Thermal Engineering

Solar Thermal Simulator

Simulate flat-plate solar collector behavior. Explore the relationship between solar irradiance, fluid flow parameters, and system heat loss to compute thermal efficiency and temperature gain.

Model

Hottel-Whillier-Bliss

Steady state

Fluid Preset

Water

Cp = 4180 J/kgK

Output

CSV

Export ready

Parameters

Working Fluid

Solar Irradiance800 W/m²

1001200

Ambient Temp (Ta)25 °C

-2050

Inlet Fluid Temp (Ti)40 °C

10100

Collector Area (Ac)2.00 m²

Mass Flow Rate0.02 kg/s

0.0050.1

Optical Efficiency (τα)0.85

0.50.95

Heat Loss Coeff (UL)4.00 W/m²K

110

Animated solar cycle sweep

Thermal Model

Heat Removal Factor (FR)

FR = (m_dot * Cp / (Ac * UL)) * (1 - e^(-Ac * UL * F' / (m_dot * Cp)))

Useful Heat Gain (Qu)

Qu = Ac * FR * [G * τα - UL * (Ti - Ta)]

Efficiency (η)

η = Qu / (Ac * G)

Fluid density and thermal capacitance determine dynamic temperature response.

Maximum possible collector efficiency occurs when thermal losses are minimized (Ti ≈ Ta).

Linked System Diagram

Useful Heat Gain

1069.3W

Thermal Efficiency

66.8%

Outlet Temperature

52.8°C

Heat Removal (FR)

0.862

Heat & Efficiency Curves

Collector Performance Data

Solar Irradiance (W/m²)	Useful Heat (W)	Efficiency (%)
100 W/m²	43.1	21.6%
200 W/m²	189.7	47.4%
300 W/m²	336.3	56.1%
400 W/m²	482.9	60.4%
500 W/m²	629.5	63.0%
600 W/m²	776.1	64.7%
700 W/m²	922.7	65.9%
800 W/m²	1069.3	66.8%
900 W/m²	1215.9	67.5%
1000 W/m²	1362.5	68.1%
1100 W/m²	1509.1	68.6%
1200 W/m²	1655.7	69.0%