b'Engineer Innovation | Aerospace[null] [ft]x103 x10320 35Cockpit - heat flow rate [W] (Z1_insul_thick=1 in, Z2_insul_thick=1 in, )Cockpit - heat flow rate [W] (Z1_insul_thick=3 in, Z2_insul_thick=2 in, )Cabin 1st Floor - heat flow rate [W] (Z1_insul_thick=1 in, Z2_insul_thick=1 in, ) 30Cabin 1st Floor - heat flow rate [W] (Z1_insul_thick=3 in, Z2_insul_thick=3 in, )15 Aero_Mision - Aircraft Altidue [ft]2520101510550 0-4 -3 -2 -1 0 1 2 3 4 5 x103X: Time [s]PHX the Simcenter Amesim thermal library.of a 4-wheel ACM is depicted in the The equivalent thermal circuit of afigure above. section of a double deck fuselage 4-wheelsaircraft is illustrated in the pictureWith this kind of model it is possible to bootstrap below on the left. On the right, thestudy the gas temperature and corresponding Simcenter Amesimpressure evolution in the ACM MHX model is depicted. components and size them effectively. Furthermore, the start-up procedure Condenser This nodal approach can be applied towas simulated as follows. The aircraft the entire fuselage discretizing it alongis at rest on the ground. At t = 2s, the Reheater the longitudinal axis. flow control valve connecting the left Fan engine bleed system to the ACM is Using this approach, the desired cabinopened, letting hot pressurized air flow temperature is imposed, while thethrough it. The right flow control valve atmospheric boundary conditions,is opened at t = 3s. The mixing point computed with the dedicatedtarget temperature is set at 293 K, and components of the Simcenter Amesimthen lowered at 288 K and 283 K at 12 Aeronautics and Space library, varyand at 15 s respectively.according to the specified mission profile. As a result, you can computeThe results are plotted below. In the the heat flow rates in the cabin duringfirst subplot one can notice that as the the flight mission. These are plottedflow control valve is opened, the below for different thicknesses of thepressure builds up accelerating the insulation layer. The heat flow ratesturbine. In the second subplot, the represent the required power that thetarget and computed temperature of ECS must deliver to maintain thethe mixing point are plotted, together desired cabin temperature throughoutwith the trim air valve opening the flight. fraction.Modeling air cycle machinesAnalyzing resultsOnce the preliminary powerFrom a performance modeling requirements for the ACM areperspective, the rest of the ECS mainly available, these can be modeled usingconsists of pipes and other equipment the Simcenter Amesim Gas Mixturededicated to the distribution of the and Moist Air library. This is the secondpressurized air from the engine bleed step of the methodology. An exampleports to the cabin. This portion of the 48'