EXTERNAL FLOW

Bypass flow between pod and tube should not get chocked for a given Mach no of pod

Based on isentropic relations the bypass area through which the flow passes through is calculated

Area of bypass=1.3885m^2

By setting values for all parameters that satisfy the area constraints and then calculate the required Abypass and Adiffused.The differences between the actual and required values are plotted and the value for which required conditions is satisfied for both diffuser and bypass area are obtained.

MATLAB OPTIMIZATION RESULTS

DIFFUSER

At top speeds of pod close to Mach no of 0.8 the air needs to be slowed down to atleast Mach no of 0.6 before the compressor takes it in so that it performs efficiently.

The air that exits the diffuser is split into two flows.Some mass flows into the compressor.Other portion is bypassed through the pod without compressing.This flow can be used to cool the air that goes through the compressor.

Dimensions

Diffuser inlet area-0.51m^2

Diffuser Exit Area-0.7922m^2

COMPRESSOR

To force the air through the pod in a smaller area leaving space for passenger cabin.

Compressor allows a greater pod/tube ratio.

Based on isentropic calculations

Compressor Power- 10kW

PROCESS DIAGRAM

Air in-P=100 paT1=292Km=0.167kg/s

Air out-P=119.51PaT2=307.25K

m2=0.0835

m1=0.0835

W=10kWP3=343.56PaT3=415.46K

T4=300K

T5=210.85KP5=100Pa

T6=422.71K

Diffuser

Axial Compressor

Nozzle Expander

Heat Exchanger

NOZZLE EXPANDER

Isentropic Calculations-

Nozzle exit Velocity-472.79m/s

Nozzle exit Mach Number-1.62

Thrust-12.5N

A De Laval nozzle can be used to achieve these conditions