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Fia. 5.11. Effect of the deud-spnee ratio X oil cycle power The figure shows the effect on the non-dimensional power parameter P/</)ma,V-,) of variation in the dead-space ratio X, with constant values of r. k. and ir. The dead space is the porous volume nf the rcgcneraloi an<l other heal exchangers, connecting ducts, and the clearance volumes m the expansion and compression spaces. Increase in the dead volume decreases the ratio of maximum volume to minimum volume which decreases the range of the pressure exclusion, thus causinp a decrease in the cycle powei The dead space must he minimized for high cycle power.

Fia. 5.11. Effect of the deud-spnee ratio X oil cycle power The figure shows the effect on the non-dimensional power parameter P/</)ma,V-,) of variation in the dead-space ratio X, with constant values of r. k. and ir. The dead space is the porous volume nf the rcgcneraloi an<l other heal exchangers, connecting ducts, and the clearance volumes m the expansion and compression spaces. Increase in the dead volume decreases the ratio of maximum volume to minimum volume which decreases the range of the pressure exclusion, thus causinp a decrease in the cycle powei The dead space must he minimized for high cycle power.

design on die basis of parameter (PfpmM V,) results in a machine configuration of the maximum possible power within limits of the maximum pressure and combined swept volume. The maximum pressure of the working fluid is an important design criterion, since this affects the strength, and hence Ihe weighf, of the machine structure, whereas the combined swept-volume V, is indicative of the size of the structure. Clearly then, the power parameter P/(/)nm> VT) should be used for optimization purposes. However, once the basic machine configuration has been determined in terms of «■, k, t and X, the power parameter P,nB„ may he used thereafter. Both it and /'/(/>,„„, VT) are equally applicable, and will return the same numerical values for the engine power per cycle l\

By way of example. Fig. 5.14 is a comparison of the work diagram obtained for the optimum combination of phase angle o and swept-volume ratio k. with constant values of t and X. In all three cases, the pressures are adjusted to be fractions of Ihe maximum cycle-pressure, and cr> «.v. <v»mnjiriihlr. Similarly. in all three cases, the maximum value of the

Solar Stirling Engine Basics Explained

Solar Stirling Engine Basics Explained

The solar Stirling engine is progressively becoming a viable alternative to solar panels for its higher efficiency. Stirling engines might be the best way to harvest the power provided by the sun. This is an easy-to-understand explanation of how Stirling engines work, the different types, and why they are more efficient than steam engines.

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