I've done research work entirely at home, it is completely unrelated to my thesis. I am going to publish it in some journal.
Although I am aware that I should not use my affiliation, and it is possible to publish without it, I am unsure about if it would turn into a disadvantage in the following sense: 1) Chances to be accepted for publishing (In real world!). 2) Perceived value of the work (for example, for future opportunities to obtain a post-doc position).
Also, the work could not be done in the same way, if someone close to me has not lent me his personal computer (which is far more powerful than mine, but a regular PC) for few days. Does it look unprofessional to add acknowledgement to "Mr. X" (instead an institution) for providing the computational resources? Considering that, no unusual computational resources are needed (an ~400/500 USD PC in US), in a field where most first world research groups have very high computational power.
I know how it should be in theory, but I am looking for sincere answers about how (in real world) the worldwide scientific community perceive about it, for both, chances of publication and future jobs. Any interesting consideration that I did not notice is welcome.
Edit: Currently I am doing my PhD in a research institute which depends on one of the more recognized universities of my country. I have already published using this affiliation and using it wouldn't be a problem.
No one will know that you are unaffiliated since you are free to put your research institute as an affiliation. Your institute might even be upset if you don't since you did this work while in their employment even if your contract doesn't give them rights to it if done on your own time at home using equipment that does not belong to them. If you put them as your affiliation, someone will eventually notice and may come asking questions. As such, it would probably be best to show this work to your employer through your current line manager/PhD supervisor and ask for their advice. It's likely that with some help you and your advisor will be able to publish this article together. This is how it works in the "real" world.
My favorite publication of my own was mostly done at home and in notebooks I bought myself while a student. I eventually passed it by my PhD advisor, he made some edits and suggested some changes, helped rewrite the introduction and conclusions, checked the math, and we eventually published a paper together. It was a very satisfying way to bring my side-project to a close. The material never even appeared in my dissertation (as I didn't do a so-called stapler thesis).