5. Combustion gases with k=1.35, Cp=1107 J/(kg.K) and R= 287 J/(kg.K) flow at stagnation pressure and stagnation temperature of 390kPa and 1150 K respectively, flow through a 90° IFR turbine to an exit static pressure of 100 kPa. The total to static efficiency is 80% and the flow leaves the stator choked (Mach Number=1). The relative velocity at the inlet to the rotor is radial and the flow leaves the turbine without a swirl. Find (a) the work delivered per unit flow rate, (b) the impeller tip velocity and (c) the flow angle at the inlet to the rotor. :-

There are two turbine stages with a reheater in between, as shown below and the following conditions are provided. Assume the mass flow rate of air = 1 Kg/s. Turbine stage 1 Stream 1 2 3 4 Reheat combustor P (kPa) T (K) 1200 350 350 100 1200 1200 3 Turbine stage 2 h (kJ/kg) W cycle • Determine the total work developed, which is the sum of the work developed by the first stage and the work developed in the second stage. • Determine the heat added in the reheater. • If the reheat is turned off, streams 2 and 3 no longer exist and we go directly from 1 to a new state at stream 4. What is h4 and what is the work generated in the turbine in this case?

a turbojet on a test stand air at inlet has density of 1.1 kg/m^3 at the exit gas has higher velocity and higher temp, but pressure is the same. inlet area is 0.5m^2 and free stream velocty is 200m/s. fuel air mix is 1:15 at exit, engine area is 0.3m^2, gas velocity 800m/s Determine the density of gas at exit and evaluate reaction forces to hold test stand Turbojet Engine V1 V2 P2 A1 A2 Test Stand

(b) Derive an expression for thermal efficiency of ideal Brayton cycle