INTRODUCTION

The first piston engine was developed in 1690 by the French physicist and inventor Denis Papin and was utilised for pumping water. Papin’s engine, which was small a lot more than a curiosity, was a crude machine in which the actual work was completed by air rather than steam pressure. It consisted of a single cylinder that also served as a boiler. A modest quantity of water was placed in the bottom of the cylinder and heated until steam was formed. The pressure of this steam raised a piston fitting in the cylinder, and, following it was raised, the source of heat was removed from the bottom of the cylinder. As the cylinder cooled, the steam condensed and air pressure on the upper side of the piston forced the.

In 1698, the English engineer Thomas Savery built a steam engine that utilized two copper vessels alternately filled with steam from a boiler. Savery’s engine was employed for pumping water, but could only raise water about 6 m (20 ft) without having employing pressures which risked explosion, and was rapidly abandoned. The first practical steam engine, the so-referred to as atmospheric engine, was built by the English inventor Thomas Newcomen in 1712. This device had a vertical cylinder and a piston that was counterweighted. Steam admitted to the bottom of the cylinder at really low pressure acted with the counterweight to move the piston to the best of the cylinder. When the piston reached this point, a valve opened automatically and sprayed a jet of cold water into the cylinder. The water condensed the steam, and atmospheric pressure forced the piston back to the bottom of the cylinder. A rod attached to the arm of the pivoted beam that connected piston and counterweight moved up and down as the piston moved, actuating a pump. Newcomen’s engine was not effective, but it was sufficiently practical to be used extensively for pumping water from coal mines. http://scienceandnatureintheworld.blogspot.com