Invention and application of steam engine

History has endowed the people of China with four great inventions, thus establishing an ancient civilization with a thousand years. History has given the invention of the steam engine to the west, and western civilization has been ahead of the world for more than one hundred years. In fact, the invention of the steam engine embodies the hard work and wisdom of many western inventors ... Papen's original steam engine. Since the beginning of17th century, scientists from Italy, Britain and France began to study steam. Some steam-driven devices came out one after another. By the end of17th century, a French technician named Papen had built the world's first primitive steam engine. Papen's steam engine has a cylinder and a piston. Its working principle is sufficient: by heating the water injection well in the cylinder, when the water boils, the steam pushes the piston upward, and then the piston closes when it is pushed to the top of the cylinder. Then, the steam in the cylinder is cooled, and the atmospheric pressure pushes the piston down. Through this cycle of heating and cooling, the piston is pushed up and down. Although Papen's steam engine is primitive, it is of epoch-making significance in terms of its cylinder and piston. Of course, this kind of steam engine can't be used in industrial production and has little practical value. Newcomen practical steam engine. Newcomen is a hardware dealer in Britain. He is very familiar with the situation of mines and knows that a large number of mine owners in Europe are very upset because they can't pump out the water in the mines. He is determined to solve the problem with a steam engine. Newcomen spent 10 years researching and experimenting, and finally made a new steam engine in 17 12. The working principle of newcomen steam engine is that the steam engine is equipped with 1 boiler besides cylinder and piston. There is no valve in the cylinder. When the valve is opened, the steam from the boiler fills the cylinder under the piston, and the steam pushes the piston to move. When the piston reaches the apex, the steam valve closes and the other valve opens, spraying cold water to the outer wall of the cylinder. Cold water condenses steam, creating a vacuum in the cylinder, and the upper end of the piston is pressed down by atmospheric pressure. The pressure generated by the air pushing the piston reaches per square centimeter 1 kg. A piston with a big bowl generates more power than a horse. This circulating piston pushes up and down to form a power stroke. Man has finally found a machine that can work for himself. Newcomen achieved the purpose of pumping water out of the mine through this power and the matching pump valve. But this kind of steam engine has low thermal efficiency, because steam enters the cylinder for a while and is cooled by cold water for a while. It can still pump 46 meters deep mine water-therefore, this steam engine is widely used in mines. This machine is made in Germany L7/KOOC-0/5, Russia/KOOC-0/7/KOOC-0/7, Bona/KOOC-0/722, France/KOOC-0/725,/KOOC-0/8. Watt's two improvements to the steam engine. More than 60 years after the steam engine invented by newcomen was put into use, a young Englishman began to improve the steam engine. This young man named Watt Watt studied in a university in Glasgow, England. At that time, Watt accepted the task of repairing newcomen steam engine assigned by the school. In the process of repairing, Watt found that the steam engine had many shortcomings, and he immediately set about reforming it. The first improvement was completed in 1775. Watt first reformed the cylinder block of newcomen steam engine. The cylinder block frequently changes hot and cold, consuming heat energy. Watt assumes that the heating and cooling tasks are undertaken by two containers respectively, so that the working cylinder can always be kept in a high heat state. Of course, this also requires an additional condenser. Its working principle is: first, open the boiler steam valve, so that steam enters the cylinder and pushes the piston upward. When the steam pushes the piston to the top of the cylinder, close the steam valve and open the valve connected with the condenser at the same time, so that the steam pressure in the cylinder suddenly disappears and condenses, forming a vacuum in the cylinder. Air pressure will cause the piston to move down again. So as long as these two valves are alternately opened and closed, the piston will move up and down quickly. After Watt's transformation, the thermal efficiency of the steam engine was increased by three times, and the coal consumption was saved 1/4. 1769, watt obtained his new technology patent, 1775, he invented "watt steam engine". 1784 after the first improvement, after years of research, the existing problems were improved for the second time. This improvement mainly solves two problems: first, it improves the shortcoming that the piston can only move up and down in a straight line. Watt drives the crankshaft with a connecting rod, so that the linear kinetic energy of the piston is converted into circular kinetic energy. The second is to invent the earliest automatic control system in the world, which can automatically adjust the steam flow and keep the running speed of the machine constant. There is no need to rely on people to adjust the valve. The improvement of Watt was completed in 1784. Because of this improvement, the steam engine was widely used in industrial production, and because Watt made outstanding contributions to the transformation of the steam engine, it was later thought that Watt invented the steam engine, and the time of invention was also identified as 1775 or 1784. The wide application of steam engine Watt's steam engine ignited the fuse of "industrial revolution". It soon provided a powerful power machine in the industrial production of the United States, France, Hungary, Germany and other countries, which made the production of human society advance by leaps and bounds. As Marx said, the invention of the steam engine changed the whole world in a short time, from 1786 to 1800. Time comparison It took 72 years from 17 12 when newcomen manufactured the first steam engine for practical production to 1784 when Watt completed the second transformation of the steam engine. China in these 72 years is far away from Kangxi (1661-1year) and Yongzheng (1722-1734) in the east and Qianlong (/) in the early Qing dynasty. By the end of Qianlong period, China's total economic output ranked first in the world, with a population of13 and a long-term growth in foreign trade. However, due to various reasons, China was at a loss about the industrial revolution that took place in the world at that time. Neither participated in it, nor shared the technological achievements, so that China's science and technology gradually declined in the next century. Finally, one day, the western powers with advanced production tools, relying on their ships and guns, opened the door of China and humiliated and plundered the people of China.