Understanding old JAVA code

Question

I have a code here at the company and I need to understand what it really does. By the method Name I found that it removed the characters outside the UTF-8 pattern or something like that, giving an analysis I saw that it does not exactly anything in the string I step. I need someone to explain to me what this code really does or give me some hint about it so I can judge whether I remove or create something better.

public static String replaceUTF8(String text) {
    String[] REPLACES = {"a", "e", "i", "o", "u", "c"};
    Pattern[] PATTERNS = new Pattern[REPLACES.length];
    PATTERNS[0] = Pattern.compile("[?????]", Pattern.CASE_INSENSITIVE);
    PATTERNS[1] = Pattern.compile("[????]", Pattern.CASE_INSENSITIVE);
    PATTERNS[2] = Pattern.compile("[????]", Pattern.CASE_INSENSITIVE);
    PATTERNS[3] = Pattern.compile("[?????]", Pattern.CASE_INSENSITIVE);
    PATTERNS[4] = Pattern.compile("[????]", Pattern.CASE_INSENSITIVE);
    PATTERNS[5] = Pattern.compile("[?]", Pattern.CASE_INSENSITIVE);
    String result = text;
    for (int i = 0; i < PATTERNS.length; i++) {
        Matcher matcher = PATTERNS[i].matcher(result);
        result = matcher.replaceAll(REPLACES[i]);
    }
    return result;
}

NOTE : It is an old code and is used in various places of the system, I need to really understand why of existence and if it will not affect if I remove or modify it.