Study uses quantum chemical calculations
August 30, 2005
Rising oil prices reportedly are increasing the momentum to develop more efficient combustion systems.
But scientists say essential to that goal is a need to achieve greater understanding of the complex chemical reactions involved in combustion processes.
In one of the largest simulations ever focused on the problem, researchers at Pacific Northwest National Laboratory performed quantum chemical calculations to predict the heat of formation of octane, a key component of gasoline.
The calculation -- performed using 1,400 parallel processors -- took only 23 hours to complete and achieved a sustained efficiency of 75 percent, compared with the 5 percent to 10 percent efficiency of most codes. For comparison, the best one-processor desktop computer would have required three and a half years and 2.5 terabytes of memory to run the same calculation.
The pioneering calculations also helped identify the level of theory needed for subsequent efforts to reliably predict the heat of formation of larger alkanes in diesel fuel, for which there is very little experimental data.
Copyright 2005 by United Press International


