Why would an engine be less efficient on Venus than on earth?

Answer 1

Efficiency of a space engine is the ratio of power to weight / and power to thrust ratio , used in duct propulsion by conversion of heat energy into exhaust velocity. Space engines are thermo acoustic engines that use bi propellant or solid fuel. Engines use different heat conversion methods in chemical or electrical power to ionize atoms and create voltage gradient to accelerate the ions to high exhaust velocity. The high temperature in the Venus atmosphere 7530Kelvin/4600 C is the main cause of inefficiency in space engine that can only use only heat exhaust for propulsion.

The other reasons for inefficiency of a heat propulsion engine is the dominant 96% CO2 + 4% Nitrogen with clouds of sulfuric acid in the atmosphere.

Answer 2

Venus has a smaller mass than Earth, and a slightly smaller diameter. The gravitational force of attraction between two masses depends on their masses and the distance between them.

The mass of Venus is 18.5% less than the mass of Earth. The radius of Venus is 5.5% smaller than the Earth's radius, meaning that if you stood on the surface of Venus, you would be 5.5% closer to the center of planetary mass than you are when you stand on Earth's surface.

The result of the smaller radius, but even smaller mass, is that on the surface of Venus, you would weigh 9.7% less than you weigh on the Earth's surface.

Answer 3

Presumably, you are thinking about heat engines. The higher environmental temperature on Venus would make it less efficient, assuming it runs at the same temperature as on Earth. Look at the Carnot equation, and plug in some numbers.

Answer 4

Earth has more gravity then Venus does because Earth is more dense than Venus.