ECS MATLAB

8/11/2019 ECS MATLAB

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ECS AND MATLAB


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WHAT IS AN ECS?

The environmental control system (ECS) of an aircraft provides airsupply, thermal control and cabin pressurization& humidity control forthe crew and passengers.

It modulates and controls the ventilation rates which are necessaryand essential for cabin safety and comfort

The ECS functions to provide ideal environmental conditions in the:

1. Cabins

2. Cockpit

3. Avionics compartment

4. Cargo compartment5. It also serves to detect smoke & suppress fires and thus assists to

prevent any calamity.


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REQUIREMENTS.

The ECS system must provide comfort conditions (i.e. some 24degree, 90-100 KPa, 50 -70% RH)

A sudden change in cabin pressure p>3 KPa (equivalent to z=300m nearsea level) can cause pain and vertigo

Human comfort demands relative humidity in the range 50-70%, but this isnot maintained aboard aircraft to avoid condensation problems on cold wallsand equipment, which tends to corrode metals and boost micro-organismgrowth. Hence Relative humidity is kept in the very low range, 10-20% RH.

The normal pressure conditions are pair>75 KPa and the Partial pressure ofoxygen pO2 >18.40 KPa

The ECS should also take into consideration structural constraints whichimpose limitation on the supply pressure.

Safety overpressure and underpressure needs to be limited for structural

reasons.


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AIR SOURCES

ENGINES APU

LOW PRESSURE GROUND CART (LPGC)


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THE AIR CONDITIONING PACK


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SYSTEM SCHEMATIC


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OPERATION


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TASK DESCRIPTION

The \Ground Cart Performance analysis requires the utilization of MATLAB performance

codes to evaluate the capacity of the Ground Cart to provide comfort conditions in cabin with given

predefined aircraft conditions.

Sr. No Cases Performance Criteria

1 Pull Down Evolution of Average cabin and mixer temperatures with time

2 Passenger Boarding Evolution of Average cabin and mixer temperatures with time

3 Steady state LPGC inlet Temperature needed to achieve a desired cabin temperature fordifferent mass flows.

4 Heating and cooling Time needed to reach 27C and 21C in the cabin for cooling and heating

respectively


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MODEL STRUCTURE

Cases

Lib

Model

Result

Run files

0.8

1.01.21.41.61.82.02.22.4

30 60 90 12 0 150 180 210 24 0FR

ESHAIRFLOW

FROMGC[kg/s]

TIME TO COOL CABIN TO 27 DEG ON GROUND[minutes]

GC Cooling Performance

OC1(ISA+30 /2 deg)OC2(ISA+30 /-10 deg)OC3(ISA+30 /-20 deg)OC4(ISA+23 /2 deg)


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LOOP FILEFunctions

Initialize CASE_TYPE

CASE NOS

Initiates loop sequence

Initialize model type

Output result file

MATLAB

WORKSPACE

VARIABLES

CASE FILES

CASE_TYPE

PT

PB

OC

OS

OHLIB FILES

LIB functions

RESULT FILE.mat & .xls files

MODEL AS A WHOLE


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THANKYOU

Documents

ECS MATLAB