The top-seeded Australian, who won the first title of his career in Adelaide ten years ago, needed just 65 minutes to record his opening win of the new season.
Former Wimbledon and U.S. Open champion Hewitt has been working hard over the past two months under the tutelage of his new coach Tony Roche and he was far too good for Sela, the world number 64.
On a day when temperatures were just under 40 degrees Celsius (104 degrees Fahrenheit), Hewitt produced an impressive performance as he set up a clash with Argentine Jose Acasuso or Alejandro Falla of Colombia.
Second-seed Paul-Henri Mathieu beat fellow Frenchman Julien Benneteau 7-6, 7-5 in a first-round match that lasted two hours, 22 minutes.
Mathieu, who ended the year at a career-high ranking of 25, will play Australian wildcard Chris Guccione in the second round.
The tall left-hander, runner-up in Adelaide last year, hammered 23 aces as he beat Wayne Odesnik 7-5, 7-6.
Third seed Jarkko Nieminen enjoyed a comfortable 6-2, 6-4 victory over Ivo Klec of Slovakia.
The Finnish left-hander said competing in Adelaide was the perfect preparation for this month's Australian Open, which begins in Melbourne on Jan 14.
"You have to be careful not to practice too much as the matches take a lot out of you," he told reporters.
"All the players seem to have prepared well at home, as everyone know it is hot here. That is why I start competing in Adelaide, because it is hot, as it really prepares you for Melbourne."
However, eighth seed Sebastien Grosjean suffered a shock defeat as he was ousted 4-6, 6-1, 6-3 by veteran American Vince Spadea.
French sixth seed Jo-Wilfried Tsonga and Russian Evgeny Korolev also advanced to round two.
