The move comes as the society attempts to garner more respect for the engineering profession.
It is seeking to position itself as an expert in the media on issues relating to the occupation, particularly railway and road safety.
'Our focus will be on PR for the first time,' said Clarke, who reports to chief executive Tracey Shelley.
She added that in the past, the society had steered most of its comms efforts towards driving membership.
'No one really knows what the society is - certainly not the general public,' Clarke said, adding that a priority would be to 'improve the reputation of engineering as a profession' and advocate women entering the sector.
'Engineering gets overlooked, possibly because there are so many different types of engineering. If more people understood what engineering was, engineers would be more respected for their contribution to industry,' she said.
Clarke replaces Katrina Macgregor, who left in April to join the Engineering Employers Federation.
Clarke will be responsible for media relations, marketing, external stakeholder relations, internal comms, events and the website.