Indirect inverse flux mapping of a concentrated solar source using infrared imaging

Abstract

With the growing interest in high-flux solar sources, a need exists for simple, accurate, and inexpensive strategies to characterize their output radiative flux. In this paper, the irradiation output from a 10 kWe xenon lamp solar simulator is characterized by an inverse mapping technique that uses a custom radiometer and infrared camera, validated by a direct characterization method (heat flux gauge). The heat flux distribution is determined in a vacuum chamber using an easily obtainable graphite target and an inverse heat transfer model. The solar simulator produces peak fluxes in the range of 1.5–4.5 MW/m2 as measured directly by a heat flux gauge, and its output can be controlled using a variable power supply. Spectral measurements indicate that minor variations in the simulator’s output with respect to its current supply occur in the spectral range of 450–800 nm. The radiometer presented in this work allows for characterizing solar irradiation under practical conditions (e.g., inside a solar reactor) and thus accounts for deviations due to additional components, such as viewport effects. Additionally, it provides an inexpensive and efficient means of monitoring any deterioration in the performance of solar sources over time without the need for complex recalibration.

Graphitic surface layer formation on organic substrates for electronics using a concentrated solar simulator

“…These parameters include the duration and number of flashes, pressure level (P), and gas composition/flow rate (when applicable), where the duration between each flash was maintained constant at 25 s. Importantly, the flash mode's heat flux distribution varies linearly from its steady-state distribution, where the flux values start at approximately 70% of their steady-state values represented by Eq. 1 [17,22]. Therefore, the peak heat flux for this study is estimated to be 3.2 MW/m 2 .…”

“…The output irradiance at the focal plane of a single-lamp concentrated light source strongly resembles a Lorentzian distribution [17]. This heat flux distribution has been directly measured at discrete points in prior work [22] outside the vacuum chamber and at the focal plane using a heat flux gauge. Heat flux measurements were also complemented and verified with numerical simulations using a validated Monte Carlo ray tracing in-house code [23].…”

High-Quality AB Bilayer Graphene Films by Direct Solar-Thermal Chemical Vapor Deposition

“…The HFSS includes a 10 kW e short xenon arc lamp (Superior Quartz, SQP-SX100003) placed at the focal point of a silver-coated ellipsoidal reflector (Optiforms, E1023F). The reflector collects the emitted radiation of the lamp placed at its focal plane and concentrates the rays, and the heat flux at the target plane was characterized in prior work with a Gaussian–Lorentzian distribution as q ″ ( r , I ) = A ( I ) [ 1 − α σ g 2 π e − r 2 / 2 σ g 2 + α π true( σ normall r 2 + σ normall 2 true) ] where the fitted coefficients are defined as follows: A ( I ) = (0.740 × I – 20.5) kW/m is the amplitude parameter adjusting both profiles as a function of HFSS current ( I ), σ g = 0.00829 m and σ l = 0.0492 m are the Gaussian and Lorentzian distribution parameters, respectively, α = 0.519 is a weighing parameter, and r is the radial distance from the center. The output heat flux can be varied and controlled by adjusting the current ( I ) (100–200 A) from a DC power supply.…”

“…The HFSS includes a 10 kW e short xenon arc lamp (Superior Quartz, SQP-SX100003) placed at the focal point of a silver-coated ellipsoidal reflector (Optiforms, E1023F). The reflector collects the emitted radiation of the lamp placed at its focal plane and concentrates the rays, and the heat flux at the target plane was characterized in prior work 47 with a Gaussian−Lorentzian distribution as…”

Continuous Solar-Thermal Methane Pyrolysis by Roll-to-Roll Processing

“…The irradiation output from the solar simulator onto the fibrous roll has been characterized using an inverse heat flux mapping method [29], giving a radially-symmetric heat flux distribution (𝑞𝑞 s ,, ) that follows a pseudo-Voigt function:…”