Dirani will step into Enrico Toccacelo's vacated seat at Victory Engineering, after the Italian left the team to concentrate on his Formula One aspirations with Minardi.
The Brazilian has already won at the British circuit this season, having taken both races at the opening rounds of this year's British F3 series.
Dirani told Autosport-Atlas: "I'm just trying out the series to see if I want to do it next year. It was one of the options before I started the year but we couldn't raise the budget so I went to F3.
"Knowing Donington Park well will mean I can evaluate the car, which will be the fastest thing I have ever raced. I'll get three hours of testing before qualifying so I can do my best to try and get used to the car and see what I can do."
Dirani's signing is one of a number of changes for this weekend's meeting. RC Motorsport have signed its former World Series light driver Matteo Pellegrino, who has raced in the 3000 Pro Series this season.
Pellegrino replaces Karun Chandhok, who is not returning from his three meeting ban and instead is concentrating on his A1 Grand Prix duties for Team India.
Eurointernational have yet to confirm their replacement for Giorgio Mondini, who has graduated to GP2.
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