Please remember that acronyms should only be used for words or phrases that are repeated a number of times throughout your document.
If you use too many initialisms and acronyms, readers will become confused.
While "N" is a consonant, it makes the sound (i.e., a vowel sound) when you say it. It's also important to remember that while you can sometimes make up initialisms or acronyms, there are many words/phrases that require abbreviating that are already established and universal.
There are a number of online dictionaries you can use to search for commonly used initialisms and acronyms.
After you've established an initialism or acronym in your paper, you must consistently use the short form in place of the words.
Always clarify in your own mind the exact definition of each acronym you use.
There is a time and place for everything and using initialisms and acronyms is no exception.
The whole point of using these forms of abbreviation in your business writing is to make your writing clearer.
Some abbreviations may not be in the dictionary but appear frequently in the journal for which you are writing.
Although probably well understood by many readers, these abbreviations should still be explained when first used.