Experimental Investigations of Pressure Losses on the Performance of a Micro Gas Turbine System

Test rig description and instrumentation

Flow path section between the compressor outlet and the airside recuperator inlet

Relative pressure loss between the compressor outlet and the recuperator inlet for 75%, 80%, and 90% turbine speed as a function of recuperator valve opening

Total compressor outlet pressure and total airside recuperator inlet pressure for 75%, 80%, and 90% turbine speed as a function of additional relative pressure loss Δp0

Electric power output for 75%, 80%, 87.5%, 90%, and maximum turbine speed as a function of additional relative pressure loss Δp0

Points of surge and new surge limit on compressor map

Operating points on compressor map for 75%, 80%, 87.5%, 90%, and maximum turbine speed as a function of pressure loss

Schematic diagram of the coefficients in the Hesse normal form for the surge limit linear fit

Relative distance Δdsurge to surge limit for 75%, 80%, 87.5%, and 90% turbine speed as a function of additional relative pressure loss

Ramp-up of recuperator valve from 52.5% to 100% at different gradients %/s as a function of time

Comparison of electric power output and the reciprocal pressure loss 1/Δpcr between the compressor outlet and the recuperator inlet as a function of time at valve opening settings from 52.5% to 100% (grad >80%/s at 75% turbine speed)

Controller instability issue of pressure loss increase at maximum turbine speed (grad 0.2%/s)

Relative distance Δdsurge to surge limit at 75% Ts as a function of bleed-air mass flow and turbine outlet temperature

Electric power output at 75% Ts as a function of bleed-air mass flow and turbine outlet temperature