Session: 06-02: CSP Receivers and Reactors I

Paper Number: 169973

169973 - High Fidelity Modeling of a Commercial Scale Falling Particle Receiver 

Abstract: 

Generation 3 concentrating solar power systems which use particles as the heat transfer and storage media have the potential to reduce the levelized cost of electricity when compared to Generation 2 molten salt based systems. A falling particle receiver can be used to convert the concentrated solar flux to heat by directly irradiating a curtain of particles within a receiver cavity. The flux profile of the concentrated radiation is unevenly distributed on the particle curtain with higher flux at the center of the curtain and lower flux at the edges. The high flux at the curtain’s center can cause backwall overheating and increased thermal losses due to asymmetric particle heating. To mitigate this effect, modular curtain generating valves can vary the particle mass flow rate along the width of the receiver. This creates a more opaque curtain at the highest flux portion of the receiver to more efficiently absorb the solar irradiance.

 A commercial scale falling particle receiver computational fluid dynamics model was created and run on the high performance compute clusters at Sandia National Labs to assess the efficacy of the variable mass flow rate design. A nominal and off design flux condition were considered representing conditions for morning and mid day for both a uniform and varied mass flow rate curtain.

The mid day scenario, representing the design point conditions for the receiver, featured a relatively small difference in receiver efficiency between the uniform and varied cases, <1%, while the off design condition yielded a significantly higher efficiency for the varied mass flow case, ~2%.

Presenting Author: Nathan Schroeder Sandia National Laboratories

Presenting Author Biography: Nathan Schroeder is a mechanical engineer and senior member of the technical staff at Sandia National Labs. His research focuses on generation 3 particle based concentrating solar power systems and industrial decarbonization.