Fig. 1 Particle egress captured from the falling particle receiver aperture during testing. The plume can be observed within the region inside the rectangle on the left half of the image. More

Fig. 2 Irradiance incident on the aperture of the falling particle receiver. As it can be observed, based on the irradiance level desired, there may be heat flux spillage on from the 2-m diameter spot [ 12 ]. More

Fig. 3 Diagram of a multiple particle inside a pixel. Note: There could be one or more particles inside every pixel. More

Fig. 4 Diagram of outlying the progression of the calculation in the model. The opacity, background temperature, and pixel temperature are values obtained from the images captured from the cameras. These values are then used to calculate the expected particle irradiance. Knowing this value, the tr... More

Fig. 5 Experimental setup at UNM composed of a SPR, an actuated tube furnace, and a solar simulator More

Fig. 6 Left: components of the small particle receiver. Top and bottom hoppers instrumented with thermocouples, a 0.5-g resolution scale to record the mass flowrate of the particle curtain, a flow mesh to increase the uniformity and decrease the opacity of the curtain, and an LED panel to generate... More

Fig. 7 Graphical representation of the numerator calculation on the opacity equation (Eq. (9) ) More

Fig. 8 Graphical representation of the entire calculation on the opacity equation (Eq. (9) ). The result of the calculation is the same image as Fig. 7 ; however, the values range from 0 to 1 for opacity. More

Fig. 9 The average opacity as a function of discharge position can be obtained by discretizing the resulting image from the calculation in Fig. 8 into sub-regions of a discrete size. The error bars on the empirical values represent 1 − σ from the mean for every sub-region. More

Fig. 10 Left: sample thermogram from a curtain preheated to 200 °C. Right: once the thermograms are imported into matlab , the average apparent temperature profile is generated by averaging every row of the thermogram for the 554-thermogram sequence. Similarly, these profiles corresponding to ind... More

Fig. 11 Comparison of the empirically derived profile (line) and the extracted tempreatures using the Stefan–Boltzmann's (dark gray circles) and Planck's (light gray circles) model for a preheat temperature of 200 °C considering only the region of interest [ 20 ] More

Fig. 12 Comparison of particle temperature profiles for carbo and sand particles preheated at different temperatures. The measured temperature represents the profile developed using the empirical lumped capacitance model. The extracted temperature values are comparable to those from the empirical ... More

Fig. 1 The schematic: ( a ) industry-scale ASF and ( b ) retrofitted SCF [ 18 , 19 ] More