Thermal loads

Cooling tower blowdown can be reduced by improving the energy efficiency of processes, thus reducing the thermal load on cooling towers. Alternatively, cooling water systems can be switched to air coolers, which eliminates the problem altogether. 

The insensitivity of adiabatic flame temperature to heat of combustion does not necessarily apply to the operational flame temperature, T, which is the flame temperature found in an actual furnace (remembering that this refers to some average temperature). The higher excess air requirements at higher C/H ratios coupled with greater thermal loads on longer flames generally results in markedly lower operational temperatures as the C/H ratio increases. 

Eor shifting coal-derived gas, conventional iron—chromium catalysts can be used. Because coal gas has a significantly higher concentration of carbon monoxide than is found in gas streams in conventional refineries, the catalyst must be able to withstand high thermal loads. However, potential catalyst poisons such as phenol and other hydrocarbons are not a concern in entrained-bed gasifiers. 

The variable-pitch arrangement at constant motor speed changes the pitch of the olades through a pneumatic signal from the leaving-water temperature. As the thermal load and/or the ambient wet-bulb temperature decreases, the blade pitch reduces air flow and less fan energy is required. 

The purpose of the deceleration mode is to decelerate the unloaded system inertia to near zero rpm in a specified time period. As the e-stop relay switches to the deceleration mode, the brake coil is excited from the battery source at a lower, constant value voltage, which will produce sufficient torque to achieve the rated brake continuous thermal load. The system will then decelerate under a constant torque load. 

Cross-sectionai area. The combustor cross section can be determined by dividing the volumetric flow at the combustor inlet by a reference velocity which has been selected as being appropriate for the particular turbine conditions on the basis of proven performance in a similar engine. Another basis for selecting a combustor cross section comes from correlations of thermal loading per unit cross section. Thermal loading is proportional to the primary zone air flow because fuel and air mixtures are near stoichiometric in all combustors. 

It may be noted that in this area the newly introduced nylon 46 has become of interest in auto automatic gears, gearboxes, engine differentials and the clutch area because of its exceptional ability (for a polyamide) to withstand severe mechanical and thermal loading. ... 

Next generation machines will impose inereasingly greater thermal loads on their PFCs. High thermal conductivity CFC materials may offer a solution to the high-heat loads, but further research is needed to overeome the problems noted above and to assure the place of earbon materials in future fusion power reaetors. 

The building is an industrial laundry with high thermal loads, ventilated naturally or by hybrid ventilation. The laundry cleans, among other things, hospital textiles thus, high hygienic standards are required Three different levels of internal thermal loads were assumed (60, 100, 160 W/m i for the sirnularitins. 

The study shows that in this particular case a natural ventilation system is a suitable and ecological possibility to remove the high internal thermal loads. Accurate information on the internal loads and the ventilation openings is crucial for the results of the thermal simulation. 

Breer 11., and Dorer V. Industrial buildings with high thermal loads simulation of natural ventilation. RoomVent 98 conference,. Stockholm, 1998. 

Variable flow An assembly within which the primary airflow rate is modulated and mixed with air induced from the surroundings by means of a noncontinuous running fan that provides a variable flow in response to thermal loads (also known as parallel type). 

Thermal load The heating or cooling requirements of a space due to structural gains or losses and the air infiltration and mechanical ventilation. The load produced by a process in a working environment. 

Ventilation thermal load The heating or cooling load required to compensate for thermal losses resulting from natural or mechanical ventilation. 

Upon normal solution of mechanical loading, or mechanical and thermal loading, problems, the stresses in the laminae can be deter-... 

Coal burners Type Size range (MW) Fuels Grate thermal loading (mW/m ) Bed thickness Turndown ratio Ashing system Main applications... 

Changes in circumstances will frequently require modifications to an existing cooling tower. Additional heat loads may be needed, and changes in the end process may cause the return temperature to increase, necessitating a new thermal load on the tower. Most frequently it is a requirement for an increase in hydraulics. 

In addition, dehydrogenated structures were found to cause a hypsochromic shift. Since, with the exception of neobetanin, these betacyanin degradation products were found not to be native to betalain crops, it is suggested that these peculiar structures may be used as heat indicators to assess the thermal loads of the respective products have undergone during production. 

It is noteworthy that trifluoroacetic acid was introduced as the most appropriate acidifler for column chromatography and solid phase extraction techniques, i.e., low boiling point due to its high acidity, requiring low amounts to reach the respective pH. Also, its high volatility allows easy evaporation thus minimizing the thermal load and acidification during concentration. 

A nitrobenzene/nitrogen tetroxide mixture used to be used as an explosive liquid. However, it is not still used due to its high sensitivity to thermal load. 

Benzoquinone moistened by water gives rise to an important thermal load. A DTA showed that the exothermic peak is reached at 40-50 C and the compound decomposes at a temperature starting at 60-70°C. When a bottle of benzoquinone is exposed to sunlight, its temperature reaches 50-60°C rapidly. 

A method of thermodynamic analysis for site steam systems will next be developed to allow the thermal loads and levels on a complete site to be studied. For this, a temperature-enthalpy picture for the whole site is needed, analogous to the grand composite curve for an individual process, as developed in Chapter 16. There are two ways in which such curves can be developed. The first relates to a new design situation. 

Site composite curves can be used to represent the site heating and cooling requirements thermodynamically. This allows the analysis of thermal loads and levels on site. Using the models for steam turbines and gas turbines allows cogeneration targets for the site to be established. Steam levels can be optimized to minimize fuel consumption or maximize cogeneration. A cost trade-off needs to be carried out in order to establish the optimum trade-off between fuel requirements and cogeneration. 

Borishansky, V. M., 1961, Allowing for the Influence of Pressure on the Heat Transfer and Critical Thermal Loads during Boiling in Accordance with the Theory of Thermodynamic Similarity, Voprosy Teplootdachi i gidravliki Dvukhfaznykh Sred, Gosenergoizdet, Moscow. (2)... 

Kutateladze, S. S, and L. L. Schneiderman, 1953, Experimental Study of Influence of Temperature of Liquid on the Change in the Rate of Boiling, USAEC Rep. tr-3405, 95-100, Washington, DC. (2) Labuntsov, D. A., 1961, Critical Thermal Loads in Forced Motion of Water Which is Heated to a Temperature below the Saturation Temperature, Sov. J. Atomic Energy (English transl.) 70 516-518.(5)... 

Some prototype components are already under development. One of them is a ramp for the intake of the hypersonic propulsion system. This rather complex structure with dimensions of about 500 x 600 x 80 mm (in one piece) is planned to be tested under simulated thermal loads in early 1993. 

In many cases the broader distribution can be attributed to the amorphous (or soft) phase. Even higher significance of the assignment can be achieved if the material is studied in time-resolved SAXS experiments during processing (under thermal load, mechanical load). Thus it is not always necessary to resort to secondary methods112 in order to resolve the ambiguity inherent to Babinet s theorem. 

Capacitance measurements are quite simple. A typical drawback is the need of coaxial cables that introduce a thermal load which is not negligible in low-power refrigerators. On the other hand, capacitance bridges null the cable capacitance. Multiplexing is more difficult than for resistance thermometers. In principle, capacitors have low loss due to Joule heating. This is not always true losses can be important, especially at very low temperatures. Dielectric constant thermometers have a high sensitivity capacitance differences of the order of 10-19F can be measured. 

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