The Infrared Opacity of Hot Water Vapor

1967 ◽  
Vol 14 ◽  
pp. 171 ◽  
Author(s):  
Jason, Jr. Auman
Keyword(s):  
2020 ◽  
Vol 161 ◽  
pp. 01056
Author(s):  
Magomed Akhmetov ◽  
Amiiat Demirova ◽  
Vladimir Piniaskin ◽  
R.A. Rakhmanova

Perfection of technological processes, both in preliminary preparation of raw materials and during the final mandatory step of pasteurization, plays a key role in ensuring the quality of finished products, which is important in the production of canned dietary products. The aim of the research was to develop a more efficient way of blanching raw materials with its hardware and soft pasteurization modes, which will allow the production of high quality and competitive compotes for functional nutrition. We have developed and proposed a method of pulse-steam blanching of raw materials directly in glass jars with saturated water vapor, instead of the traditional method using hot water. The essence of the method is as follows. Fruits stacked in jars are pulse heated for 100–160 seconds (depending on the volume of the container) with saturated water vapor with temperature of 105–110 °C, and then fed into jars with cycles of 10 and 10 seconds respectively. The use of pulsed supply of saturated water vapor contributes to achieving more even heating of the fruit, which are characterized by a relatively large internal thermal resistance, causing overheating of the surface layers, and also provides an increase in the temperature of the product, which allows to pour into the jars syrup at relatively high temperature (97–98 °C), while the traditional technology accounts for the temperature of only 80–85 °C. Implementation of this method ensures the temperature level of the product entering the pasteurization stage being 78–80 °C, as opposed to the traditional method, where the temperature of the product is 45–48 °C. After that, the jars will be filled with syrup with a temperature of 97–98 °C, sealed and sent for pasteurization on accelerated modes. To implement the new method of blanching, the design of the device for pulse-steam blanching of fruits in glass jars has been developed. New thermal sterilization regimes have been developed, taking into account the increased temperature of the product after sealing and improved technology for the production of pear compote. The results of physical and chemical testing confirm the high quality of the finished product.


Author(s):  
Farnosh Dalili ◽  
Mats Westermark

This paper examines the performance of gas turbine cycles operating with a mixture of air and water vapor. Special attention is paid to the humidification tower, where the water vapor is added to the air. The experiments in this study have been carried out in the first evaporative gas turbine pilot plant located at Lund Institute of Technology in the southern part of Sweden. This pilot plant is based on a Volvo VT600 gas turbine with a design load of 600 kW. The compressor pressure is just above 8 bars and the intake air-flow is 3.4 kg/s. Roughly 70 percent of the compressed air is humidified in the humidification tower, which is the only humidifying device. The tower diameter is 0.7 m and the total flexible packing height is 0.9 m of a stainless steel structured packing with a specific surface area of 240 m2/m3. The number of mass transfer units in the humidifier was experimentally determined to about 3 for a packing height of 0.45 m. The height of a transfer unit from the literature data for the packing is predicted to be 0.24 m. With a packing height of 0.45 m, only about 2 transfer units are expected from the packing. However, the droplet zones above and below the packing contribute about 1 transfer unit. Thus, it is concluded that the mass transfer performance of the packing is adequately predicted by literature data. Equations are provided to adjust the height of a transfer unit for other pressures and temperatures. For full-scale plants operating at higher pressures and temperatures it is suggested that the high quality exhaust heat, (temperatures above the boiling point) is recovered in a boiler and injected as steam. The remaining part of the exhaust heat, (temperatures below the boiling point) is used to produce hot water for a relatively small humidification tower using only a portion of the compressed air flow.


2005 ◽  
Vol 140 (4) ◽  
pp. 319-331 ◽  
Author(s):  
P. Chelin ◽  
C. Camy-Peyret ◽  
V. Pina ◽  
P. Alkhoury ◽  
D. Davidenko

2002 ◽  
Vol 206 ◽  
pp. 314-317
Author(s):  
Tarja Liljeström ◽  
Anders Winnberg ◽  
Roy Booth

The SEST telescope has been used for a submillimeter water maser survey toward late-type stars. Six new 321 GHz water masers were detected. These, as well as the earlier reported sources, VY CMa and o Cet, were also observed in the vibrationally excited water maser line at 96 GHz. However, only VY CMa and o Cet showed the 96 GHz emission. The line velocity of o Cet is blueshifted, suggesting that the hot water vapor at 96 GHz takes part in the pulsation-shock motion of the Mira variable.


Author(s):  
Ahmed Hamza H. Ali

In this study, a detailed modeling of the heat and mass transfer processes inside a plate-and-frame absorber with hydrophobic microporous membrane contactor at aqueous solution-water vapor interface as a part of a chiller model is developed. The absorber is a component of a 5 kW cooling capacity single effect lithium bromide-water absorption chiller with a hot water thermally driven generator, a water-cooled absorber, and a condenser. The model is used to investigate the performance of the absorber in case the chiller operates at different values of the inlet driving hot water and cooling water (coolant) temperatures. The results clearly indicate that for the same cooling capacity of the chiller and compared with the performance at the design point value, increasing the inlet driving hot water temperature results in an increase in the required absorber size and consequently a decrease in the absorber performance, while decreasing the cooling water (coolant) inlet temperature leads to slight decreases in the required absorber size and consequently an increase in the absorber performance. The effect is prominent and can be used to decrease the absorber size for chillers work in places where the option of lower inlet coolant temperature is available with normal driving hot water temperature.


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