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When we want to heat a stream of liquid by Steam, we usually keep removing the condensate from the surface of the tube.

When we want to heat a stream of liquid by Steam, we usually keep removing the condensate from the surface of the tube. Correct Answer True

It is best suited when we keep removing condensate from the tube surface as film condensation decreases the heat transfer coefficient and removing it supports drop-wise condensation.

Related Questions

In a surface condenser, the water flowing through a series of tubes at the rate of 200 kg/hr is heated from 15 degree Celsius to 75 degree Celsius. The steam condenses on the outside surface of tubes at atmospheric pressure and the overall heat transfer coefficient is estimated at 860 k J/m2 hr degree. Find the effectiveness of the heat exchanger. At the condensing pressure, stream has a saturation temperature 0f 100 degree Celsius and the latent heat of vaporization is 2160 k J/kg. Further, the steam is initially just saturated and the condensate leaves the exchanger without sub-cooling i.e. only latent heat of condensing steam is transferred to the water. Take specific heat of water as 4 k J/kg K
In a surface condenser, the water flowing through a series of tubes at the rate of 200 kg/hr is heated from 15 degree Celsius to 75 degree Celsius. The steam condenses on the outside surface of tubes at atmospheric pressure and the overall heat transfer coefficient is estimated at 860 k J/m2 hr degree. Find the number of transfer units of the heat exchanger. At the condensing pressure, stream has saturation temperature 0f 100 degree Celsius and the latent heat of vaporization is 2160 k J/kg. Further, the steam is initially just saturated and the condensate leaves the exchanger without sub-cooling i.e. only latent heat of condensing steam is transferred to water. Take specific heat of water as 4 k J/kg K
The fresh feed to an ammonia synthesis reactor contains nitrogen, hydrogen and 2.0 mole per cent inerts. The molar ratio of H2:N2 is 3:1. The product stream consists of pure ammonia. Since conversion in the reactor is only 15%, a recycle stream is used and in order to avoid build-up of inerts, a purge stream is withdrawn. The rate of purge stream is adjusted to keep inert concentration in the recycle stream at 8 mole per cent. For a fresh feed rate of 100 moles/hr. Note that recycle stream contains only nitrogen, hydrogen and inerts. The N2:H2 ratio of 1:3 is maintained in every process stream, and calculate the moles of nitrogen entering the reactor and in the recycle stream?
The fresh feed to an ammonia synthesis reactor contains nitrogen, hydrogen and 2.0 mole per cent inerts. The molar ratio of H2:N2 is 3:1. The product stream consists of pure ammonia. Since conversion in the reactor is only 15%, a recycle stream is used and in order to avoid build-up of inerts, a purge stream is withdrawn. The rate of purge stream is adjusted to keep inert concentration in the recycle stream at 8 mole per cent. For a fresh feed rate of 100 moles/hr. Note that recycle stream contains only nitrogen, hydrogen and inerts. The N2:H2 ratio of 1:3 is maintained in every process stream, and calculate the number of moles, moles of inerts and moles of hydrogen in the recycle stream?
A two pass surface condenser is required to handle the exhaust from a turbine developing 15 MW with specific steam consumption of 5 kg/k W h. The quality of exhaust steam is 0.9, the condenser vacuum is 66 cm of mercury while the bar meter reads 76 cm of mercury. The condenser tubes are 28 mm inside diameter, 4 mm thick and water flows through tubes with a speed of 3 m/s and inlet temperature 20 degree Celsius. All the steam is condensed, the condensate is saturated water and temperature of cooling water at exit is 5 degree Celsius less than the condensate temperature. Assuming that overall coefficient of heat transfer is 4 k W/m2 degree, determine the mass of cooling water circulated
The fresh feed to an ammonia synthesis reactor contains nitrogen, hydrogen and 2.0 mole per cent inerts. The molar ratio of H2:N2 is 3:1. The product stream consists of pure ammonia. Since conversion in the reactor is only 15%, a recycle stream is used and in order to avoid build-up of inerts, a purge stream is withdrawn. The rate of purge stream is adjusted to keep inert concentration in the recycle stream at 8 mole per cent. For a fresh feed rate of 100 moles/hr. Note that recycle stream contains only nitrogen, hydrogen and inerts. The N2:H2 ratio of 1:3 is maintained in every process stream. Calculate the moles of ammonia produced.
When we want to heat a stream of liquid by Steam, we usually keep steam on the shell side and fluid in the tube.
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it. The first working steam­ powered vehicle was designed and most likely built by Ferdinand Verbies, a Flemish member of a Jesuit mission in China around 1672. It was a 65 cm long scale­ model toy for the Chinese Emperor, that was unable to carry a driver or a passenger. It is not known if Verbiest's model was ever built. Nicolas- Joseph Cugnot is widely credited with building the first full­ scale, self ­propelled mechanical vehicle or automobile in about 1769; he also created a steam­ powered tricycle. He constructed two steam tractors for the French Army, one of which is preserved in the French National Conservatory of Arts and Crafts. His inventions were however handicapped by problems of water supply and maintaining steam pressure. In 1801, Richard Trevithick built and demonstrated his Puffing Devil road locomotive, believed by many to be the first demonstration of a steam ­powered road vehicle. It was unable to maintain sufficient steam pressure for long periods. Sentiment against steam ­powered road vehicles led to the Locomotive Acts of 1865. In 1807 Nicephore Niepce and his brother Claude probably created the world's first internal combustion engine which they called Pyreolophore. The first full­scale, working steam ­powered tricycle was built by:
Read the passage carefully and choose the best answer to each question out of the four alternatives and click the button corresponding to it. The first working steam­ powered vehicle was designed and most likely built by Ferdinand Verbies, a Flemish member of a Jesuit mission in China around 1672. It was a 65 cm long scale­ model toy for the Chinese Emperor, that was unable to carry a driver or a passenger. It is not known if Verbiest's model was ever built. Nicolas- Joseph Cugnot is widely credited with building the first full­ scale, self ­propelled mechanical vehicle or automobile in about 1769; he also created a steam­ powered tricycle. He constructed two steam tractors for the French Army, one of which is preserved in the French National Conservatory of Arts and Crafts. His inventions were however handicapped by problems of water supply and maintaining steam pressure. In 1801, Richard Trevithick built and demonstrated his Puffing Devil road locomotive, believed by many to be the first demonstration of a steam ­powered road vehicle. It was unable to maintain sufficient steam pressure for long periods. Sentiment against steam ­powered road vehicles led to the Locomotive Acts of 1865. In 1807 Nicephore Niepce and his brother Claude probably created the world's first internal combustion engine which they called Pyreolophore. Cugnot built steam tractors for:
In a counter flow heat exchanger, water flowing through a tube of 10 cm inner diameter is heated by steam condensing on the outside of the tube. The convective film coefficient on the water and steam side are estimated to be 12000 and 20000 k J/m2 hr degree. Neglecting tube thickness and its resistance to heat flow, workout the overall heat transfer coefficient for the heat exchanger