2023

TBPS 5

Complex Cycles

Monash University

Mech. & Aerosp. Eng.

(a) What is your choice for the condenser operating pressure?

(b) What is your choice for the maximum operating temperature

(c) What is your choice for the operating pressure in the collector tubing in the

solar panels?

(d) What is your design choice for the temperature of the hot stream exiting the

recuperator (regenerator)?

(e) Sketch the T-s diagram for your design. Showing all the required information

on the diagram.

(f) What is the area of the solar collector required?

(g) What is the condenser load in kW?

(h) What is the net power generated by your design? (A 4-person household in

Melbourne requires 1 kW power, on average.)

(i) What is the power output of the expander turbine in kW?

(i) What is the pump power consumption in kW?/nQuestion 4

Organic Rankine Cycles (ORCs :) use refrigerants as the working fluid to generate

electric power at lower temperatures and pressures than steam-based power gener-

ation. These are increasingly beginning to be used for designing micro-scale solar-

power electric generators to power single households or small communities. They

tend to be financially competitive when compared with photovoltaic solar applica-

tions because of the lower cost: they do not require high-end photovoltaic materials.

Perform a first pass at designing a household solar-driven micro-ORC system shown

in the figure below

Solar dation

2777777

Scroll

expander

Solar panels

3. Circulation rate: 0.045 kg/s

4. Maximum permitted temperature: 130 °C

5. Average solar irradiation: 750 W/m²

Coolant in

Coolant out

You are the following specifications.

1. Working fluid: R-134a

2. Condenser cooled by either ambient air or by cold water, at a temperature of

25 °C.