My answer is late, but i want to add some information that is missed in all above answers.
1) If you want to select single value in chosen select.
$('#select-id').val("22").trigger('chosen:updated');
2) If you are using multiple chosen select, then may you need to set multiple values at single time.
$('#documents').val(["22", "25", "27"]).trigger('chosen:updated');
Information gathered from following links:
1) Chosen Docs
2) Chosen Github Discussion