Export data from Array to *.csv without curly brackets

Question

I have a couple of *.csv files containing data from several experiments. From those, two columns shall be extracted each, to form a new list. This process shall be automated to collect all the data from all experiments of one series. For this I try to use an indexed variable a[i]. With Transpose and Array the desired list is created. But when I try to export my test case to a *.csv it contains those curly brackets and quotation marks (the first two lines contain strings). Within this forum a number of people suggested to use Flatten to get rid of the unwanted characters. This works but completely destroys the structure of the table, which I want to keep.

When I use Join on my testcase there are no brackets or quotation marks in the *.csv. But as far as I understand the indexed variables are better for my task since the number of experiments within the different series will change. This assumption is based on answers of the following thread: https://stackoverflow.com/questions/11783760/how-do-i-save-multiple-variables-with-an-iterated-name-in-mathematica

I suppose it might be "just" an issue with the data format. Because it looks like Mathematica is exporting the list instead of the values within the list itself. Unfortunately I can't figure out how to fix it.

Thank you in advance!

--Edit 1--

Here is a code example of my problem. I hope this helps better understanding the problem.

I'm importing the *.csv files to the indexed varibale, using colums 1 and 4.

heatcombarrayex[1] =
    Part[
        Import[
            TemplateApply[NotebookDirectory[] <> StringTemplate[
                newfilename <> "_``"][ToString[1] <> "-" <> ToString[1]]] <> 
                "\\" <> TemplateApply[StringTemplate[
                newfilename <> "``"][ToString[1] <> "-" <> ToString[1]]] <> 
                "_devc.csv"], 
    All, {1, 4}];

Then I use Array to show all the entries of the indexed variable. For my testcase I use two entries.

heatcombarrayoutex = Transpose[Array[heatcombarrayex, 2]];

Then the data is exported to a *.csv again.

Export[TemplateApply[
  NotebookDirectory[] <> 
   "heatcombarrayex.csv"], heatcombarrayoutex, "CSV"]

This shows the first four lines of the result (Also I realised that I forget to mention that the second column is also wrapped in qoutation marks.):

{s", "kW/kg"}","{"s", "kW/kg"}" {Time", "hrrpum"}","{"Time", "hrrpum"}" {0., 0.},"{0., 0.}" {4.21, 0.033500582},"{4.21, 0.041624561}"

And this is how it should look like:

s,kW/kg,s,kW/kg Time,hrrpum,Time,hrrpum 0.,0.,0.,0. 4.21,0.033500582,4.21,0.041624561

So the question is: How to get rid of those extra characters?

-- Edit 2 --

For the the test case I use two data files (which can be found via the added link). But I only posted the code to import file number one, since the code for the following is basically the same, just the number changes.

In Mathematica the heatcombarrayoutex looks like this:
{{{"s", "kW/kg"}, {"s", "kW/kg"}}, {{"Time", "hrrpum"}, {"Time", "hrrpum"}}, {{0., 0.}, {0., 0.}}, {{4.21, 0.0335006}, {4.21, 0.0416246}}, ...995..., {{4200., 0.}, {4200., 0.}}}

I have two example files included for importing, which can be found following this link

Answer 1

Here is an answer using a small amount of the two example data files you supplied.

Read the first 4 lines of each file:

 h = Import[#][[1 ;; 4, {1, 4}]] & /@ FileNames["/SampleData/Heat*"];

Transpose, flatten and export the data:

Export["/SampleData/heatcombarrayex.csv", Flatten/@Transpose@h]

The issue you were having is that when you transpose your data, you have nested lists which are represented in CSV format in bracketed form.

{{{"s", "kW/kg"}, {"s", "kW/kg"}}, {{"Time", "hrrpum"}, {"Time", "hrrpum"}}, {{0., 0.}, {0., 0.}}, {{4.21, 0.0335006}, {4.21, 0.0416246}}}

You need to remove that nesting by using Flatten.

{{"s", "kW/kg", "s", "kW/kg"}, {"Time", "hrrpum", "Time", "hrrpum"}, {0., 0., 0., 0.}, {4.21, 0.0335006, 4.21, 0.0416246}}

And the contents of the exported file:

s,kW/kg,s,kW/kg Time,hrrpum,Time,hrrpum 0.,0.,0.,0. 4.21,0.033500582,4.21,0.041624561