In 1895 he joined B&W as chief mechanical engineer.
He was promoted to Director of the engine department in 1897 where he started a comprehensive modernization.
Knudsen realised the potential of the diesel engine as ship propulsion and traveled to Germany to meet Rudolf Diesel who was testing the new engines at MAN AG in Augsburg.
Consequently B&W obtained the patent rights on the Diesel engine for Denmark.
The following years saw numerous tests and improvements, eventually resulting in an efficient and reliable machine.
In 1908 Knudsen became the head of both the machine factory in Christianshavn and the shipyard in Refshaleøen.

Hans Niels Andersen, founder of the East Asiatic Company, saw that diesel powered ships would mean a leap forward for the shipping industry, and in December 1910 placed an order with B&W for a large oceangoing motor ship, the MS Selandia.

The first voyage in February 1912, with Andersen and Knudsen on board, was from Copenhagen to Bangkok via London and Antwerp.
The ship was received with great interest and many people visited the Selandia including the First Lord of the Admiralty, Winston Churchill, and other high ranking naval officers.

Selandia had two sister ships, the MS Jutlandia and the MS Fionia; finishing their sea trials in June 1912, and July 1912, respectively.
The Fionia was met with similar interest in Germany during Kiel Week, where visitors included German Emperor Wilhelm II and Albert Ballin, director of the Hamburg America Line.

Knudsen resigned from the yard's daily management in April 1919, joining the company's board as an advisor.
In 1895 he joined B&W as chief mechanical engineer. He was promoted to Director of the engine department in 1897 where he started a comprehensive modernization. Knudsen realised the potential of the diesel engine as ship propulsion and traveled to Germany to meet Rudolf Diesel who was testing the new engines at MAN AG in Augsburg. Consequently B&W obtained the patent rights on the Diesel engine for Denmark. The following years saw numerous tests and improvements, eventually resulting in an efficient and reliable machine. In 1908 Knudsen became the head of both the machine factory in Christianshavn and the shipyard in Refshaleøen.
Hans Niels Andersen, founder of the East Asiatic Company, saw that diesel powered ships would mean a leap forward for the shipping industry, and in December 1910 placed an order with B&W for a large oceangoing motor ship, the MS Selandia.
The first voyage in February 1912, with Andersen and Knudsen on board, was from Copenhagen to Bangkok via London and Antwerp. The ship was received with great interest and many people visited the Selandia including the First Lord of the Admiralty, Winston Churchill, and other high ranking naval officers.
Selandia had two sister ships, the MS Jutlandia and the MS Fionia; finishing their sea trials in June 1912, and July 1912, respectively. The Fionia was met with similar interest in Germany during Kiel Week, where visitors included German Emperor Wilhelm II and Albert Ballin, director of the Hamburg America Line.
Knudsen resigned from the yard's daily management in April 1919, joining the company's board as an advisor.
Ivar Knudsen