
Round Trip Time Components
The round trip time is the time the elevator spent in picking up passengers from their origins and delivering them to their destinations then returning to its starting floor. For incoming traffic, it is the time the elevator spends picking up passengers from the main entrance and delivering them to their destinations then returning back to the main entrance.
The round trip time includes three parts: boarding and alighting passengers’ time, stopping time and the time the elevator spends returning to the main entrance. The three parts are discussed in the three following sub-sections. Then all parameters affect each part are discussed in the next sections in this chapter.
Before starting the derivation, it is worth nothing to note that the probable journeys might be between twin floors only and each twin means two adjacent floors (i.e. the odd floor and the even floor above

This coefficient represents the efficiency of passengers alighting, since it is not necessarily for odd and even passengers that alight at the same twin to be equal.
Total alighting time equals the time needed for one passenger to alight multiplied by the number of passengers and passenger transfer efficiency coefficient. The equation below represents passengers alighting time: t_out=t_po*P*PTEC …… (5.2.2)
Stopping Time
To make transferring passengers possible, the elevator must stop so they can board and alight to/from the elevator. For each stop the elevator must slow down its speed (i.e. decelerate) then open its door and passengers board or alight to/from the elevator then close its door and then accelerate to reach its rated speed.
Acceleration and deceleration time depends on the equation of travelling one twin floors under rated speed which depends on the twin floors height and the speed, the acceleration and the jerk of the motor.
The time the elevator spends to travel one twin under rated speed with acceleration and deceleration: t_(travelling one twin floors under rated speed with acc. and dec.)=d_T/v+v/a+a/j ……