Contents 2 Specific Heat

The process is controlled by many operating parameters, such as (1) intrinsic parameters like shape and size of the raw material, initial water content, specific heat, thermal conductivity, effective diffusivity, etc. (2) operating process parameters like P, T, f, P, T, and T (3) kinetic parameters like pressure drop rate (APa/At) = (P - P )IAt and temperature... 

Specific gravity is the most critical of the characteristics in Table 3. It is governed by ash content of the material, is the primary deterrninant of bulk density, along with particle size and shape, and is related to specific heat and other thermal properties. Specific gravity governs the porosity or fractional void volume of the waste material, ie. 

Operational Characteristics. Oxygen generation from chlorate candles is exothermic and management of the heat released is a function of design of the total unit iato which the candle is iacorporated. Because of the low heat content of the evolved gas, the gas exit temperature usually is less than ca 93°C. Some of the heat is taken up within the candle mass by specific heat or heat of fusion of the sodium chloride. The reacted candle mass continues to evolve heat after reaction ends. The heat release duting reaction is primarily a function of the fuel type and content, but averages 3.7 MJ/m (100 Btu/fT) of evolved oxygen at STP for 4—8 wt % iron compositions. 

Progressive chlorination of a hydrocarbon molecule yields a succession of Hquids and/or soHds of increasing nonflammability, density, and viscosity, as well as improved solubiUty for a large number of inorganic and organic materials. Other physical properties such as specific heat, dielectric constant, and water solubihty decrease with increasing chlorine content. 

The relationships between specific heat and water content and between specific heat and ash content are hnear. Given the specific heat on a dry, ash-free basis, it can be corrected to an as-received basis. The specific heat and enthalpy of coal to 1366 K (2000°F) are given in Coal Conversion Systems Technical Data Book (part lA, U.S. Dept, of Energy, 1984). 

The hydrogen content, heat of combustion, specific heat, and thermal conductivity data herein were abstracted from Bureau of Standards MisceUaneous Pubhcation 97, Thermal Propei tie.s of Petroleum Products. These data are widely used, although other correlations have appeared, notably that by Linden and Othmer Chem. Eng. 54[4, 5], April and May, 1947). 

Phi-factor, (() A correction factor that is based on the ratio of the total heat capacity (mass x specific heat) of a vessel and the total heat capacity of the vessel contents. 

Moisture-transport simulation includes transport as well as storage phenomena, quite similar to the thermal dynamic analysis, where heat transfer and heat storage in the building elements are modeled. The moisture content in the building construction can influence the thermal behavior, because material properties like conductance or specific heat depend on moisture content. In thermal building-dynamics simulation codes, however, these... 

These techniques help in providing the following information specific heat, enthalpy changes, heat of transformation, crystallinity, melting behavior, evaporation, sublimation, glass transition, thermal decomposition, depolymerization, thermal stability, content analysis, chemical reactions/polymerization linear expansion, coefficient, and Young s modulus, etc. 

C = total weight of contents when full (kg (lbs)), h = mean specific heat of fuel oil,... 

Calculate the cubic contents of each room and, using the appropriate air change rate, the amount of heat required to warm the air to the desired temperature by multiplying the volume of air by the difference between the inside and outside temperatures and the specific heat of air. 

In salt brines, the water maybe considered as the heat transfer medium, since the specific heat capacity of the salt content is low (see Figure 12.3). The specific heat capacityofthe brine will therefore... 

The experimental data show that the magnitude of the heat capacity (or similarly of the specific heat) under adiabatic conditions decreases regularly with the increase of filler content. This phenomenon was explained by the fact that the macromolecules, appertaining to the mesophase layers, are totally or partly excluded to participate in the cooperative process, taking place in the glass-transition zone, due to their interactions with the surfaces of the solid inclusions. 

Fig. 14. The variation of the specific heat jumps at glass-transition temperatures of elacc-epoxy composites, versus the fiber volume content, uf. The values for the factor X and the mesophase, (uj and matrix, (nm) volume fractions, versus uf, as derived from the values of the respective AC, s are also plotted...

A jacketed reaction vessel containing 0.25 nv1 of liquid of specific gravity 0.9 and specific heat 3.3 kJ/kg K is heated by means of steam fed to a jacket on the walls. The contents of the tank are agitated by a stirrer rotating at 3 Hz. The heat transfer area is 2.5 nr ami the steam temperature is 380 K. The outside film heat transfer coefficient is 1.7 kW/m2 K and the 10 mm thick wall of the tank has a thermal conductivity of 6.0 W/m K... 

An open cylindrical tank 500 mm diameter and I m deep is three quarters filled with a liquid ol density 980 kg/mJ and of specific heat capacity 3 kj/kg K. If the heat transfer coefficient from the cylindrical walls and the base of the tank is 10 W/m2 K and front the surface is 20 W/m3 K, what area of heating coil, fed with steam at 383 K. is required to heat the contents from 288 K to 368 K in a half hour The overall heat transfer coefficient for the coil may be taken as 100 W/m2 K, the surroundings we at 288 K and the heal capacity of the tank itself may be neglected. 

Three different principles govern the design of bench-scale calorimetric units heat flow, heat balance, and power consumption. The RC1 [184], for example, is based on the heat-flow principle, by measuring the temperature difference between the reaction mixture and the heat transfer fluid in the reactor jacket. In order to determine the heat release rate, the heat transfer coefficient and area must be known. The Contalab [185], as originally marketed by Contraves, is based on the heat balance principle, by measuring the difference between the temperature of the heat transfer fluid at the jacket inlet and the outlet. Knowledge of the characteristics of the heat transfer fluid, such as mass flow rates and the specific heat, is required. ThermoMetric instruments, such as the CPA [188], are designed on the power compensation principle (i.e., the supply or removal of heat to or from the reactor vessel to maintain reactor contents at a prescribed temperature is measured). 

The adiabatic temperature rise can be calculated from the total heat effect and the specific heat of the reactor contents. Both parameters can, for example, be determined by using appropriate procedures for the Mettler-Toledo RC1 or Contalab. The adiabatic temperature is calculated by ... 

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