Installation of Volvo Penta Diesel Engineby Generator D. Diesel Generator
Installation of Volvo Penta Diesel Engine
Volvo Penta only uses liquid-cooled engines. The cooling system comprises a cooling water system and a cooling air system. The objective of the system is to lead heat from the engine to the surrounding atmosphere. Around 40 % of fuel energy is used to perform mechanical work, while the rest is lost as heat to the coolant and through the exhaust. The heat that is transferred to the coolant is 20-30 % of the fuel energy, and it must be carried away by the cooling system. The water pump forces coolant through the engine cooling ducts. Hot coolant enters the radiator, passes through pipes and is cooled by cooling air from the fan. In order to increase power and reduce exhaust emissions, a charge air cooler may be used. Volvo Penta uses two different types of charge air cooler. TWD engines have a water-to-air charge air cooler in which hot charge air is cooled by engine coolant. TAD engines use air-to-air charge air coolers in which charge air is cooled by cooling air from the fan. This type of charge air cooler is installed separately behind (or in front of) the regular radiator.
The cooling system must be dimensioned so that engine overheating is avoided during all ambient and operational conditions. It is therefore important to know the maximum air temperature and the environmental conditions where the engine will be used. Cooling requirements differ from engine to engine, and heat transfer to coolant is specified in the Sales
Support Tool, Partner Network for each engine. Additional to the heat transferred to the coolant from the engine, heat transfer from extra equipment, e.g. via the torque converter oil cooler, must also be taken into account when a cooling system is dimensioned. Cooling is also affected by obstacles to airflow and temperature increases above air-cooled accessories such as air conditioning condensers or air-cooled oil coolers. Air can also be heated by the engine and generator (generator set) before it passes through the radiator. In order for cooling to be as efficient as possible, it is important to minimize cooling air obstacles and prevent air recirculation by designing cooling air ducts and grilles correctly. Regarding the smaller VE series engines for which Volvo Penta does not provide a complete cooling assembly, all relevant data for the design of a correct cooling system is available under “Cooling system” and “Charge air cooling system” in the Sales Support Tool.
The function of the fan is to provide a cooling air flow. The fan creates a pressure increase that provides an air flow through the system components. Increased cooling air speed through the radiator core results in increased heat transfer from the fins to air. The air flow created by the fan depends largely on the pressure drop from components in the system. The fan is of axial flow type, but the air flow is not entirely axial. With an increase in installation pressure drop the air flow becomes more radial. The fan is usually belt driven, but on mobile applications certain engines also have crankshaft-mounted fans as an option. A crankshaft-mounted fan is exposed to higher stresses than a belt-driven fan. There are two main types of axial fans: fixed fans and temperature-controlled fans. The fan is an installation safety item and Volvo Penta fans are thoroughly tested before they are approved. Volvo Penta therefore recommends that only genuine Volvo Penta fans be used.
Created on Jun 2nd 2018 05:31. Viewed 249 times.