scholarly journals Thermodynamics and dynamics of a monoatomic glass former. Constant pressure and constant volume behavior

2008 ◽  
Vol 128 (14) ◽  
pp. 144505 ◽  
Author(s):  
Vitaliy Kapko ◽  
Dmitry V. Matyushov ◽  
C. Austen Angell
Keyword(s):  
Constant Pressure ◽  
Constant Volume ◽  
Thermodynamics And Dynamics

scholarly journals On the temperature variation of the specific heats of hydrogen and nitrogen

1930 ◽  
Vol 126 (801) ◽  
pp. 204-212 ◽  
Keyword(s):  
Kinetic Theory ◽  
Temperature Variation ◽  
Characteristic Equation ◽  
Constant Pressure ◽  
Ideal Gas ◽  
Constant Volume ◽  
Specific Heats

The energy of a gram molecule of an ideal gas can be calculated from the kinetic theory. From this, by the application of the Maxwell-Boltzmann hypothesis, the molecular specific heats at constant volume, S v , of ideal monatomic and diatomic gases are deduced to be 3R /2 and 5R/2 respectively at all temperatures. R is the gas constant per gram molecule = 1⋅985 gm. cal./° C. The corresponding molecular specific heats at constant pressure, S p , can be obtained by the addition of R. In the case of real gases, which obey some form of characteristic equation other than P. V = R. T, it can be shown from thermodynamical considera­tions that the value of S p depends upon the pressure, but as the term involving the pressure also includes the temperature, S p is not independent of the tempera­ture but it increases in value as the temperature is reduced. Assuming the characteristic equation proposed by Callendar, i. e. , v - b ­­= RT/ p - c (where b is the co-volume, c is the coaggregation volume which is a function of the temperature of the form c = c 0 (T 0 /T) n , n being dependent on the nature of the gas), it is easy to show from the relation (∂S p /∂ р ) T = -T(∂ 2 ν /∂Τ 2 ) р , hat S p = S p 0 + n (n + 1) cp /T; and, by combining this with S p – S v = T(∂ p /∂Τ) v (∂ v /∂Τ) p = R(1 + ncp /RT) 2 , the corresponding values of S v can be obtained.

Specific Heat of Natural Rubber

1951 ◽  
Vol 24 (2) ◽  
pp. 285-289 ◽  
Author(s):  
Hiroshi Ichimura
Keyword(s):  
Low Temperature ◽  
Natural Rubber ◽  
Specific Heat ◽  
Constant Pressure ◽  
Constant Volume ◽  
Theoretical Considerations

Abstract The constant volume specific heat of natural rubber is calculated from the constant pressure specific heat, which is measured experimentally, and it is shown that the low temperature part is expressed by a combination of the Debye and Einstein formulas. Some theoretical considerations on the transition phenomena at 200° K are included.

FALSIFICATIONS OF POISSON ADIABATE, HUGONIO ADIABATE, LAPLACE SOUND SPEEDS. MODERNIZATION OF FOUNDATIONS OF THERMODYNAMICS

2020 ◽  
Vol 5 (333) ◽  
pp. 58-67
Author(s):  
K.B. Jakupov ◽  
Keyword(s):  
Shock Wave ◽  
Heat Capacity ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Speed Of Sound ◽  
Constant Pressure ◽  
Energy Balance Equation ◽  
Ideal Gas ◽  
Constant Volume ◽  
Capacity Coefficient

The inequality of the universal gas constant of the difference in the heat capacity of a gas at constant pressure with the heat capacity of a gas at a constant volume is proved. The falsifications of using the heat capacity of a gas at constant pressure, false enthalpy, Poisson adiabat, Laplace sound speed, Hugoniot adiabat, based on the use of the false equality of the universal gas constant difference in the heat capacity of a gas at constant pressure with the heat capacity of a gas at a constant volume, have been established. The dependence of pressure on temperature in an adiabatic gas with heat capacity at constant volume has been established. On the basis of the heat capacity of a gas at a constant volume, new formulas are derived: the adiabats of an ideal gas, the speed of sound, and the adiabats on a shock wave. The variability of pressure in the field of gravity is proved and it is indicated that the use of the specific coefficient of ideal gas at constant pressure in gas-dynamic formulas is pointless. It is shown that the false “basic formula of thermodynamics” implies the falseness of the equation with the specific heat capacity at constant pressure. New formulas are given for the adiabat of an ideal gas, adiabat on a shock wave, and the speed of sound, which, in principle, do not contain the coefficient of the specific heat capacity of a gas at constant pressure. It is shown that the well-known equation of heat conductivity with the gas heat capacity coefficient at constant pressure contradicts the basic energy balance equation with the gas heat capacity coefficient at constant volume.

scholarly journals Constant Pressure and Constant Volume Direct Shear Tests on Reinforced Sand

2000 ◽  
Vol 40 (4) ◽  
pp. 1-17 ◽  
Author(s):  
Jin-Ying Qiu ◽  
Fumio Tatsuoka ◽  
Taro Uchimura
Keyword(s):  
Constant Pressure ◽  
Constant Volume ◽  
Direct Shear ◽  
Shear Tests ◽  
Reinforced Sand ◽  
Direct Shear Tests

scholarly journals The Constant Volume Gas Turbine Cycle According to Karavodine

1982 ◽  
Author(s):  
H. Vandermeulen
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Constant Pressure ◽  
Constant Volume ◽  
Theory And Practice ◽  
Pressure Cycle ◽  
Basic Distinction ◽  
Overall Performance ◽  
The One ◽  
Gas Turbine Cycle

The basic distinction between the constant volume cycle and the well known constant pressure cycle for gas turbines is the method of heat supply, which necessitates a system of combustion chamber valves to contain the fluid. The object of the proposed cycle analysis, which is mainly based on the fundamental laws of mass and energy, will consider a solution for the discrepancies between the former theory and practice of constant volume gas turbines. The overall performance characteristics which emerge from this analysis show the distinct superiority of the one-valve Karavodine cycle. Evaluation by experiment for this cycle variant shows, however, besides a refinement of the model, a marginal superiority in performance for the Brayton gas turbine at low pressure ratios. Any application could probably be justified by incorporating it in Brayton turbines to diminish starting power and to improve part load performance.

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