**6. Appendix**

Functions (,) *F xc <sup>n</sup>* and , (,,) *I xcd n m* and their Laplace transforms are given as described below (x ≥ 0, *c d*, , and n, m = 1, 2, 3,....). For x < 0, both functions are equal to zero.

$$F\_n(\mathbf{x}, \mathbf{c}) = \frac{\mathbf{x}^{n-1}}{(n-1)!} \cdot \exp(-\mathbf{c} \cdot \mathbf{x}) \Leftrightarrow \frac{1}{\left(\mathbf{s} + \mathbf{c}\right)^n} \tag{A.1}$$

$$I\_{n,m}(\mathbf{x}, \mathbf{c}, d) = \sum\_{j=1}^{n} \binom{m+j-1}{j} \cdot d^j \cdot F\_{n+m+j}(\mathbf{x}, \mathbf{c}, d) \Leftrightarrow \frac{1}{\left(s+c\right)^n \cdot \left(s+c-d\right)^m} \tag{A.2}$$

Some additional details about these functions can be found in an earlier paper (Gvozdenac, 1986).

## **7. Nomenclature**




**3** 

*Japan* 

**Self-Heat Recuperation:** 

**Theory and Applications** 

Muhammad Aziz2 and Atsushi Tsutsumi1

*1Collaborative Research Center for Energy Engineering, Institute of Industrial Science,* 

Since the 1970s, energy saving has contributed to various elements of societies around the world for economic reasons. Recently, energy saving technology has attracted increased interest in many countries as a means to suppress global warming and to reduce the use of fossil fuels. The combustion of fossil fuels for heating produces a large amount of carbon dioxide (CO2), which is the main contributor to global greenhouse gas effects (Eastop & Croft 1990, Kemp 2007). Thus, the reduction of energy consumption for heating is a very important issue. To date, to reduce energy consumption, heat recovery technology such as pinch technology, which exchanges heat between the hot and cold streams in a process, has been applied to thermal processes (Linnhoff et al. 1979, Cerda et al. 1983, Linnhoff et al. 1983, Linnhoff 1993, Linnhoff & Eastwood 1997, Ebrahim & Kawari 2000). A simple example of this technology is the application of a feed-effluent heat exchanger in thermal processes, wherein heat is exchanged between feed (cold) and effluent (hot) streams to recirculate the self-heat of the stream (Seider et al. 2004). To exchange the heat, an additional heat source may be required, depending on the available temperature difference between two streams for heat exchange. The additional heat may be provided by the combustion of fossil fuels, leading to exergy destruction during heat production (Som & Datta 2008). In addition, many energy saving technologies recently developed are only considered on the basis of the first law of thermodynamics, i.e. energy conservation. Hence, process design methods based on

Simultaneously, many researchers have paid attention to the analysis of process exergy and irreversibility through consideration of the second law of thermodynamics. However, many of these investigations show only the calculation results of exergy analysis and the possibility of the energy savings of some processes, and few clearly describe methods for reducing the energy consumption of processes (Lampinen & Heillinen 1995, Chengqin et al 2002, Grubbström 2007). To reduce exergy reduction, a heat pump has been applied to thermal processes, in which the ambient heat or the process waste heat is generally pumped to heat the process stream by using working fluid compression. Although it is well-known that a heat pump can reduce energy consumption and exergy destruction in a process, the

these technologies are distinguished by cascading heat utilization.

**1. Introduction** 

*2Advanced Energy Systems for Sustainability, Solution Research Laboratory* 

Yasuki Kansha1, Akira Kishimoto1,

*The University of Tokyo* 

*Tokyo Institute of Technology* 

Subscripts:

1 fluid 1 2 fluid 2 w wall

#### **8. Acknowledgment**

This work was performed as a part of the research supported by Provincial Secretariat for Science and Technological Development of Autonomous Province of Vojvodina.

#### **9. References**


Gvozdenac, D. D. (1987). *Analytical solution of transient response of gas-to-gas parallel and counterflow heat exchangers*, ASME J. Heat Transfer, 109, pp 848-855


Gvozdenac, D. D. (1990). *Transient response of the parallel flow heat exchanger with finite wall capacitance*, Ing. Arch., 60, pp 481 -490

Gvozdenac, D. D. (1991). *Dynamic response of the crossflow heat exchanger with finite wall capacitance*, Wärme- und Stoffübertragung, 26, pp 207-212

