The Temperature-entropy Diagram |
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actual adiabatic expansion adiabatic process admission ammonia amount assumed Atkinson cycle atmospheric back pressure boiler Carnot cycle cent clearance steam combustion compressor condition constant pressure curve constant volume curve cooling corresponding cut-off cylinder feed cylinder walls decrease determined Diesel cycle dry steam engine entropy equal equation Ericsson cycle exhaust external fluid friction loss gas-engine gases heat received heat rejected Hence ideal increase indicator card indicator-card internal energy intrinsic energy irreversible isentropic isodynamic isothermal jacket kinetic energy liquid loge maximum method mixture motor nozzle obtained Otto cycle p₁ P₂ perature perfect gas pipe piston pound of steam pv-plane radiation Rankine cycle refrigerating refrigerative represents the heat reversible saturated steam saturated vapor specific heat specific volume stroke substance superheat superheated steam T₁ T₂ tempera temperature TEMPERATURE-ENTROPY DIAGRAM thermal efficiency throttling To-diagram To-plane To-projection total heat ture utilized valve
Popular passages
Page xv - Every physical or chemical process in nature takes place in such a way as to increase the sum of the entropies of all the bodies taking any part- in the process. In the limit, ie for reversible processes, the sum of the entropies remains unchanged.
Page 389 - The logarithm of a number is the exponent of the power to which it is necessary to raise a fixed number, in order to produce the first number.
Page xiv - Since there exists in nature no process entirely free from friction or heat-conduction, all processes which actually take place in nature, if the second law be correct, are in reality irreversible; reversible processes form only an ideal limiting case. They are, however, of considerable importance for theoretical demonstration and for application to states of equilibrium.
Page 139 - ... that the total pressure of the mixture is equal to the sum of the pressures that each gas would have exerted if present by itself in the container.
Page 97 - It is impossible, by means of inanimate material agency, to derive mechanical effect from any portion of matter by cooling it below the temperature of the coldest of the surrounding objects.
Page xii - Entropy is then a quantity which, when multiplied by the lowest available temperature, gives the incurred waste.
Page xiii - A process which can in no way be completely reversed is termed irreversible, all other processes reversible. That a process may be irreversible, it is not sufficient that it cannot be directly reversed. This is the case with many mechanical processes which are not irreversible.
Page 213 - The standard engine of comparison is therefore a perfect air-gaa engine operated between the same maximum and minimum volumes as the actual engine, receiving the same total amount of heat per cycle, but without jacket or radiation loss, and starting from one atmosphere and the selected initial temperature of 139° F. Its efficiency is the same as that of a Carnot engine working through, the temperature-range Tt — Tz or Tc — T0.
Page xiv - The (above) integral . . . has been called by Clausius the entropy of the body in state 2, referred to state 1 as the zero state. The entropy of a body in a given state, like the internal energy, is completely determined up to an additive constant, whose value depends on the zero state.
Page 213 - The efficiency is given by a very simple expression, depending only on the dimensions of the cylinder and independent of the heat-supply or the maximum temperature. If the heat-supply is increased by using a richer charge, the work done is increased, but not the efficiency. The pressure-volume or temperature-entropy diagram of the standard cycle can be drawn on the assumptions just stated, which, in the opinion of the Committee, do not essentially differ from those in actual engines.