Bell was announced in the new role on Wednesday shortly after it emerged that he had left Alpine, where he had been working on non-F1 projects.
Alonso worked with Bell through his first two stints at Renault, including his world championship-winning seasons in 2005 and 2006, when the Ulsterman was the technical director.
When Alonso returned to the renamed Alpine team in 2021, Bell was again present in the Enstone camp as an advisor.
He has now taken up a newly-created role at an organisation that already had a strong technical structure in place.
"Always when more people come to the team, there is not really any disadvantage, to be honest,” said Alonso when asked by Motorsport.com about the new arrival.
“There is always an advantage. And the problem is to convince everyone to work together as a team, and as a group.
“So that's the role also of Martin [Whitmarsh], and the role of Lawrence [Stroll] as a leader. I think we have a great technical group of people and great leadership as well. So step-by-step, hopefully, creating a bigger team."
Asked about his earlier relationship with Bell, he said: "Bob was taking a very different role back then, in the two championship years. Now he was more into special projects [at Alpine], I understood.
“But that those kinds of senior role people, they bring always background knowledge about how to run a competitive team, and how to have a good structure in the factory.
“So the contribution of Bob hopefully brings Aston into a better level, and that's the aim, so I'm happy to welcome him.”
Regarding the team’s current form, Alonso said the team was better in qualifying in Bahrain and worse in the race than has been anticipated, with the Spaniard slipping from sixth on the grid to ninth at the flag.
With team-mate Lance Stroll recovering from an early incident to finish 10th, the Silverstone team was clearly benchmarked as having the fifth-fastest car.
"Probably it was a bit of a surprise how fast we were on Friday,” he said. “And we were really surprised how far we were on Saturday. So both ways in Bahrain [we] were a little bit one in the positive way, one in the negative.
“So we need to understand what we can do better, especially for Sundays. We were fifth fastest in Abu Dhabi [last year]. We remain fifth fastest in Bahrain. So more or less we made the same progress as everyone in the winter, which maybe was as expected.
“Now it's up to us to really bring that pace to the car in in a better way than what we did last year. We learned a lot of things. Hopefully we can apply those learnings into this year."
However, he is not expecting to see the team improve on fifth place in the pecking order in Jeddah this week.
"The cars are identical to Bahrain,” he said. “I know that there is the need to talk about the performance, and the need to talk about something that can change the domination from Red Bull.
“But this is F1, this is not a simple sport. This is much more complicated. I don't see any difference from Bahrain to here.
“Hopefully we see a better result from Aston Martin, we were very fast last year. So hopefully set-up wise adaptation to the track can be better than Bahrain. But we should be the fifth fastest team, I don't expect any miracle."
Alonso says that Aston was worse off than rivals on tyre degradation in Bahrain, but he says it will be less of an issue for everyone in Saudi Arabia.
"There will be lower degradation here,” he said. “Last year it was one of the lowest degradation circuits of the calendar, Jeddah, only one stop in the previous editions here.
“So there will be less degradation for everybody, but the better car you have, the more downforce you have, less degradation, because you slide less the tyres.
“So this is what we need to do, improve the car, get more grip, and the tyres will suffer less."
