Heat capacity flow rate

To illustrate the application of model PI for the calculation of the minimum utility cost, we will consider the example used in section 8.3.1.2, with data provided in Table 8.1 of that section. This example features constant flow rate heat capacities, one hot and one cold utility being steam and cooling water, respectively. Here, we assume C = Cj = 1, that is we meet the minimum utility consumption. 

F is the flow rate heat capacity of cold stream j,... 

In other nonisothermal cases, the parameters have significant influence on the temperature profile, especially the parameters flow rate, heat capacity, heat transfer coefficients, and heat transfer area. 

C Flow stream heat capacity rate with a subscript cot h, rhCp, W/°C, Btu/hr °F... 

For a zero-order chemical reaction (including a term for the contribution to the heat flow Ifom heat capacity), the rate of the reaction is dependent only on temperature. Thus, it produces heat at a rate given by some function of temperature h(T). Taking the heating programme given in Eq. (6)... 

Modulated DSC (MDSC ) is a patented technique from TA Instruments, New Castle, DE. In MDSC, a controlled, single-frequency sinusoidal temperature oscillation is overlaid on the linear temperature ramp. This produces a corresponding oscillatory heat flow (i.e., rate of heat transfer) proportional to physical properties of the sample. Deconvolution of the oscillatory temperature and heat flow lead to the separation of the overall heat flow into heat capacity and kinetic components. 

Reactor heat carrier. Also as pointed out in Sec. 2.6, if adiabatic operation is not possible and it is not possible to control temperature by direct heat transfer, then an inert material can be introduced to the reactor to increase its heat capacity flow rate (i.e., product of mass flow rate and specific heat capacity) and to reduce... 

Consider the simple flowsheet shown in Fig. 6.2. Flow rates, temperatures, and heat duties for each stream are shown. Two of the streams in Fig. 6.2 are sources of heat (hot streams) and two are sinks for heat (cold streams). Assuming that heat capacities are constant, the hot and cold streams can be extracted as given in Table 6.2. Note that the heat capacities CP are total heat capacities and... 

Stream Type Supply temp. Ts CO Target temp. Tr (°C) AH (MW) Heat capacity flow rate CP (MW°C )... 

The Ft correction factor is usually correlated in terms of two dimensionless ratios, the ratio of the two heat capacity flow rates R and the thermal effectiveness P of the exchanger ... 

Stream Supply - temperature (°C) Target temperature (°C) J. Heat capacity flow rate (MW°C b... 

The heat capacity of a gas at constant pressure is nonually detenuined in a flow calorimeter. The temperature rise is detenuined for a known power supplied to a gas flowing at a known rate. For gases at pressures greater than about 5 MPa Magee et al [13] have recently described a twin-bomb adiabatic calorimeter to measure Cy. 

Alternative representations of stream temperature and energy have been proposed. Perhaps the best known is the heat-content diagram, which represents each stream as an area on a graph (3) where the vertical scale is temperature, and the horizontal is heat capacity times flow rate. Sometimes this latter quantity is called capacity rate. The stream area, ie, capacity rate times temperature change, represents the enthalpy change of the stream. 

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