Heat capacity cooling

Hence, it is necessary to correct the temperature change observed to the value it would have been if there was no leak. This is achieved by measuring the temperature of the calorimeter for a time period both before and after the process and applying Newton s law of cooling. This correction can be reduced by using the teclmique of adiabatic calorimetry, where the temperature of the jacket is kept at the same temperature as the calorimeter as a temperature change occurs. This teclmique requires more elaborate temperature control and it is prunarily used in accurate heat capacity measurements at low temperatures. 

Fig. 3. Temperature—enthalpy representation of stream where A represents a pure component that is condensiag, eg, steam B and C represent streams having constant heat capacity, that are to be heated or cooled, respectively and D represents a multicomponent mixture that changes phase as it is...

Suspension Polymerization. In this process the organic reaction mass is dispersed in the form of droplets 0.01—1 mm in diameter in a continuous aqueous phase. Each droplet is a tiny bulk reactor. Heat is readily transferred from the droplets to the water, which has a large heat capacity and a low viscosity, faciUtating heat removal through a cooling jacket. 

Pump is operated Match pump capacity to the service at a fraction of, Install minimum flow recirculation line to heat capacity. Possihil- ensure adequate cooling of the pump ities of excessive internal interlock to shutdown pump on mini-recirculation, fre- indication quent seal and Implement procedural controls to avoid operat-bearing failure ing at too low a flow resulting in loss of, Provide deadhead protection containment. CCPS G-23 CCPS G-29... 

In order to avoid the need to measure velocity head, the loop piping must be sized to have a velocity pressure less than 5% of the static pressure. Flow conditions at the required overload capacity should be checked for critical pressure drop to ensure that valves are adequately sized. For ease of control, the loop gas cooler is usually placed downstream of the discharge throttle valve. Care should be taken to check that choke flow will not occur in the cooler tubes. Another cause of concern is cooler heat capacity and/or cooling water approach temperature. A check of these items, especially with regard to expected ambient condi-... 

Given a number Nh of process hot streams (to be cooled) and a number Nq of process cold streams (to be heated), it is desired to synthesize a cost effective network of heat exchangers which can transfer heat from the hot streams to the cold streams. Given also are the heat capacity (flowrate x specific heat) of each process hot stream, FCp u, its supply (inlet) temperature, and target (outlet) temper-... 

Another technique that can be used to account for the presence of liquids is to assume that the water and oil in the stream pass through the choke with no phase change or loss of temperature. The gas is assumed to cool to a temperature given in Figure 4-8. The heat capacity of the liquids is then used to heat the gas to determine a new equilibrium temperature. 

Air conditioning systems have been traditionally compared and rated by cooling and/or heating capacity and, more recently, energy efficiency. Capacity is expressed in British thermal units per hour (Bttili) or in watts. Energy efficiency is expressed as the operat-... 

In the summer, the COP of an air-to-air heat pump decreases as the outdoor temperature rises, reducing the cooling capacity. Normally the thermal needs of the building are met since it is common practice to size a heat pump so that it will deliver adequate cooling capacity in all but the most extreme summer conditions. The winter heating capacity of the system is then determined by this tradeoff, and if the heating capacity is inadequate, supplemental electric or fossil fuel heat is required. 

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