Page 68 - Spring 2015

Dr. Per V. brüel -100 Years
Per Brüel was charismatic, bright, and fast thinking, abilities he preserved to the present day. He was also a world-class engineer, who still could suggest surprising engineering so- lutions to sound and vibration problems. I first met Brüel in 1964 when he invited the participants in a NATO Advanced Study Institute on Underwater Acoustics and Signal Process- ing to visit the factories in Nærum. Per personally showed us around in the factory, and I was strongly impressed by his lively presentation of instruments and their qualities, his knowledge on sound and vibration, and his dedication to all aspects of acoustics. This meeting in 1964 led to a great friendship that developed over the subsequent years through travels to conferences and family parties.
Per Brüel was a member of the board of directors for Brüel & Kjær A/S from 1942 and to 1991, and he was a member of the board of directors for a great number of subsidiary companies in many countries. He was also a member of the Council for the Danish National Bank. His great interests in aviation made him obvious as a member of the Contact Committee for General Aviation, as chairman of the Council for Motorised Airplanes, and as a vice president for Federa- tion Aèronautique Internationale. With Per’s deep knowl- edge about aircraft noise, he contributed to ISO standards on this topic, and he was for many years a member of stan- dardization committees for a long series of standards on as- pects of sound and vibration. He also received the Aviation Cup for distinguished contributions to aviation (Figure 2).
Automobiles were also an interest of Per’s. In fact, he took part in several car races for vintage cars. While Nielsen used a Jaguar, Per had a Fiat 500. When he was asked why he pre- ferred the small Fiat to other more comfortable company cars, he replied that the comfort in a Fiat 500 was so poor that he could keep the car for himself because nobody in the company would ever ask him for a lift.
All Per’s important scientific and technical contributions to sound and vibration over more than 75 years brought him recognition from many universities and scientific organiza- tions. He was a member of the Danish Academy of Technical Sciences and a member of the National Academy of Engi- neering in the United States with the citation: “Development and production of precision acoustical and vibrational mea- suring instruments.” In 1987, the American Society of Me- chanical Engineers (ASME) established a “Per Brüel Gold Medal” for Noise Control and Acoustics. This medal honors Dr. Per Brüel for pioneering the development of sophisti- cated noise and vibration measuring and processing equip-
ment. It is given in recognition of eminent achievement and extraordinary merit in the field of noise control and acous- tics. He was also a Distinguished Member of the Institute of Noise Control Engineering of the United States. Moreover, he received honorary professorships and doctor degrees from many universities.
Unfortunately, Brüel & Kjær A/S started to have financial problems at the end of the 1980s. In July 1992, the company was sold to the German holding company AGIV. Far into the normal retirement age, Per Brüel started his new com- pany, Brüel Acoustics. In the new company, Brüel continued his activities involving the development of instruments and of technologies for measurement of the masking of speech, the propagation of step noise, the intelligibility of speech, the sound pressure, and absorption coefficients, and he was fighting for getting the IEC standard for A-weighting of noise measurements abolished. Instead, the standard should be Kryter’s D-weighting curve.
Dr. Per V. Brüel, who turned 100 years, preserved his leg- endary energy, and the strong admiration he enjoyed among acousticians all over the world for his many and decisive contributions to sound and vibration is unchanged.
biosketch
Leif Bjørnø (pictured (right) with Dr. Brüel at 100th birthday party) Professor & Profes- sor h.c., Dr. Phil. h.c., Ph.D., DIC. Born 1937 in Svendborg, Den- mark. He was professor
of Industrial Acoustics at the Technical University of Den- mark from 1978 – 2000. He is a Fellow or Honorary Member of several international learned societies, and he has received honorary degrees, medals and prizes from a substantial num- ber of universities around the world. He has been chairman or member of the board of directors for several industrial companies in Denmark and abroad, 1980-2013.
References
Brüel, P. V., and Ingård, U. (1949). A new high speed level recorder. Journal of the Acoustical Society of America 21, 91-93.
Kryter, K. D. (1970). The Effects of Noise on Man. Academic Press, New York.
66 | Acoustics Today | Spring 2015