The following are reasons why we use assumptions to represent reciprocating engines as closed system cycles, EXCEPT: a.All statementds are valid b.Reciprocating engines have equivalent thermal efficiencies as their corresponding cycles c.The shape and behavior of reciprocating engines are too complex d.The working fluid for reciprocating engines is an air-fuel mixture, which could be difficult to model

The following are reasons why we use assumptions to represent reciprocating engines as closed system cycles, EXCEPT: a.All statementds are valid b.Reciprocating engines have equivalent thermal efficiencies as their corresponding cycles c.The shape and behavior of reciprocating engines are too complex d.The working fluid for reciprocating engines is an air-fuel mixture, which could be difficult to model

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

Calculate the net work per cycle, in kJ; B) the power developed by a motor, in kW and C) the thermal efficiency if the cycle is executed 1500 times in one minute. To answer the above, consider that the displacement volume of a Diesel internal combustion engine is 3 liters. The cutoff ratio is 2, and the conditions at the start of compression are set to 100 kPa, 22°C, and 3.17 liters.
Ts diagrams for two reversible thermodynamic power cycles are shown in the following figure. Both cycles operate between a high temperature reservoir at 500 K and a low temperature reservoir at 300 K. The process on the left is the Carnot cycle described in Section 2.9. The process on the right is a Stirling cycle, which is similar to a Carnot cycle, except that the two steps (state 4 to state 1) and (state 2 to state 3) are at constant volume. Which cycle, if either, has a greater efficiency? Explain.
(Thermodynamics) A steady-flow system operating on the ideal Ericsson cycle can achieve the Carnot efficiency. One of the salient features of this cycle is the isothermal expansion through a heated turbine, as shown in Fig. a. Heat is added to the turbine such that the outlet temperature is equal to the inlet temperature, i.e. T₁=T₂, and the overall pressure ratio for this process is rₚ=P₁/P₂. However, an isothermal expansion through a heated turbine is very difficult to achieve in practical engineering applications. An alternate approach is two use a multi-stage expansion process with reheating. In this approach, the gas expansion process is carried out in multiple stages with reheating in between each stage. Consider the two-stage turbine expansion with reheating shown in Fig. b. The gas enters the first stage of the turbine at state A1, is expanded isentropically to an intermediate pressure Pₐ₂, is reheated at constant pressure to state B1, and is expanded in the second stage…
Ts diagrams for two reversible thermodynamic power cycles are shown in the following fig- ure. Both cycles operate between a high temperature reservoir at 500 K and a low temperature reservoir at 300 K. The process on the left is the Carnot cycle described in Section 2.9. The process on the right is a Brayton cycle, which is similar to a Carnot cycle, except that the two steps (state 1 to state 2) and (state 3 to state 4) are at constant pressure. Which cycle, if either, has a greater efficiency? Explain.
The volume ratios of compression and expansion for a diesel engine as measured from an indicator diagram are 16 and 8 respectively. The pressure and temperature at the beginning of the compression are 1 bar and 28°C. Assuming an ideal engine, determine the mean effective pressure, the ratio of maximum pressure to mean effective pressure and cycle efficiency. Also find the fuel consumption per kWh if the indicated thermal efficiency is 0.5 of ideal efficiency, mechanical efficiency is 0.8 and the calorific value of oil 42000 kJ/kg. Assume for air : cp = 1.005 kJ/kg K ; cv = 0.718 kJ/kg K, ã = 1.4. Please also draw the PV diagram.
THERMODYNAMICS The compression ratio of 20:1 of a diesel engine with an input pressure of 95 kPa, 290 K, state 1, and a volume of 0.5 L. The maximum cycle temperature is 1800 K Determine the maximum pressure, the net-work, the cutoff ratio, and the thermal efficiency. (By varying specific heat). Show Complete Solution on a Paper.
Thermodynamics The actual cycle of a 5T diesel engine, with a displacement of 7000 cm³ , 2,400 rpm is approximate to the theoretical cycle represented in the figure below, in which the custom rectangle has the area of the same cycle. A compression ratio is 17 and the thermal efficiency is 0.597 when 26.3% of the heat is provided isochorically. It is adopted that the active liquid has ϒ = 1.35 and R = 240J / KgK. To determine a) The values of p T and v at the main points of the cycle; b) The power of the cycle. c) Expansion work.
PART B ONLY A gas-turbine power generator operates on an ideal air-standard Brayton cycle 1 → 2 → 3 → 4 shown in Fig. 1. The gas temperatures at the compressor inlet, compressor exit, and turbine inlet are T1 = 300 K, T2 = 600 K, and T3 = 1200 K, respectively. Solve the problem below using the variable specific heat assumption. PART B - Determine the pressure ratio rp = P2/P1 and the temperature at the turbine exit, T4 (in K).
Essay Topic: Define the following terms related to reciprocating engines: cycle, stroke, bore, clearance volume, volume displacement, clearance percentage, compression ratio, cut-off ratio, pressure ratio, and thermal efficiency.
In an axial flow compressor of Boeing 777 Turbofan engine, air enters ambient conditions 17 C and 1 bar. The axial velocity of air is 180 m/s (constant throughout the stage), the rotor speed of 200 m/s, the absolute velocity at the inlet is 185 m/s, the work done factor is 0.95, and the degree of reaction is 50%. If the stage efficiency is 0.86, calculate the air angles at the rotor inlet and outlet, the static temperature at the inlet of the first stage, and stage pressure ratio. *
Write legibly, provide manual step by step solution, and diagram for below given problem. A superheat steam Rankine cycle has turbine inlet conditions of 17.5 Mpa and 530 C expands in a turbine to 0.007Mpa. The turbine and pumps polytropic efficiencies are 0.9 and 0.7 respectively, pressure losses between pump and turbine are 1.5MPa. What should be the pump work in KJ/kg? A. 17.3 C. 37.3 B. 27.3 D. 43.4
Sketch the P-V diagram of the Internal Combustion Engine showing the ideal cycles of a DieselEngine. Label the events.