Bowen was born in Cockett, near Swansea in 1911 and educated at the University of Wales (Swansea) and King's College, London, where he completed his doctorate under Professor Edward V. Appleton. As part of his doctoral research, Bowen spent much of 1933 and 1934 working with a cathode-ray direction finder at the Radio Research Station at Slough and it was there that he was noticed by Robert Watson-Watt. In 1935 Bowen was recruited by Watson-Watt as a Junior Scientific Officer in his Radar Development Team.

Towards the end of 1935 Watson-Watt's team moved to the Air Ministry Research Station, Bawdsey Manor. Bowen, at his own request, was assigned to tackle the highly speculative - and at that time unique - venture of putting radar in an aircraft.

In August 1940 Bowen left the UK as one of seven members of a Mission, led by Sir Henry Tizard, to disclose recent British technical advances to the USA and Canada. Bowen's job was to tell them all about British radar. He took with him not only information on all existing and projected equipment, but also an early sample of the cavity magnetron, the essential and highly secret key to the development of centimetre-wave radar that had just been invented.

Bowen served at the British Air Commission, Washington, until 1942, and then at the Radiation Laboratory, MIT, in 1943. He was subsequently invited to join the CSIR (O) in Australia in 1943 and became the Chief of the Division of Radiophysics in Sydney, 1946-71. There he encouraged the new science of radioastronomy and brought about the construction of the 210ft radio telescope at Parkes, New South Wales. He mounted a remarkable effort to improve the rainfall in (dry) Australia, which began in 1947 and continued after he retired in 1971. After his retirement he also served as Counsellor (Scientific) at the Australian Embassy in Washington D.C., USA, 1973-76.

He published, "A Textbook of Radar" (1954) and "Radar Days" (1987).

He was awarded the OBE in 1941, the American medal of freedom (for contributions to the US war effort in 1947, and the CBE in 1962. In 1975 he was elected a Fellow of the Royal Society. He died in 1991.