The German manufacturer will return to the grand prix fold for the advent of the new engine regulations that notably ditch the expensive and complex Motor Generator Unit-Heat (MGU-H).
Audi reports that since the end of last year, a one-cylinder mule engine has been tested. But in time for 2024, it expects to have a complete 1.6-litre turbo hybrid powertrain ready to run on a dyno.
To aid that project, 39-year-old Jani - who previously tested for Sauber and Red Bull - has been signed to assist the simulator programme run from the Neuburg engine plant.
Jani, who won the 2016 World Endurance Championship for Porsche ahead of breaking the lap record at Spa aboard the 919 Hybrid Evo project, said: "I am delighted to accompany Audi on their way into Formula 1.
"It is both an honour and a great responsibility to be involved in a project of this magnitude at an early stage.
"I am sure that with my experience from Formula 1 and LMP projects I can forge good links between theory and practice."
Neel Jani, Porsche GT Team
Photo by: Porsche Motorsport
Swiss driver Jani has previous for being heavily involved in fledgling motorsport programmes to run under the Volkswagen Group umbrella. Alongside Andre Lotterer, he led Porsche for its first foray into Formula E in the 2019-20 season.
Audi technical development boss Oliver Hoffmann added: "Just like in production development, simulation plays a major role in our Formula 1 project.
"Our simulator is an important tool for the power unit development. It requires a development driver who in addition to a grasp of technology brings versatile experience to the project, especially in terms of energy management in racing conditions."
Audi will enter F1 as a true works outfit in 2026 as it completes its majority takeover of the Sauber outfit in Hinwil. Ex-Porsche LMP1 boss and former McLaren team principal Andreas Seidl will lead the operation.
The German has recently re-signed James Key as technical director after the Brit was ousted by McLaren. His exit followed a thorough review of the Woking team's design leadership structure, which was overseen by Seidl's replacement Andrea Stella.
Audi CEO Markus Duesmann during the Audi press conference at Auto Shanghai 2023
Photo by: Audi Communications Motorsport
Adam Baker, the chief executive of Audi Formula Racing, said of the firm's progress towards 2026: "At the moment, we are mainly focused on fundamental concept questions with high relevance to performance.
"However, in evaluating various technical solutions we rely not only on digital methods. Know-how, experience and practically relevant development are indispensable elements of drawing the right conclusions from the simulation.
"With that combination, we can assess various operating strategies at an early stage and pave the way for efficient energy management of the power unit."