When Thomas Newcomen began his first experiments in 1705, many people advised him to do otherwise. He was a simple smith and iron trader. Newcomen consistently thought about Papin's idea of an engine with a free piston. Although many people were dubious and considered it to be impossible to design a piston with a sufficient sealing, he began his work and in 1712 he presented his first engine, which immediately began its work in a mine .
An important advantage of Newcomen's engine compared to Savery's engine is that its power did not depend on the steam pressure but on the quantity of the cylinder. Because of this it was called low pressure steam engine.
Althought the engine needed an enormous amount of coal to work there were some attemps to improve the atmospheric engine. One of the first improvements was the invention of the injection condensation. In this case, the cooling water did not flow over the cylinder, but it was injected directly into the cylinder. The effect was a much faster condensation. Another improvement was the introduction of an automatic control. However, the efficiency was still very low. Much coal was used for just poor power.
John Smeaton was one of the best engineers of his time. He began to optimize Newcomen's engine. He studied, first of all, every detail of the engine and made some experiments with this. Smeaton came to the conclusion that the engine lost much energy because of bad cylinders with unsufficient sealing. In addition, the measures of the parts did not match with each other, e.g. the boiler was often too small compared with the cylinder to produce enough steam. He could design engines that worked very well because of better sealings and better measures of the parts.
Conrad Matschoss - Die Entwicklung der Dampfmaschine
Robert H. Thurston - The growth of the steam-engine (online)
F.Calcagno & S.M. Calizzano - Steam engines (online)
© 2000 by ThinkQuest team C006011