PHP array filled by a MySQL query [closed]

Question

I need to fill multiple different arrays by using a MySQL query. This would have up to 16 different arrays. I want to specify each array with a number at the end. so $resultmm17, $resultmm18, and so on. I want to do this with a for loop. If I try to do a var_dump($resultmm17), I get an HTTP 500 error on the current code.

$indexval = 1;
for ($i = 0; $i < $row[4]; $i++) {
    $aa = 17;
    $fannn = "SFan".$indexval;
    
    $query12 = "SELECT * FROM vibrationinfo2 
         WHERE unitserial = '$serial' 
           AND component = '$fannn' ORDER BY value2 DESC";
    $result12 = mysqli_query($link, $query12);

    ${'resultsmm'.$aa} = array();
    ${'hertzcalculated'.$aa} = array();
    while ($row12 = mysqli_fetch_assoc($result12)) {
        ${'resultsmm'.$aa}[] = $row12['value3'];
        ${'hertzcalculated'.$aa}[] = $row12['value2'];
    }

    $indexval++;
    $aa++;
}