What tense in a scientific paper

I am currently writing my first scientific paper and therefore I am wondering which tense I should use in it.

I'd tend to use a future tense, but present perfect seems to be suitable as well.

e.g.

[In the first part of this paper, we will study how ...]

or

[In the first part of this paper, we have studied how ...]

Generally, scientific papers are written in the present tense, with past tense used to describe the experiments that were done during the research, and future tense reserved for planned future work.

Here is a writing style guide from Nature that gives more detailed explanations about tenses.

There are several conventions about the use of tense that vary between authors, and may vary between scientific disciplines. For example, previous work done by other researchers can be reported in past tense or in present perfect tense. I would suggest looking at several papers in your discipline to see how they use tenses.