Performance of a Pebble Bed Thermal Storage Integrated with Concentrating Parabolic Solar Collector for Cooking

<table class="table-group" id="tab5"><tr><td><table class="table"><tr><td class="thead-hr" colspan="3"><hr/></td></tr><tr><td class="align_left"><svg height="14.3032pt" id="M82" style="vertical-align:-5.34108pt" version="1.1" viewbox="-0.0498162 -8.96212 87.8544 14.3032" width="87.8544pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M620 675H597C578 656 570 650 541 650H144C112 650 104 653 94 675H72C59 618 42 552 23 493L53 491C71 534 88 564 105 585C124 608 144 615 238 615H290L197 121C182 40 174 34 88 28L82 0H361L367 28C275 34 266 38 281 121L374 615H441C522 615 543 608 553 583C562 560 566 531 565 493L597 494C603 551 612 629 620 675Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,7.176,3.132)"><path d="M490 97L476 124C442 96 405 70 398 70C392 70 390 78 396 114C419 243 448 379 463 432L457 436C446 436 431 439 418 442C393 447 368 451 343 451C281 451 204 418 155 381C74 320 24 206 24 107C24 23 59 -12 88 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454C280 454 202 421 158 387C76 324 25 207 25 110C25 25 60 -12 90 -12C123 -12 159 4 197 34C241 69 294 126 328 171H330L314 86C298 0 313 -12 337 -12S429 24 496 96ZM375 388C374 372 365 306 350 267C332 211 193 56 146 56C133 56 117 74 117 123C117 224 161 332 224 382C244 397 276 404 304 404S362 397 375 388Z"></path></g><g transform="matrix(.0065,0,0,-0.0065,42.205,5.233)"><path d="M553 402C553 427 533 454 505 454C451 454 403 404 315 288L294 345C271 408 247 454 221 454C183 454 139 406 91 350L112 324C156 369 170 379 185 379C194 379 201 363 218 321L260 216C184 114 147 72 118 72C105 72 100 76 93 82S82 91 71 91C50 91 25 61 25 41C25 9 54 -12 79 -12C130 -12 183 29 277 173L317 66C336 15 366 -12 392 -12C429 -12 485 37 523 99L501 124C473 91 446 63 427 63C410 63 393 91 369 147L328 244C351 275 380 307 404 333S453 381 468 381C476 381 487 373 495 365C500 360 506 357 514 357C529 357 553 380 553 402Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,46.505,3.132)"><path d="M98 134C72 134 46 117 46 90C46 73 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635ZM243 598C332 598 358 454 358 312C358 173 334 26 245 26C158 26 128 174 128 313S152 598 243 598Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,72.531,3.132)"><path d="M283 271C283 451 220 610 70 710L48 683C146 603 207 443 207 271S149 -59 48 -142L70 -169C220 -67 283 90 283 271Z"></path></g><g transform="matrix(.013,0,0,-0.013,80.068,0)"><path d="M535 323V373H52V323H535ZM535 138V188H52V138H535Z"></path></g></svg> 20°C</td><td class="align_center">Space step = 0.1 m</td><td class="align_center">Time step <svg height="11.5564pt" id="M83" style="vertical-align:-2.26807pt" version="1.1" viewbox="-0.0498162 -9.28833 21.9432 11.5564" width="21.9432pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z"></path></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M600 0V24L339 665L311 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290Z"></path></g></svg>,</span><sub>11 hours charge</sub></td><td class="align_center">Number of space step = 10</td><td class="align_center"><i>t<sub>max</sub></i> = 11 hours</td></tr><tr class="table-tr"><td colspan="3"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>Initial and boundary conditions for discharging process.</div>

Journal of Renewable Energy

tab5

Table 5

Table 5: Performance of a Pebble Bed Thermal Storage Integrated with Concentrating Parabolic Solar Collector for Cooking 