A MATHEMATICIAN whose influential research on engineering has been used by the world’s leading gas companies, has died aged 91.

Ruth Rogers, who lived in Lewes, was one of the two female academics in the new science faculty at the University of Sussex in the Sixties.

She spent most of her career at the university.

She taught at the School of Mathematics as a lecturer in 1962, later becoming a reader.

Dr Rogers’s main interest was solving important engineering problems.

More specifically, she specialised in fluid mechanics, which is a study of forces and flow within liquids.

Dr Rogers studied meteorology and engineering and it was these studies which she was able to make some of her most valuable contributions. Her research into the mechanics and forces inside the internal cooling air systems of gas turbines proved they are driven by rotation and temperature gradients.

Dr Rogers published two monographs and numerous papers which became theoretical models used by engineers in gas turbine companies across the world.

She was born in Kingston, Surrey. Her father, John Rogers, was a grocer and her mother was Dorothy, nee Biffen.

She attended Tiffin Girls’ School from 1937 to 1941.

When her parents moved to London, she went to Chiswick County Girls School from 1941 to 1945.

Her parents were Plymouth Brethren but Dr Rogers did not follow the religion and became an atheist before converting to Church of England in her thirties. Dr Rogers studied a Bachelor of Science in mathematics and physics at Queen Mary College and University of London in 1948.

In 1953, she gained a PhD researching in dynamic meteorology.

She lectured at the universities of London and Manchester and at the University College of Wales. She worked as a senior scientific officer at the Royal Aircraft Establishment in Farnborough for three years.

Because of Dr Rogers’s knowledge and interest in rotating fluids, she became a partner for research with academics at the Thermo-Fluid-Mechanics Research Centre (TFMRC) in Sussex.

Her main research focused on design of gas turbines. In 1982, Dr Rogers retired.

She continued to teach part time and did research and co-authored monographs on flow and heat transfer in rotating disc systems, published in 1995.

Dr Rogers also enjoyed travelling, Sudoku and genealogy.