$chunk->process() in a loop

<?php
$childs = $modx->getCollection('modResource',array('parent' => $parentId));

$chunk = $modx->getObject('modChunk', 1);

$output = '';
foreach ($childs as $child) {
    $output .= $chunk->process($child->toArray());
}

return $output;

foreach ($childs as $child) {
    $chunk->setCacheable(false);
    $output .= $chunk->process($child->toArray());
}

$modx->getChunk('chunkName', $child->toArray());

$chunk = $modx->parser->getElement('modChunk', 'chunkName');

$chunk->setCacheable(false);

$chunk->setCacheable(false);

$chunk = $modx->parser->getElement('modChunk', 'chunkName');

$modx->getChunk('chunkName', $child->toArray());

$useChunk = $modx->getObject('modChunk', 1)->get('content');
$chunk = $modx->newObject('modChunk');
foreach ($childs as $child) {
    $output .= $chunk->process($child->toArray(), $useChunk);
}

toArray('', true);

$child->getTVValue('tvname')

$tvr = $modx->getObject('modTemplateVarResource', array('tmplvarid' => $tvId, 'contentid' => $child->get('id')));
if ($tvr) {
    $value = $tvt->get('value');
}