scholarly journals Particle Flow Testing of a Multistage Falling Particle Receiver Concept: Staggered Angle Iron Receiver (STAIR)

2020 ◽  
Author(s):  
Lindsey Yue ◽  
Nathan Schroeder ◽  
Clifford K. Ho
Keyword(s):  
Power Systems ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Particle Mass ◽  
Particle Flow ◽  
Test Apparatus ◽  
Angle Iron ◽  
Flow Test ◽  
Free Falling

Abstract Falling particle receivers are an emerging technology for use in concentrating solar power systems. In this work, a staggered angle iron receiver concept is investigated, with the goals of increasing particle curtain stability and opacity in a receiver. The concept consists of angle iron-shaped troughs placed in line with a falling particle curtain in order to collect particles and rerelease them, decreasing the downward velocity of the particles and the curtain spread. A particle flow test apparatus has been fabricated. The effect of staggered angle iron trough geometry, orientation, and position on the opacity and uniformity of a falling particle curtain for different particle linear mass flow rates is investigated using the particle flow test apparatus. For the baseline free falling curtain and for different trough configurations, particle curtain transmissivity is measured, and profile images of the particle curtain are taken. Particle mass flow rate and trough position affect curtain transmissivity more than trough orientation and geometry. Optimal trough position for a given particle mass flow rate can result in improved curtain stability and decreased transmissivity. The case with a slot depth of 1/4″, hybrid trough geometry at 36″ below the slot resulted in the largest improvement over the baseline curtain: 0.40 transmissivity for the baseline and 0.14 transmissivity with the trough. However, some trough configurations have a detrimental effect on curtain stability and result in increased curtain transmissivity and/or substantial particle bouncing.

scholarly journals Characterization of Particle Flow in a Free-Falling Solar Particle Receiver

2015 ◽  
Author(s):  
Clifford K. Ho ◽  
Joshua M. Christian ◽  
David Romano ◽  
Julius Yellowhair ◽  
Nathan Siegel
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Numerical Models ◽  
Particle Flow ◽  
Concentrating Solar Power ◽  
Power Cycles ◽  
Solar Particle ◽  
Free Falling

Falling particle receivers are being evaluated as an alternative to conventional fluid-based solar receivers to enable higher temperatures and higher efficiency power cycles with direct storage for concentrating solar power applications. This paper presents studies of the particle mass flow rate, velocity, particle-curtain opacity and density, and other characteristics of free-falling ceramic particles as a function of different discharge slot apertures. The methods to characterize the particle flow are described, and results are compared to theoretical and numerical models for unheated conditions.

The Investigation of Back-Mixing Particles near Dust Outlet in Cyclone Separator with Tangential Inlet

2011 ◽  
Vol 239-242 ◽  
pp. 2142-2148
Author(s):  
Hui Min Tan ◽  
Jian Jun Wang ◽  
You Hai Jin
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Particle Diameter ◽  
Particle Mass ◽  
Cyclone Separator ◽  
Axial Distribution ◽  
Computational Fluid Dynamics Analysis ◽  
Back Mixing ◽  
Tangential Inlet

Based on experimental and computational fluid dynamics analysis, the phenomenon of particle back-mixing near the dust outlet in cyclone separator with tangential inlet was studied. The results show that particle back-mixing appears near the dust outlet geometry. Particle back-mixing can be divided into dust hopper back-mixing and discharge cone back-mixing for different generation mechanism. The upward flow coming from dust hopper, which occupies 17.7% of the inlet gas, can induce dust hopper back-mixing. The particle mass flow rate that caused by dust hopper back-mixing occupies 46.6% of total inlet particle mass flow rate. Precessing vortex core, bias flow and high turbulent intensity near the dust outlet can induce discharge cone back-mixing. For both dust hopper back-mixing and discharge cone back-mixing, particle back-mixing is serious near the dust outlet geometry, which occupies 56.8% of total inlet particle mass flow rate. Particle which is smaller than 18μm can mix backward. The axial distribution of particle concentration decreases sharply in a range of 1.5 D (cyclone diameter) height above the dust discharge port. At last, only 2.6% of back-mixing particles with diameter no bigger than 13μm escape from vortex finder. This effect on separator efficiency increases with the particle diameter decreases.

scholarly journals On-Sun Performance Evaluation of Alternative High-Temperature Falling Particle Receiver Designs

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
Clifford K. Ho ◽  
Joshua M. Christian ◽  
Julius E. Yellowhair ◽  
Kenneth Armijo ◽  
William J. Kolb ◽  
...  
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Thermal Efficiency ◽  
Particle Temperature ◽  
Free Fall ◽  
Mass Flow Rates ◽  
Mesh Structures ◽  
Free Falling ◽  
The Impact

This paper evaluates the on-sun performance of a 1 MW falling particle receiver. Two particle receiver designs were investigated: obstructed flow particle receiver versus free-falling particle receiver. The intent of the tests was to investigate the impact of particle mass flow rate, irradiance, and particle temperature on the particle temperature rise and thermal efficiency of the receiver for each design. Results indicate that the obstructed flow design increased the residence time of the particles in the concentrated flux, thereby increasing the particle temperature and thermal efficiency for a given mass flow rate. The obstructions, a staggered array of chevron-shaped mesh structures, also provided more stability to the falling particles, which were prone to instabilities caused by convective currents in the free-fall design. Challenges encountered during the tests included nonuniform mass flow rates, wind impacts, and oxidation/deterioration of the mesh structures. Alternative materials, designs, and methods are presented to overcome these challenges.

Acoustic Analysis of Particle–Wall Interaction and Detection of Particle Mass Flow Rate in Vertical Pneumatic Conveying

2014 ◽  
Vol 53 (23) ◽  
pp. 9938-9948 ◽  
Author(s):  
Lelu He ◽  
Yefeng Zhou ◽  
Zhengliang Huang ◽  
Jingdai Wang ◽  
Musango Lungu ◽  
...  
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Acoustic Analysis ◽  
Particle Mass ◽  
Pneumatic Conveying ◽  
Wall Interaction

Performance Evaluation of a High-Temperature Falling Particle Receiver

2016 ◽  
Author(s):  
Clifford K. Ho ◽  
Joshua M. Christian ◽  
Julius Yellowhair ◽  
Kenneth Armijo ◽  
William J. Kolb ◽  
...  
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Thermal Efficiency ◽  
Particle Temperature ◽  
Free Fall ◽  
Mass Flow Rates ◽  
Mesh Structures ◽  
Free Falling ◽  
The Impact

This paper evaluates the on-sun performance of a 1 MW falling particle receiver. Two particle receiver designs were investigated: obstructed flow particle receiver vs. free-falling particle receiver. The intent of the tests was to investigate the impact of particle mass flow rate, irradiance, and particle temperature on the particle temperature rise and thermal efficiency of the receiver for each design. Results indicate that the obstructed flow design increased the residence time of the particles in the concentrated flux, thereby increasing the particle temperature and thermal efficiency for a given mass flow rate. The obstructions, a staggered array of chevron-shaped mesh structures, also provided more stability to the falling particles, which were prone to instabilities caused by convective currents in the free-fall design. Challenges encountered during the tests included non-uniform mass flow rates, wind impacts, and oxidation/deterioration of the mesh structures. Alternative materials, designs, and methods are presented to overcome these challenges.

scholarly journals Numerical Evaluation of Novel Particle Release Patterns in High-Temperature Falling Particle Receivers

2017 ◽  
Author(s):  
Brantley Mills ◽  
Clifford K. Ho
Keyword(s):  
High Temperature ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Thermal Efficiency ◽  
Elevated Temperatures ◽  
Particle Mass ◽  
Test Facility ◽  
Volumetric Heating ◽  
Particle Release

Novel particle release patterns have been proposed as a means to increase the thermal efficiency of high-temperature falling particle receivers. Innovative release patterns offer the ability to utilize light-trapping and volumetric heating effects as a means to increase particle temperatures over a conventional straight-line particle release pattern. The particle release patterns explored in this work include wave-like patterns and a series of parallel curtains normal to the incident irradiation that have shown favorable results in previous numerical studies at lower particle temperatures. A numerical model has recently been developed of an existing falling particle receiver at the National Solar Thermal Test Facility at Sandia National Laboratories to evaluate these patterns at elevated temperatures necessary to evaluate radiative and convective losses. This model has demonstrated that thermal efficiency gains of 2.5–4.6% could be realized using these patterns compared to the conventional planar release depending on the particle mass flow rate. Increasing the number of parallel curtains, increasing the spacing between curtains, and shifting the particle mass flow rate deeper in the receiver cavity was also found to increase the thermal efficiency. These effects became less significant as the particle mass flow rate increased.

Sign in / Sign up

Export Citation Format

Share Document